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2021-06-24net: retrieve netns cookie via getsocketoptMartynas Pumputis1-0/+2
It's getting more common to run nested container environments for testing cloud software. One of such examples is Kind [1] which runs a Kubernetes cluster in Docker containers on a single host. Each container acts as a Kubernetes node, and thus can run any Pod (aka container) inside the former. This approach simplifies testing a lot, as it eliminates complicated VM setups. Unfortunately, such a setup breaks some functionality when cgroupv2 BPF programs are used for load-balancing. The load-balancer BPF program needs to detect whether a request originates from the host netns or a container netns in order to allow some access, e.g. to a service via a loopback IP address. Typically, the programs detect this by comparing netns cookies with the one of the init ns via a call to bpf_get_netns_cookie(NULL). However, in nested environments the latter cannot be used given the Kubernetes node's netns is outside the init ns. To fix this, we need to pass the Kubernetes node netns cookie to the program in a different way: by extending getsockopt() with a SO_NETNS_COOKIE option, the orchestrator which runs in the Kubernetes node netns can retrieve the cookie and pass it to the program instead. Thus, this is following up on Eric's commit 3d368ab87cf6 ("net: initialize net->net_cookie at netns setup") to allow retrieval via SO_NETNS_COOKIE. This is also in line in how we retrieve socket cookie via SO_COOKIE. [1] https://kind.sigs.k8s.io/ Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Martynas Pumputis <m@lambda.lt> Cc: Eric Dumazet <edumazet@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-15quota: finish disable quotactl_path syscallMarcin Juszkiewicz1-2/+1
In commit 5b9fedb31e47 ("quota: Disable quotactl_path syscall") Jan Kara disabled quotactl_path syscall on several architectures. This commit disables it on all architectures using unified list of system calls: - arm64 - arc - csky - h8300 - hexagon - nds32 - nios2 - openrisc - riscv (32/64) CC: Jan Kara <jack@suse.cz> CC: Christian Brauner <christian.brauner@ubuntu.com> CC: Sascha Hauer <s.hauer@pengutronix.de> Link: https://lore.kernel.org/lkml/20210512153621.n5u43jsytbik4yze@wittgenstein Link: https://lore.kernel.org/r/20210614153712.313707-1-marcin@juszkiewicz.com.pl Fixes: 5b9fedb31e47 ("quota: Disable quotactl_path syscall") Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Marcin Juszkiewicz <marcin@juszkiewicz.com.pl> Signed-off-by: Jan Kara <jack@suse.cz>
2021-05-21Merge branch 'for-v5.13-rc3' of ↵Linus Torvalds1-7/+8
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull siginfo fix from Eric Biederman: "During the merge window an issue with si_perf and the siginfo ABI came up. The alpha and sparc siginfo structure layout had changed with the addition of SIGTRAP TRAP_PERF and the new field si_perf. The reason only alpha and sparc were affected is that they are the only architectures that use si_trapno. Looking deeper it was discovered that si_trapno is used for only a few select signals on alpha and sparc, and that none of the other _sigfault fields past si_addr are used at all. Which means technically no regression on alpha and sparc. While the alignment concerns might be dismissed the abuse of si_errno by SIGTRAP TRAP_PERF does have the potential to cause regressions in existing userspace. While we still have time before userspace starts using and depending on the new definition siginfo for SIGTRAP TRAP_PERF this set of changes cleans up siginfo_t. - The si_trapno field is demoted from magic alpha and sparc status and made an ordinary union member of the _sigfault member of siginfo_t. Without moving it of course. - si_perf is replaced with si_perf_data and si_perf_type ending the abuse of si_errno. - Unnecessary additions to signalfd_siginfo are removed" * 'for-v5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: signalfd: Remove SIL_PERF_EVENT fields from signalfd_siginfo signal: Deliver all of the siginfo perf data in _perf signal: Factor force_sig_perf out of perf_sigtrap signal: Implement SIL_FAULT_TRAPNO siginfo: Move si_trapno inside the union inside _si_fault
2021-05-19signal: Deliver all of the siginfo perf data in _perfEric W. Biederman1-2/+6
Don't abuse si_errno and deliver all of the perf data in _perf member of siginfo_t. Note: The data field in the perf data structures in a u64 to allow a pointer to be encoded without needed to implement a 32bit and 64bit version of the same structure. There already exists a 32bit and 64bit versions siginfo_t, and the 32bit version can not include a 64bit member as it only has 32bit alignment. So unsigned long is used in siginfo_t instead of a u64 as unsigned long can encode a pointer on all architectures linux supports. v1: https://lkml.kernel.org/r/m11rarqqx2.fsf_-_@fess.ebiederm.org v2: https://lkml.kernel.org/r/20210503203814.25487-10-ebiederm@xmission.com v3: https://lkml.kernel.org/r/20210505141101.11519-11-ebiederm@xmission.com Link: https://lkml.kernel.org/r/20210517195748.8880-4-ebiederm@xmission.com Reviewed-by: Marco Elver <elver@google.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-05-19siginfo: Move si_trapno inside the union inside _si_faultEric W. Biederman1-5/+2
It turns out that linux uses si_trapno very sparingly, and as such it can be considered extra information for a very narrow selection of signals, rather than information that is present with every fault reported in siginfo. As such move si_trapno inside the union inside of _si_fault. This results in no change in placement, and makes it eaiser to extend _si_fault in the future as this reduces the number of special cases. In particular with si_trapno included in the union it is no longer a concern that the union must be pointer aligned on most architectures because the union follows immediately after si_addr which is a pointer. This change results in a difference in siginfo field placement on sparc and alpha for the fields si_addr_lsb, si_lower, si_upper, si_pkey, and si_perf. These architectures do not implement the signals that would use si_addr_lsb, si_lower, si_upper, si_pkey, and si_perf. Further these architecture have not yet implemented the userspace that would use si_perf. The point of this change is in fact to correct these placement issues before sparc or alpha grow userspace that cares. This change was discussed[1] and the agreement is that this change is currently safe. [1]: https://lkml.kernel.org/r/CAK8P3a0+uKYwL1NhY6Hvtieghba2hKYGD6hcKx5n8=4Gtt+pHA@mail.gmail.com Acked-by: Marco Elver <elver@google.com> v1: https://lkml.kernel.org/r/m1tunns7yf.fsf_-_@fess.ebiederm.org v2: https://lkml.kernel.org/r/20210505141101.11519-5-ebiederm@xmission.com Link: https://lkml.kernel.org/r/20210517195748.8880-1-ebiederm@xmission.com Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2021-05-02Merge tag 'landlock_v34' of ↵Linus Torvalds1-1/+8
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull Landlock LSM from James Morris: "Add Landlock, a new LSM from Mickaël Salaün. Briefly, Landlock provides for unprivileged application sandboxing. From Mickaël's cover letter: "The goal of Landlock is to enable to restrict ambient rights (e.g. global filesystem access) for a set of processes. Because Landlock is a stackable LSM [1], it makes possible to create safe security sandboxes as new security layers in addition to the existing system-wide access-controls. This kind of sandbox is expected to help mitigate the security impact of bugs or unexpected/malicious behaviors in user-space applications. Landlock empowers any process, including unprivileged ones, to securely restrict themselves. Landlock is inspired by seccomp-bpf but instead of filtering syscalls and their raw arguments, a Landlock rule can restrict the use of kernel objects like file hierarchies, according to the kernel semantic. Landlock also takes inspiration from other OS sandbox mechanisms: XNU Sandbox, FreeBSD Capsicum or OpenBSD Pledge/Unveil. In this current form, Landlock misses some access-control features. This enables to minimize this patch series and ease review. This series still addresses multiple use cases, especially with the combined use of seccomp-bpf: applications with built-in sandboxing, init systems, security sandbox tools and security-oriented APIs [2]" The cover letter and v34 posting is here: https://lore.kernel.org/linux-security-module/20210422154123.13086-1-mic@digikod.net/ See also: https://landlock.io/ This code has had extensive design discussion and review over several years" Link: https://lore.kernel.org/lkml/50db058a-7dde-441b-a7f9-f6837fe8b69f@schaufler-ca.com/ [1] Link: https://lore.kernel.org/lkml/f646e1c7-33cf-333f-070c-0a40ad0468cd@digikod.net/ [2] * tag 'landlock_v34' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: landlock: Enable user space to infer supported features landlock: Add user and kernel documentation samples/landlock: Add a sandbox manager example selftests/landlock: Add user space tests landlock: Add syscall implementations arch: Wire up Landlock syscalls fs,security: Add sb_delete hook landlock: Support filesystem access-control LSM: Infrastructure management of the superblock landlock: Add ptrace restrictions landlock: Set up the security framework and manage credentials landlock: Add ruleset and domain management landlock: Add object management
2021-04-29Merge tag 'for_v5.13-rc1' of ↵Linus Torvalds1-1/+3
git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs Pull quota, ext2, reiserfs updates from Jan Kara: - support for path (instead of device) based quotactl syscall (quotactl_path(2)) - ext2 conversion to kmap_local() - other minor cleanups & fixes * tag 'for_v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: fs/reiserfs/journal.c: delete useless variables fs/ext2: Replace kmap() with kmap_local_page() ext2: Match up ext2_put_page() with ext2_dotdot() and ext2_find_entry() fs/ext2/: fix misspellings using codespell tool quota: report warning limits for realtime space quotas quota: wire up quotactl_path quota: Add mountpath based quota support
2021-04-23signal, perf: Fix siginfo_t by avoiding u64 on 32-bit architecturesMarco Elver1-1/+1
The alignment of a structure is that of its largest member. On architectures like 32-bit Arm (but not e.g. 32-bit x86) 64-bit integers will require 64-bit alignment and not its natural word size. This means that there is no portable way to add 64-bit integers to siginfo_t on 32-bit architectures without breaking the ABI, because siginfo_t does not yet (and therefore likely never will) contain 64-bit fields on 32-bit architectures. Adding a 64-bit integer could change the alignment of the union after the 3 initial int si_signo, si_errno, si_code, thus introducing 4 bytes of padding shifting the entire union, which would break the ABI. One alternative would be to use the __packed attribute, however, it is non-standard C. Given siginfo_t has definitions outside the Linux kernel in various standard libraries that can be compiled with any number of different compilers (not just those we rely on), using non-standard attributes on siginfo_t should be avoided to ensure portability. In the case of the si_perf field, word size is sufficient since there is no exact requirement on size, given the data it contains is user-defined via perf_event_attr::sig_data. On 32-bit architectures, any excess bits of perf_event_attr::sig_data will therefore be truncated when copying into si_perf. Since si_perf is intended to disambiguate events (e.g. encoding relevant information if there are more events of the same type), 32 bits should provide enough entropy to do so on 32-bit architectures. For 64-bit architectures, no change is intended. Fixes: fb6cc127e0b6 ("signal: Introduce TRAP_PERF si_code and si_perf to siginfo") Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Reported-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Link: https://lkml.kernel.org/r/20210422191823.79012-1-elver@google.com
2021-04-22arch: Wire up Landlock syscallsMickaël Salaün1-1/+7
Wire up the following system calls for all architectures: * landlock_create_ruleset(2) * landlock_add_rule(2) * landlock_restrict_self(2) Cc: Arnd Bergmann <arnd@arndb.de> Cc: James Morris <jmorris@namei.org> Cc: Jann Horn <jannh@google.com> Cc: Kees Cook <keescook@chromium.org> Cc: Serge E. Hallyn <serge@hallyn.com> Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com> Link: https://lore.kernel.org/r/20210422154123.13086-10-mic@digikod.net Signed-off-by: James Morris <jamorris@linux.microsoft.com>
2021-04-16signal: Introduce TRAP_PERF si_code and si_perf to siginfoMarco Elver1-1/+5
Introduces the TRAP_PERF si_code, and associated siginfo_t field si_perf. These will be used by the perf event subsystem to send signals (if requested) to the task where an event occurred. Signed-off-by: Marco Elver <elver@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k Acked-by: Arnd Bergmann <arnd@arndb.de> # asm-generic Link: https://lkml.kernel.org/r/20210408103605.1676875-6-elver@google.com
2021-03-17quota: wire up quotactl_pathSascha Hauer1-1/+3
Wire up the quotactl_path syscall added in the previous patch. Link: https://lore.kernel.org/r/20210304123541.30749-3-s.hauer@pengutronix.de Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz>
2021-01-24fs: add mount_setattr()Christian Brauner1-1/+3
This implements the missing mount_setattr() syscall. While the new mount api allows to change the properties of a superblock there is currently no way to change the properties of a mount or a mount tree using file descriptors which the new mount api is based on. In addition the old mount api has the restriction that mount options cannot be applied recursively. This hasn't changed since changing mount options on a per-mount basis was implemented in [1] and has been a frequent request not just for convenience but also for security reasons. The legacy mount syscall is unable to accommodate this behavior without introducing a whole new set of flags because MS_REC | MS_REMOUNT | MS_BIND | MS_RDONLY | MS_NOEXEC | [...] only apply the mount option to the topmost mount. Changing MS_REC to apply to the whole mount tree would mean introducing a significant uapi change and would likely cause significant regressions. The new mount_setattr() syscall allows to recursively clear and set mount options in one shot. Multiple calls to change mount options requesting the same changes are idempotent: int mount_setattr(int dfd, const char *path, unsigned flags, struct mount_attr *uattr, size_t usize); Flags to modify path resolution behavior are specified in the @flags argument. Currently, AT_EMPTY_PATH, AT_RECURSIVE, AT_SYMLINK_NOFOLLOW, and AT_NO_AUTOMOUNT are supported. If useful, additional lookup flags to restrict path resolution as introduced with openat2() might be supported in the future. The mount_setattr() syscall can be expected to grow over time and is designed with extensibility in mind. It follows the extensible syscall pattern we have used with other syscalls such as openat2(), clone3(), sched_{set,get}attr(), and others. The set of mount options is passed in the uapi struct mount_attr which currently has the following layout: struct mount_attr { __u64 attr_set; __u64 attr_clr; __u64 propagation; __u64 userns_fd; }; The @attr_set and @attr_clr members are used to clear and set mount options. This way a user can e.g. request that a set of flags is to be raised such as turning mounts readonly by raising MOUNT_ATTR_RDONLY in @attr_set while at the same time requesting that another set of flags is to be lowered such as removing noexec from a mount tree by specifying MOUNT_ATTR_NOEXEC in @attr_clr. Note, since the MOUNT_ATTR_<atime> values are an enum starting from 0, not a bitmap, users wanting to transition to a different atime setting cannot simply specify the atime setting in @attr_set, but must also specify MOUNT_ATTR__ATIME in the @attr_clr field. So we ensure that MOUNT_ATTR__ATIME can't be partially set in @attr_clr and that @attr_set can't have any atime bits set if MOUNT_ATTR__ATIME isn't set in @attr_clr. The @propagation field lets callers specify the propagation type of a mount tree. Propagation is a single property that has four different settings and as such is not really a flag argument but an enum. Specifically, it would be unclear what setting and clearing propagation settings in combination would amount to. The legacy mount() syscall thus forbids the combination of multiple propagation settings too. The goal is to keep the semantics of mount propagation somewhat simple as they are overly complex as it is. The @userns_fd field lets user specify a user namespace whose idmapping becomes the idmapping of the mount. This is implemented and explained in detail in the next patch. [1]: commit 2e4b7fcd9260 ("[PATCH] r/o bind mounts: honor mount writer counts at remount") Link: https://lore.kernel.org/r/20210121131959.646623-35-christian.brauner@ubuntu.com Cc: David Howells <dhowells@redhat.com> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Cc: linux-api@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-12-19epoll: wire up syscall epoll_pwait2Willem de Bruijn1-1/+3
Split off from prev patch in the series that implements the syscall. Link: https://lkml.kernel.org/r/20201121144401.3727659-4-willemdebruijn.kernel@gmail.com Signed-off-by: Willem de Bruijn <willemb@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-16Merge tag 'asm-generic-cleanup-5.11' of ↵Linus Torvalds2-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic cleanups from Arnd Bergmann: "These are a couple of compiler warning fixes to make 'make W=2' less noisy, as well as some fixes to code comments in asm-generic" * tag 'asm-generic-cleanup-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: syscalls: Fix file comments for syscalls implemented in kernel/sys.c ctype.h: remove duplicate isdigit() helper qspinlock: use signed temporaries for cmpxchg asm-generic: fix ffs -Wshadow warning asm-generic: percpu: avoid Wshadow warning asm-generic/sembuf: Update architecture related information in comment
2020-12-16Merge tag 'net-next-5.11' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - support "prefer busy polling" NAPI operation mode, where we defer softirq for some time expecting applications to periodically busy poll - AF_XDP: improve efficiency by more batching and hindering the adjacency cache prefetcher - af_packet: make packet_fanout.arr size configurable up to 64K - tcp: optimize TCP zero copy receive in presence of partial or unaligned reads making zero copy a performance win for much smaller messages - XDP: add bulk APIs for returning / freeing frames - sched: support fragmenting IP packets as they come out of conntrack - net: allow virtual netdevs to forward UDP L4 and fraglist GSO skbs BPF: - BPF switch from crude rlimit-based to memcg-based memory accounting - BPF type format information for kernel modules and related tracing enhancements - BPF implement task local storage for BPF LSM - allow the FENTRY/FEXIT/RAW_TP tracing programs to use bpf_sk_storage Protocols: - mptcp: improve multiple xmit streams support, memory accounting and many smaller improvements - TLS: support CHACHA20-POLY1305 cipher - seg6: add support for SRv6 End.DT4/DT6 behavior - sctp: Implement RFC 6951: UDP Encapsulation of SCTP - ppp_generic: add ability to bridge channels directly - bridge: Connectivity Fault Management (CFM) support as is defined in IEEE 802.1Q section 12.14. Drivers: - mlx5: make use of the new auxiliary bus to organize the driver internals - mlx5: more accurate port TX timestamping support - mlxsw: - improve the efficiency of offloaded next hop updates by using the new nexthop object API - support blackhole nexthops - support IEEE 802.1ad (Q-in-Q) bridging - rtw88: major bluetooth co-existance improvements - iwlwifi: support new 6 GHz frequency band - ath11k: Fast Initial Link Setup (FILS) - mt7915: dual band concurrent (DBDC) support - net: ipa: add basic support for IPA v4.5 Refactor: - a few pieces of in_interrupt() cleanup work from Sebastian Andrzej Siewior - phy: add support for shared interrupts; get rid of multiple driver APIs and have the drivers write a full IRQ handler, slight growth of driver code should be compensated by the simpler API which also allows shared IRQs - add common code for handling netdev per-cpu counters - move TX packet re-allocation from Ethernet switch tag drivers to a central place - improve efficiency and rename nla_strlcpy - number of W=1 warning cleanups as we now catch those in a patchwork build bot Old code removal: - wan: delete the DLCI / SDLA drivers - wimax: move to staging - wifi: remove old WDS wifi bridging support" * tag 'net-next-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1922 commits) net: hns3: fix expression that is currently always true net: fix proc_fs init handling in af_packet and tls nfc: pn533: convert comma to semicolon af_vsock: Assign the vsock transport considering the vsock address flags af_vsock: Set VMADDR_FLAG_TO_HOST flag on the receive path vsock_addr: Check for supported flag values vm_sockets: Add VMADDR_FLAG_TO_HOST vsock flag vm_sockets: Add flags field in the vsock address data structure net: Disable NETIF_F_HW_TLS_TX when HW_CSUM is disabled tcp: Add logic to check for SYN w/ data in tcp_simple_retransmit net: mscc: ocelot: install MAC addresses in .ndo_set_rx_mode from process context nfc: s3fwrn5: Release the nfc firmware net: vxget: clean up sparse warnings mlxsw: spectrum_router: Use eXtended mezzanine to offload IPv4 router mlxsw: spectrum: Set KVH XLT cache mode for Spectrum2/3 mlxsw: spectrum_router_xm: Introduce basic XM cache flushing mlxsw: reg: Add Router LPM Cache Enable Register mlxsw: reg: Add Router LPM Cache ML Delete Register mlxsw: spectrum_router_xm: Implement L-value tracking for M-index mlxsw: reg: Add XM Router M Table Register ...
2020-12-15Merge tag 'core-entry-2020-12-14' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core entry/exit updates from Thomas Gleixner: "A set of updates for entry/exit handling: - More generalization of entry/exit functionality - The consolidation work to reclaim TIF flags on x86 and also for non-x86 specific TIF flags which are solely relevant for syscall related work and have been moved into their own storage space. The x86 specific part had to be merged in to avoid a major conflict. - The TIF_NOTIFY_SIGNAL work which replaces the inefficient signal delivery mode of task work and results in an impressive performance improvement for io_uring. The non-x86 consolidation of this is going to come seperate via Jens. - The selective syscall redirection facility which provides a clean and efficient way to support the non-Linux syscalls of WINE by catching them at syscall entry and redirecting them to the user space emulation. This can be utilized for other purposes as well and has been designed carefully to avoid overhead for the regular fastpath. This includes the core changes and the x86 support code. - Simplification of the context tracking entry/exit handling for the users of the generic entry code which guarantee the proper ordering and protection. - Preparatory changes to make the generic entry code accomodate S390 specific requirements which are mostly related to their syscall restart mechanism" * tag 'core-entry-2020-12-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) entry: Add syscall_exit_to_user_mode_work() entry: Add exit_to_user_mode() wrapper entry_Add_enter_from_user_mode_wrapper entry: Rename exit_to_user_mode() entry: Rename enter_from_user_mode() docs: Document Syscall User Dispatch selftests: Add benchmark for syscall user dispatch selftests: Add kselftest for syscall user dispatch entry: Support Syscall User Dispatch on common syscall entry kernel: Implement selective syscall userspace redirection signal: Expose SYS_USER_DISPATCH si_code type x86: vdso: Expose sigreturn address on vdso to the kernel MAINTAINERS: Add entry for common entry code entry: Fix boot for !CONFIG_GENERIC_ENTRY x86: Support HAVE_CONTEXT_TRACKING_OFFSTACK context_tracking: Only define schedule_user() on !HAVE_CONTEXT_TRACKING_OFFSTACK archs sched: Detect call to schedule from critical entry code context_tracking: Don't implement exception_enter/exit() on CONFIG_HAVE_CONTEXT_TRACKING_OFFSTACK context_tracking: Introduce HAVE_CONTEXT_TRACKING_OFFSTACK x86: Reclaim unused x86 TI flags ...
2020-12-02signal: Expose SYS_USER_DISPATCH si_code typeGabriel Krisman Bertazi1-1/+2
SYS_USER_DISPATCH will be triggered when a syscall is sent to userspace by the Syscall User Dispatch mechanism. This adjusts eventual BUILD_BUG_ON around the tree. Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Andy Lutomirski <luto@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20201127193238.821364-3-krisman@collabora.com
2020-12-01net: Add SO_BUSY_POLL_BUDGET socket optionBjörn Töpel1-0/+1
This option lets a user set a per socket NAPI budget for busy-polling. If the options is not set, it will use the default of 8. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/bpf/20201130185205.196029-3-bjorn.topel@gmail.com
2020-12-01net: Introduce preferred busy-pollingBjörn Töpel1-0/+2
The existing busy-polling mode, enabled by the SO_BUSY_POLL socket option or system-wide using the /proc/sys/net/core/busy_read knob, is an opportunistic. That means that if the NAPI context is not scheduled, it will poll it. If, after busy-polling, the budget is exceeded the busy-polling logic will schedule the NAPI onto the regular softirq handling. One implication of the behavior above is that a busy/heavy loaded NAPI context will never enter/allow for busy-polling. Some applications prefer that most NAPI processing would be done by busy-polling. This series adds a new socket option, SO_PREFER_BUSY_POLL, that works in concert with the napi_defer_hard_irqs and gro_flush_timeout knobs. The napi_defer_hard_irqs and gro_flush_timeout knobs were introduced in commit 6f8b12d661d0 ("net: napi: add hard irqs deferral feature"), and allows for a user to defer interrupts to be enabled and instead schedule the NAPI context from a watchdog timer. When a user enables the SO_PREFER_BUSY_POLL, again with the other knobs enabled, and the NAPI context is being processed by a softirq, the softirq NAPI processing will exit early to allow the busy-polling to be performed. If the application stops performing busy-polling via a system call, the watchdog timer defined by gro_flush_timeout will timeout, and regular softirq handling will resume. In summary; Heavy traffic applications that prefer busy-polling over softirq processing should use this option. Example usage: $ echo 2 | sudo tee /sys/class/net/ens785f1/napi_defer_hard_irqs $ echo 200000 | sudo tee /sys/class/net/ens785f1/gro_flush_timeout Note that the timeout should be larger than the userspace processing window, otherwise the watchdog will timeout and fall back to regular softirq processing. Enable the SO_BUSY_POLL/SO_PREFER_BUSY_POLL options on your socket. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/bpf/20201130185205.196029-2-bjorn.topel@gmail.com
2020-11-23signal: define the SA_EXPOSE_TAGBITS bit in sa_flagsPeter Collingbourne1-0/+3
Architectures that support address tagging, such as arm64, may want to expose fault address tag bits to the signal handler to help diagnose memory errors. However, these bits have not been previously set, and their presence may confuse unaware user applications. Therefore, introduce a SA_EXPOSE_TAGBITS flag bit in sa_flags that a signal handler may use to explicitly request that the bits are set. The generic signal handler APIs expect to receive tagged addresses. Architectures may specify how to untag addresses in the case where SA_EXPOSE_TAGBITS is clear by defining the arch_untagged_si_addr function. Signed-off-by: Peter Collingbourne <pcc@google.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Link: https://linux-review.googlesource.com/id/I16dd0ed2081f091fce97be0190cb8caa874c26cb Link: https://lkml.kernel.org/r/13cf24d00ebdd8e1f55caf1821c7c29d54100191.1605904350.git.pcc@google.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-11-23signal: define the SA_UNSUPPORTED bit in sa_flagsPeter Collingbourne1-0/+7
Define a sa_flags bit, SA_UNSUPPORTED, which will never be supported in the uapi. The purpose of this flag bit is to allow userspace to distinguish an old kernel that does not clear unknown sa_flags bits from a kernel that supports every flag bit. In other words, if userspace does something like: act.sa_flags |= SA_UNSUPPORTED; sigaction(SIGSEGV, &act, 0); sigaction(SIGSEGV, 0, &oldact); and finds that SA_UNSUPPORTED remains set in oldact.sa_flags, it means that the kernel cannot be trusted to have cleared unknown flag bits from sa_flags, so no assumptions about flag bit support can be made. Signed-off-by: Peter Collingbourne <pcc@google.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Link: https://linux-review.googlesource.com/id/Ic2501ad150a3a79c1cf27fb8c99be342e9dffbcb Link: https://lkml.kernel.org/r/bda7ddff8895a9bc4ffc5f3cf3d4d37a32118077.1605582887.git.pcc@google.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-11-23arch: provide better documentation for the arch-specific SA_* flagsPeter Collingbourne1-8/+14
Instead of documenting the arch-specific flag values in a comment at the top where they may be easily overlooked, document them in comments inline with the definitions in numerical order so that it is clear why specific values must be chosen for new generic flags and to reduce the likelihood of conflicts between generic and arch-specific flags. Signed-off-by: Peter Collingbourne <pcc@google.com> Link: https://linux-review.googlesource.com/id/I40a129cf7c3a71ba1bfd6d936c544072ee3b7ce6 Link: https://lkml.kernel.org/r/198c8b68c76bf3ed73117d817c7cdf9bc0eb174f.1605582887.git.pcc@google.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-11-23arch: move SA_* definitions to generic headersPeter Collingbourne2-29/+47
Most architectures with the exception of alpha, mips, parisc and sparc use the same values for these flags. Move their definitions into asm-generic/signal-defs.h and allow the architectures with non-standard values to override them. Also, document the non-standard flag values in order to make it easier to add new generic flags in the future. A consequence of this change is that on powerpc and x86, the constants' values aside from SA_RESETHAND change signedness from unsigned to signed. This is not expected to impact realistic use of these constants. In particular the typical use of the constants where they are or'ed together and assigned to sa_flags (or another int variable) would not be affected. Signed-off-by: Peter Collingbourne <pcc@google.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Reviewed-by: Dave Martin <Dave.Martin@arm.com> Link: https://linux-review.googlesource.com/id/Ia3849f18b8009bf41faca374e701cdca36974528 Link: https://lkml.kernel.org/r/b6d0d1ec34f9ee93e1105f14f288fba5f89d1f24.1605235762.git.pcc@google.com Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-11-13syscalls: Fix file comments for syscalls implemented in kernel/sys.cTal Zussman1-1/+1
The relevant syscalls were previously moved from kernel/timer.c to kernel/sys.c, but the comments weren't updated to reflect this change. Fixing these comments messes up the alphabetical ordering of syscalls by filename. This could be fixed by merging the two groups of kernel/sys.c syscalls, but that would require reordering the syscalls and renumbering them to maintain the numerical order in unistd.h. Signed-off-by: Tal Zussman <tz2294@columbia.edu> Link: https://lore.kernel.org/r/20201112215657.GA4539@charmander' Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-10-26asm-generic/sembuf: Update architecture related information in commentViresh Kumar1-3/+3
The structure came originally from x86_32 but is used by most of the architectures now. Update the comment which says it is for x86 only. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/64efe033394b6f0dfef043a63fd8897a81ba6d16.1589970173.git.viresh.kumar@linaro.org'
2020-10-18mm/madvise: introduce process_madvise() syscall: an external memory hinting APIMinchan Kim1-1/+3
There is usecase that System Management Software(SMS) want to give a memory hint like MADV_[COLD|PAGEEOUT] to other processes and in the case of Android, it is the ActivityManagerService. The information required to make the reclaim decision is not known to the app. Instead, it is known to the centralized userspace daemon(ActivityManagerService), and that daemon must be able to initiate reclaim on its own without any app involvement. To solve the issue, this patch introduces a new syscall process_madvise(2). It uses pidfd of an external process to give the hint. It also supports vector address range because Android app has thousands of vmas due to zygote so it's totally waste of CPU and power if we should call the syscall one by one for each vma.(With testing 2000-vma syscall vs 1-vector syscall, it showed 15% performance improvement. I think it would be bigger in real practice because the testing ran very cache friendly environment). Another potential use case for the vector range is to amortize the cost ofTLB shootdowns for multiple ranges when using MADV_DONTNEED; this could benefit users like TCP receive zerocopy and malloc implementations. In future, we could find more usecases for other advises so let's make it happens as API since we introduce a new syscall at this moment. With that, existing madvise(2) user could replace it with process_madvise(2) with their own pid if they want to have batch address ranges support feature. ince it could affect other process's address range, only privileged process(PTRACE_MODE_ATTACH_FSCREDS) or something else(e.g., being the same UID) gives it the right to ptrace the process could use it successfully. The flag argument is reserved for future use if we need to extend the API. I think supporting all hints madvise has/will supported/support to process_madvise is rather risky. Because we are not sure all hints make sense from external process and implementation for the hint may rely on the caller being in the current context so it could be error-prone. Thus, I just limited hints as MADV_[COLD|PAGEOUT] in this patch. If someone want to add other hints, we could hear the usecase and review it for each hint. It's safer for maintenance rather than introducing a buggy syscall but hard to fix it later. So finally, the API is as follows, ssize_t process_madvise(int pidfd, const struct iovec *iovec, unsigned long vlen, int advice, unsigned int flags); DESCRIPTION The process_madvise() system call is used to give advice or directions to the kernel about the address ranges from external process as well as local process. It provides the advice to address ranges of process described by iovec and vlen. The goal of such advice is to improve system or application performance. The pidfd selects the process referred to by the PID file descriptor specified in pidfd. (See pidofd_open(2) for further information) The pointer iovec points to an array of iovec structures, defined in <sys/uio.h> as: struct iovec { void *iov_base; /* starting address */ size_t iov_len; /* number of bytes to be advised */ }; The iovec describes address ranges beginning at address(iov_base) and with size length of bytes(iov_len). The vlen represents the number of elements in iovec. The advice is indicated in the advice argument, which is one of the following at this moment if the target process specified by pidfd is external. MADV_COLD MADV_PAGEOUT Permission to provide a hint to external process is governed by a ptrace access mode PTRACE_MODE_ATTACH_FSCREDS check; see ptrace(2). The process_madvise supports every advice madvise(2) has if target process is in same thread group with calling process so user could use process_madvise(2) to extend existing madvise(2) to support vector address ranges. RETURN VALUE On success, process_madvise() returns the number of bytes advised. This return value may be less than the total number of requested bytes, if an error occurred. The caller should check return value to determine whether a partial advice occurred. FAQ: Q.1 - Why does any external entity have better knowledge? Quote from Sandeep "For Android, every application (including the special SystemServer) are forked from Zygote. The reason of course is to share as many libraries and classes between the two as possible to benefit from the preloading during boot. After applications start, (almost) all of the APIs end up calling into this SystemServer process over IPC (binder) and back to the application. In a fully running system, the SystemServer monitors every single process periodically to calculate their PSS / RSS and also decides which process is "important" to the user for interactivity. So, because of how these processes start _and_ the fact that the SystemServer is looping to monitor each process, it does tend to *know* which address range of the application is not used / useful. Besides, we can never rely on applications to clean things up themselves. We've had the "hey app1, the system is low on memory, please trim your memory usage down" notifications for a long time[1]. They rely on applications honoring the broadcasts and very few do. So, if we want to avoid the inevitable killing of the application and restarting it, some way to be able to tell the OS about unimportant memory in these applications will be useful. - ssp Q.2 - How to guarantee the race(i.e., object validation) between when giving a hint from an external process and get the hint from the target process? process_madvise operates on the target process's address space as it exists at the instant that process_madvise is called. If the space target process can run between the time the process_madvise process inspects the target process address space and the time that process_madvise is actually called, process_madvise may operate on memory regions that the calling process does not expect. It's the responsibility of the process calling process_madvise to close this race condition. For example, the calling process can suspend the target process with ptrace, SIGSTOP, or the freezer cgroup so that it doesn't have an opportunity to change its own address space before process_madvise is called. Another option is to operate on memory regions that the caller knows a priori will be unchanged in the target process. Yet another option is to accept the race for certain process_madvise calls after reasoning that mistargeting will do no harm. The suggested API itself does not provide synchronization. It also apply other APIs like move_pages, process_vm_write. The race isn't really a problem though. Why is it so wrong to require that callers do their own synchronization in some manner? Nobody objects to write(2) merely because it's possible for two processes to open the same file and clobber each other's writes --- instead, we tell people to use flock or something. Think about mmap. It never guarantees newly allocated address space is still valid when the user tries to access it because other threads could unmap the memory right before. That's where we need synchronization by using other API or design from userside. It shouldn't be part of API itself. If someone needs more fine-grained synchronization rather than process level, there were two ideas suggested - cookie[2] and anon-fd[3]. Both are applicable via using last reserved argument of the API but I don't think it's necessary right now since we have already ways to prevent the race so don't want to add additional complexity with more fine-grained optimization model. To make the API extend, it reserved an unsigned long as last argument so we could support it in future if someone really needs it. Q.3 - Why doesn't ptrace work? Injecting an madvise in the target process using ptrace would not work for us because such injected madvise would have to be executed by the target process, which means that process would have to be runnable and that creates the risk of the abovementioned race and hinting a wrong VMA. Furthermore, we want to act the hint in caller's context, not the callee's, because the callee is usually limited in cpuset/cgroups or even freezed state so they can't act by themselves quick enough, which causes more thrashing/kill. It doesn't work if the target process are ptraced(e.g., strace, debugger, minidump) because a process can have at most one ptracer. [1] https://developer.android.com/topic/performance/memory" [2] process_getinfo for getting the cookie which is updated whenever vma of process address layout are changed - Daniel Colascione - https://lore.kernel.org/lkml/20190520035254.57579-1-minchan@kernel.org/T/#m7694416fd179b2066a2c62b5b139b14e3894e224 [3] anonymous fd which is used for the object(i.e., address range) validation - Michal Hocko - https://lore.kernel.org/lkml/20200120112722.GY18451@dhcp22.suse.cz/ [minchan@kernel.org: fix process_madvise build break for arm64] Link: http://lkml.kernel.org/r/20200303145756.GA219683@google.com [minchan@kernel.org: fix build error for mips of process_madvise] Link: http://lkml.kernel.org/r/20200508052517.GA197378@google.com [akpm@linux-foundation.org: fix patch ordering issue] [akpm@linux-foundation.org: fix arm64 whoops] [minchan@kernel.org: make process_madvise() vlen arg have type size_t, per Florian] [akpm@linux-foundation.org: fix i386 build] [sfr@canb.auug.org.au: fix syscall numbering] Link: https://lkml.kernel.org/r/20200905142639.49fc3f1a@canb.auug.org.au [sfr@canb.auug.org.au: madvise.c needs compat.h] Link: https://lkml.kernel.org/r/20200908204547.285646b4@canb.auug.org.au [minchan@kernel.org: fix mips build] Link: https://lkml.kernel.org/r/20200909173655.GC2435453@google.com [yuehaibing@huawei.com: remove duplicate header which is included twice] Link: https://lkml.kernel.org/r/20200915121550.30584-1-yuehaibing@huawei.com [minchan@kernel.org: do not use helper functions for process_madvise] Link: https://lkml.kernel.org/r/20200921175539.GB387368@google.com [akpm@linux-foundation.org: pidfd_get_pid() gained an argument] [sfr@canb.auug.org.au: fix up for "iov_iter: transparently handle compat iovecs in import_iovec"] Link: https://lkml.kernel.org/r/20200928212542.468e1fef@canb.auug.org.au Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com> Cc: Brian Geffon <bgeffon@google.com> Cc: Christian Brauner <christian@brauner.io> Cc: Daniel Colascione <dancol@google.com> Cc: Jann Horn <jannh@google.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joel Fernandes <joel@joelfernandes.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Dias <joaodias@google.com> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oleksandr Natalenko <oleksandr@redhat.com> Cc: Sandeep Patil <sspatil@google.com> Cc: SeongJae Park <sj38.park@gmail.com> Cc: SeongJae Park <sjpark@amazon.de> Cc: Shakeel Butt <shakeelb@google.com> Cc: Sonny Rao <sonnyrao@google.com> Cc: Tim Murray <timmurray@google.com> Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Florian Weimer <fw@deneb.enyo.de> Cc: <linux-man@vger.kernel.org> Link: http://lkml.kernel.org/r/20200302193630.68771-3-minchan@kernel.org Link: http://lkml.kernel.org/r/20200508183320.GA125527@google.com Link: http://lkml.kernel.org/r/20200622192900.22757-4-minchan@kernel.org Link: https://lkml.kernel.org/r/20200901000633.1920247-4-minchan@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16Merge tag 'powerpc-5.10-1' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - A series from Nick adding ARCH_WANT_IRQS_OFF_ACTIVATE_MM & selecting it for powerpc, as well as a related fix for sparc. - Remove support for PowerPC 601. - Some fixes for watchpoints & addition of a new ptrace flag for detecting ISA v3.1 (Power10) watchpoint features. - A fix for kernels using 4K pages and the hash MMU on bare metal Power9 systems with > 16TB of RAM, or RAM on the 2nd node. - A basic idle driver for shallow stop states on Power10. - Tweaks to our sched domains code to better inform the scheduler about the hardware topology on Power9/10, where two SMT4 cores can be presented by firmware as an SMT8 core. - A series doing further reworks & cleanups of our EEH code. - Addition of a filter for RTAS (firmware) calls done via sys_rtas(), to prevent root from overwriting kernel memory. - Other smaller features, fixes & cleanups. Thanks to: Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Athira Rajeev, Biwen Li, Cameron Berkenpas, Cédric Le Goater, Christophe Leroy, Christoph Hellwig, Colin Ian King, Daniel Axtens, David Dai, Finn Thain, Frederic Barrat, Gautham R. Shenoy, Greg Kurz, Gustavo Romero, Ira Weiny, Jason Yan, Joel Stanley, Jordan Niethe, Kajol Jain, Konrad Rzeszutek Wilk, Laurent Dufour, Leonardo Bras, Liu Shixin, Luca Ceresoli, Madhavan Srinivasan, Mahesh Salgaonkar, Nathan Lynch, Nicholas Mc Guire, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Pedro Miraglia Franco de Carvalho, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Ravi Bangoria, Russell Currey, Satheesh Rajendran, Scott Cheloha, Segher Boessenkool, Srikar Dronamraju, Stan Johnson, Stephen Kitt, Stephen Rothwell, Thiago Jung Bauermann, Tyrel Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, Vasant Hegde, Wang Wensheng, Wolfram Sang, Yang Yingliang, zhengbin. * tag 'powerpc-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (228 commits) Revert "powerpc/pci: unmap legacy INTx interrupts when a PHB is removed" selftests/powerpc: Fix eeh-basic.sh exit codes cpufreq: powernv: Fix frame-size-overflow in powernv_cpufreq_reboot_notifier powerpc/time: Make get_tb() common to PPC32 and PPC64 powerpc/time: Make get_tbl() common to PPC32 and PPC64 powerpc/time: Remove get_tbu() powerpc/time: Avoid using get_tbl() and get_tbu() internally powerpc/time: Make mftb() common to PPC32 and PPC64 powerpc/time: Rename mftbl() to mftb() powerpc/32s: Remove #ifdef CONFIG_PPC_BOOK3S_32 in head_book3s_32.S powerpc/32s: Rename head_32.S to head_book3s_32.S powerpc/32s: Setup the early hash table at all time. powerpc/time: Remove ifdef in get_dec() and set_dec() powerpc: Remove get_tb_or_rtc() powerpc: Remove __USE_RTC() powerpc: Tidy up a bit after removal of PowerPC 601. powerpc: Remove support for PowerPC 601 powerpc: Remove PowerPC 601 powerpc: Drop SYNC_601() ISYNC_601() and SYNC() powerpc: Remove CONFIG_PPC601_SYNC_FIX ...
2020-10-13Merge branch 'compat.mount' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull compat mount cleanups from Al Viro: "The last remnants of mount(2) compat buried by Christoph. Buried into NFS, that is. Generally I'm less enthusiastic about "let's use in_compat_syscall() deep in call chain" kind of approach than Christoph seems to be, but in this case it's warranted - that had been an NFS-specific wart, hopefully not to be repeated in any other filesystems (read: any new filesystem introducing non-text mount options will get NAKed even if it doesn't mess the layout up). IOW, not worth trying to grow an infrastructure that would avoid that use of in_compat_syscall()..." * 'compat.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: remove compat_sys_mount fs,nfs: lift compat nfs4 mount data handling into the nfs code nfs: simplify nfs4_parse_monolithic
2020-10-13Merge branch 'work.iov_iter' of ↵Linus Torvalds1-7/+5
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull compat iovec cleanups from Al Viro: "Christoph's series around import_iovec() and compat variant thereof" * 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: security/keys: remove compat_keyctl_instantiate_key_iov mm: remove compat_process_vm_{readv,writev} fs: remove compat_sys_vmsplice fs: remove the compat readv/writev syscalls fs: remove various compat readv/writev helpers iov_iter: transparently handle compat iovecs in import_iovec iov_iter: refactor rw_copy_check_uvector and import_iovec iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c compat.h: fix a spelling error in <linux/compat.h>
2020-10-03mm: remove compat_process_vm_{readv,writev}Christoph Hellwig1-4/+2
Now that import_iovec handles compat iovecs, the native syscalls can be used for the compat case as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03fs: remove compat_sys_vmspliceChristoph Hellwig1-1/+1
Now that import_iovec handles compat iovecs, the native vmsplice syscall can be used for the compat case as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-10-03fs: remove the compat readv/writev syscallsChristoph Hellwig1-2/+2
Now that import_iovec handles compat iovecs, the native readv and writev syscalls can be used for the compat case as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-23fs: remove compat_sys_mountChristoph Hellwig1-1/+1
compat_sys_mount is identical to the regular sys_mount now, so remove it and use the native version everywhere. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-09-15powerpc/8xx: Support 16k hugepages with 4k pagesChristophe Leroy1-0/+1
The 8xx has 4 page sizes: 4k, 16k, 512k and 8M 4k and 16k can be selected at build time as standard page sizes, and 512k and 8M are hugepages. When 4k standard pages are selected, 16k pages are not available. Allow 16k pages as hugepages when 4k pages are used. To allow that, implement arch_make_huge_pte() which receives the necessary arguments to allow setting the PTE in accordance with the page size: - 512 k pages must have _PAGE_HUGE and _PAGE_SPS. They are set by pte_mkhuge(). arch_make_huge_pte() does nothing. - 16 k pages must have only _PAGE_SPS. arch_make_huge_pte() clears _PAGE_HUGE. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/a518abc29266a708dfbccc8fce9ae6694fe4c2c6.1598862623.git.christophe.leroy@csgroup.eu
2020-09-04arm64: mte: Add specific SIGSEGV codesVincenzo Frascino1-1/+3
Add MTE-specific SIGSEGV codes to siginfo.h and update the x86 BUILD_BUG_ON(NSIGSEGV != 7) compile check. Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com> [catalin.marinas@arm.com: renamed precise/imprecise to sync/async] [catalin.marinas@arm.com: dropped #ifdef __aarch64__, renumbered] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Will Deacon <will@kernel.org>
2020-08-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds1-2/+2
Pull networking updates from David Miller: 1) Support 6Ghz band in ath11k driver, from Rajkumar Manoharan. 2) Support UDP segmentation in code TSO code, from Eric Dumazet. 3) Allow flashing different flash images in cxgb4 driver, from Vishal Kulkarni. 4) Add drop frames counter and flow status to tc flower offloading, from Po Liu. 5) Support n-tuple filters in cxgb4, from Vishal Kulkarni. 6) Various new indirect call avoidance, from Eric Dumazet and Brian Vazquez. 7) Fix BPF verifier failures on 32-bit pointer arithmetic, from Yonghong Song. 8) Support querying and setting hardware address of a port function via devlink, use this in mlx5, from Parav Pandit. 9) Support hw ipsec offload on bonding slaves, from Jarod Wilson. 10) Switch qca8k driver over to phylink, from Jonathan McDowell. 11) In bpftool, show list of processes holding BPF FD references to maps, programs, links, and btf objects. From Andrii Nakryiko. 12) Several conversions over to generic power management, from Vaibhav Gupta. 13) Add support for SO_KEEPALIVE et al. to bpf_setsockopt(), from Dmitry Yakunin. 14) Various https url conversions, from Alexander A. Klimov. 15) Timestamping and PHC support for mscc PHY driver, from Antoine Tenart. 16) Support bpf iterating over tcp and udp sockets, from Yonghong Song. 17) Support 5GBASE-T i40e NICs, from Aleksandr Loktionov. 18) Add kTLS RX HW offload support to mlx5e, from Tariq Toukan. 19) Fix the ->ndo_start_xmit() return type to be netdev_tx_t in several drivers. From Luc Van Oostenryck. 20) XDP support for xen-netfront, from Denis Kirjanov. 21) Support receive buffer autotuning in MPTCP, from Florian Westphal. 22) Support EF100 chip in sfc driver, from Edward Cree. 23) Add XDP support to mvpp2 driver, from Matteo Croce. 24) Support MPTCP in sock_diag, from Paolo Abeni. 25) Commonize UDP tunnel offloading code by creating udp_tunnel_nic infrastructure, from Jakub Kicinski. 26) Several pci_ --> dma_ API conversions, from Christophe JAILLET. 27) Add FLOW_ACTION_POLICE support to mlxsw, from Ido Schimmel. 28) Add SK_LOOKUP bpf program type, from Jakub Sitnicki. 29) Refactor a lot of networking socket option handling code in order to avoid set_fs() calls, from Christoph Hellwig. 30) Add rfc4884 support to icmp code, from Willem de Bruijn. 31) Support TBF offload in dpaa2-eth driver, from Ioana Ciornei. 32) Support XDP_REDIRECT in qede driver, from Alexander Lobakin. 33) Support PCI relaxed ordering in mlx5 driver, from Aya Levin. 34) Support TCP syncookies in MPTCP, from Flowian Westphal. 35) Fix several tricky cases of PMTU handling wrt. briding, from Stefano Brivio. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2056 commits) net: thunderx: initialize VF's mailbox mutex before first usage usb: hso: remove bogus check for EINPROGRESS usb: hso: no complaint about kmalloc failure hso: fix bailout in error case of probe ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUM selftests/net: relax cpu affinity requirement in msg_zerocopy test mptcp: be careful on subflow creation selftests: rtnetlink: make kci_test_encap() return sub-test result selftests: rtnetlink: correct the final return value for the test net: dsa: sja1105: use detected device id instead of DT one on mismatch tipc: set ub->ifindex for local ipv6 address ipv6: add ipv6_dev_find() net: openvswitch: silence suspicious RCU usage warning Revert "vxlan: fix tos value before xmit" ptp: only allow phase values lower than 1 period farsync: switch from 'pci_' to 'dma_' API wan: wanxl: switch from 'pci_' to 'dma_' API hv_netvsc: do not use VF device if link is down dpaa2-eth: Fix passing zero to 'PTR_ERR' warning net: macb: Properly handle phylink on at91sam9x ...
2020-07-20net: remove compat_sys_{get,set}sockoptChristoph Hellwig1-2/+2
Now that the ->compat_{get,set}sockopt proto_ops methods are gone there is no good reason left to keep the compat syscalls separate. This fixes the odd use of unsigned int for the compat_setsockopt optlen and the missing sock_use_custom_sol_socket. It would also easily allow running the eBPF hooks for the compat syscalls, but such a large change in behavior does not belong into a consolidation patch like this one. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-17arch: wire-up close_range()Christian Brauner1-0/+2
This wires up the close_range() syscall into all arches at once. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: Jann Horn <jannh@google.com> Cc: David Howells <dhowells@redhat.com> Cc: Dmitry V. Levin <ldv@altlinux.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Florian Weimer <fweimer@redhat.com> Cc: linux-api@vger.kernel.org Cc: linux-alpha@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: linux-m68k@lists.linux-m68k.org Cc: linux-mips@vger.kernel.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Cc: x86@kernel.org
2020-05-14vfs: add faccessat2 syscallMiklos Szeredi1-1/+3
POSIX defines faccessat() as having a fourth "flags" argument, while the linux syscall doesn't have it. Glibc tries to emulate AT_EACCESS and AT_SYMLINK_NOFOLLOW, but AT_EACCESS emulation is broken. Add a new faccessat(2) syscall with the added flags argument and implement both flags. The value of AT_EACCESS is defined in glibc headers to be the same as AT_REMOVEDIR. Use this value for the kernel interface as well, together with the explanatory comment. Also add AT_EMPTY_PATH support, which is not documented by POSIX, but can be useful and is trivial to implement. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-02-21y2038: hide timeval/timespec/itimerval/itimerspec typesArnd Bergmann1-0/+2
There are no in-kernel users remaining, but there may still be users that include linux/time.h instead of sys/time.h from user space, so leave the types available to user space while hiding them from kernel space. Only the __kernel_old_* versions of these types remain now. Link: http://lkml.kernel.org/r/20200110154232.4104492-4-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-30Merge tag 'threads-v5.6' of ↵Linus Torvalds1-1/+3
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull thread management updates from Christian Brauner: "Sargun Dhillon over the last cycle has worked on the pidfd_getfd() syscall. This syscall allows for the retrieval of file descriptors of a process based on its pidfd. A task needs to have ptrace_may_access() permissions with PTRACE_MODE_ATTACH_REALCREDS (suggested by Oleg and Andy) on the target. One of the main use-cases is in combination with seccomp's user notification feature. As a reminder, seccomp's user notification feature was made available in v5.0. It allows a task to retrieve a file descriptor for its seccomp filter. The file descriptor is usually handed of to a more privileged supervising process. The supervisor can then listen for syscall events caught by the seccomp filter of the supervisee and perform actions in lieu of the supervisee, usually emulating syscalls. pidfd_getfd() is needed to expand its uses. There are currently two major users that wait on pidfd_getfd() and one future user: - Netflix, Sargun said, is working on a service mesh where users should be able to connect to a dns-based VIP. When a user connects to e.g. 1.2.3.4:80 that runs e.g. service "foo" they will be redirected to an envoy process. This service mesh uses seccomp user notifications and pidfd to intercept all connect calls and instead of connecting them to 1.2.3.4:80 connects them to e.g. 127.0.0.1:8080. - LXD uses the seccomp notifier heavily to intercept and emulate mknod() and mount() syscalls for unprivileged containers/processes. With pidfd_getfd() more uses-cases e.g. bridging socket connections will be possible. - The patchset has also seen some interest from the browser corner. Right now, Firefox is using a SECCOMP_RET_TRAP sandbox managed by a broker process. In the future glibc will start blocking all signals during dlopen() rendering this type of sandbox impossible. Hence, in the future Firefox will switch to a seccomp-user-nofication based sandbox which also makes use of file descriptor retrieval. The thread for this can be found at https://sourceware.org/ml/libc-alpha/2019-12/msg00079.html With pidfd_getfd() it is e.g. possible to bridge socket connections for the supervisee (binding to a privileged port) and taking actions on file descriptors on behalf of the supervisee in general. Sargun's first version was using an ioctl on pidfds but various people pushed for it to be a proper syscall which he duely implemented as well over various review cycles. Selftests are of course included. I've also added instructions how to deal with merge conflicts below. There's also a small fix coming from the kernel mentee project to correctly annotate struct sighand_struct with __rcu to fix various sparse warnings. We've received a few more such fixes and even though they are mostly trivial I've decided to postpone them until after -rc1 since they came in rather late and I don't want to risk introducing build warnings. Finally, there's a new prctl() command PR_{G,S}ET_IO_FLUSHER which is needed to avoid allocation recursions triggerable by storage drivers that have userspace parts that run in the IO path (e.g. dm-multipath, iscsi, etc). These allocation recursions deadlock the device. The new prctl() allows such privileged userspace components to avoid allocation recursions by setting the PF_MEMALLOC_NOIO and PF_LESS_THROTTLE flags. The patch carries the necessary acks from the relevant maintainers and is routed here as part of prctl() thread-management." * tag 'threads-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: prctl: PR_{G,S}ET_IO_FLUSHER to support controlling memory reclaim sched.h: Annotate sighand_struct with __rcu test: Add test for pidfd getfd arch: wire up pidfd_getfd syscall pid: Implement pidfd_getfd syscall vfs, fdtable: Add fget_task helper
2020-01-29Merge branch 'work.openat2' of ↵Linus Torvalds1-1/+4
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull openat2 support from Al Viro: "This is the openat2() series from Aleksa Sarai. I'm afraid that the rest of namei stuff will have to wait - it got zero review the last time I'd posted #work.namei, and there had been a leak in the posted series I'd caught only last weekend. I was going to repost it on Monday, but the window opened and the odds of getting any review during that... Oh, well. Anyway, openat2 part should be ready; that _did_ get sane amount of review and public testing, so here it comes" From Aleksa's description of the series: "For a very long time, extending openat(2) with new features has been incredibly frustrating. This stems from the fact that openat(2) is possibly the most famous counter-example to the mantra "don't silently accept garbage from userspace" -- it doesn't check whether unknown flags are present[1]. This means that (generally) the addition of new flags to openat(2) has been fraught with backwards-compatibility issues (O_TMPFILE has to be defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old kernels gave errors, since it's insecure to silently ignore the flag[2]). All new security-related flags therefore have a tough road to being added to openat(2). Furthermore, the need for some sort of control over VFS's path resolution (to avoid malicious paths resulting in inadvertent breakouts) has been a very long-standing desire of many userspace applications. This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset (which was a variant of David Drysdale's O_BENEATH patchset[4] which was a spin-off of the Capsicum project[5]) with a few additions and changes made based on the previous discussion within [6] as well as others I felt were useful. In line with the conclusions of the original discussion of AT_NO_JUMPS, the flag has been split up into separate flags. However, instead of being an openat(2) flag it is provided through a new syscall openat2(2) which provides several other improvements to the openat(2) interface (see the patch description for more details). The following new LOOKUP_* flags are added: LOOKUP_NO_XDEV: Blocks all mountpoint crossings (upwards, downwards, or through absolute links). Absolute pathnames alone in openat(2) do not trigger this. Magic-link traversal which implies a vfsmount jump is also blocked (though magic-link jumps on the same vfsmount are permitted). LOOKUP_NO_MAGICLINKS: Blocks resolution through /proc/$pid/fd-style links. This is done by blocking the usage of nd_jump_link() during resolution in a filesystem. The term "magic-links" is used to match with the only reference to these links in Documentation/, but I'm happy to change the name. It should be noted that this is different to the scope of ~LOOKUP_FOLLOW in that it applies to all path components. However, you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it will *not* fail (assuming that no parent component was a magic-link), and you will have an fd for the magic-link. In order to correctly detect magic-links, the introduction of a new LOOKUP_MAGICLINK_JUMPED state flag was required. LOOKUP_BENEATH: Disallows escapes to outside the starting dirfd's tree, using techniques such as ".." or absolute links. Absolute paths in openat(2) are also disallowed. Conceptually this flag is to ensure you "stay below" a certain point in the filesystem tree -- but this requires some additional to protect against various races that would allow escape using "..". Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it can trivially beam you around the filesystem (breaking the protection). In future, there might be similar safety checks done as in LOOKUP_IN_ROOT, but that requires more discussion. In addition, two new flags are added that expand on the above ideas: LOOKUP_NO_SYMLINKS: Does what it says on the tin. No symlink resolution is allowed at all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this can still be used with NOFOLLOW to open an fd for the symlink as long as no parent path had a symlink component. LOOKUP_IN_ROOT: This is an extension of LOOKUP_BENEATH that, rather than blocking attempts to move past the root, forces all such movements to be scoped to the starting point. This provides chroot(2)-like protection but without the cost of a chroot(2) for each filesystem operation, as well as being safe against race attacks that chroot(2) is not. If a race is detected (as with LOOKUP_BENEATH) then an error is generated, and similar to LOOKUP_BENEATH it is not permitted to cross magic-links with LOOKUP_IN_ROOT. The primary need for this is from container runtimes, which currently need to do symlink scoping in userspace[7] when opening paths in a potentially malicious container. There is a long list of CVEs that could have bene mitigated by having RESOLVE_THIS_ROOT (such as CVE-2017-1002101, CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a few). In order to make all of the above more usable, I'm working on libpathrs[8] which is a C-friendly library for safe path resolution. It features a userspace-emulated backend if the kernel doesn't support openat2(2). Hopefully we can get userspace to switch to using it, and thus get openat2(2) support for free once it's ready. Future work would include implementing things like RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow programs to be sure they don't hit DoSes though stale NFS handles)" * 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: Documentation: path-lookup: include new LOOKUP flags selftests: add openat2(2) selftests open: introduce openat2(2) syscall namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution namei: LOOKUP_IN_ROOT: chroot-like scoped resolution namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution namei: LOOKUP_NO_XDEV: block mountpoint crossing namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution namei: LOOKUP_NO_SYMLINKS: block symlink resolution namei: allow set_root() to produce errors namei: allow nd_jump_link() to produce errors nsfs: clean-up ns_get_path() signature to return int namei: only return -ECHILD from follow_dotdot_rcu()
2020-01-18open: introduce openat2(2) syscallAleksa Sarai1-1/+4
/* Background. */ For a very long time, extending openat(2) with new features has been incredibly frustrating. This stems from the fact that openat(2) is possibly the most famous counter-example to the mantra "don't silently accept garbage from userspace" -- it doesn't check whether unknown flags are present[1]. This means that (generally) the addition of new flags to openat(2) has been fraught with backwards-compatibility issues (O_TMPFILE has to be defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old kernels gave errors, since it's insecure to silently ignore the flag[2]). All new security-related flags therefore have a tough road to being added to openat(2). Userspace also has a hard time figuring out whether a particular flag is supported on a particular kernel. While it is now possible with contemporary kernels (thanks to [3]), older kernels will expose unknown flag bits through fcntl(F_GETFL). Giving a clear -EINVAL during openat(2) time matches modern syscall designs and is far more fool-proof. In addition, the newly-added path resolution restriction LOOKUP flags (which we would like to expose to user-space) don't feel related to the pre-existing O_* flag set -- they affect all components of path lookup. We'd therefore like to add a new flag argument. Adding a new syscall allows us to finally fix the flag-ignoring problem, and we can make it extensible enough so that we will hopefully never need an openat3(2). /* Syscall Prototype. */ /* * open_how is an extensible structure (similar in interface to * clone3(2) or sched_setattr(2)). The size parameter must be set to * sizeof(struct open_how), to allow for future extensions. All future * extensions will be appended to open_how, with their zero value * acting as a no-op default. */ struct open_how { /* ... */ }; int openat2(int dfd, const char *pathname, struct open_how *how, size_t size); /* Description. */ The initial version of 'struct open_how' contains the following fields: flags Used to specify openat(2)-style flags. However, any unknown flag bits or otherwise incorrect flag combinations (like O_PATH|O_RDWR) will result in -EINVAL. In addition, this field is 64-bits wide to allow for more O_ flags than currently permitted with openat(2). mode The file mode for O_CREAT or O_TMPFILE. Must be set to zero if flags does not contain O_CREAT or O_TMPFILE. resolve Restrict path resolution (in contrast to O_* flags they affect all path components). The current set of flags are as follows (at the moment, all of the RESOLVE_ flags are implemented as just passing the corresponding LOOKUP_ flag). RESOLVE_NO_XDEV => LOOKUP_NO_XDEV RESOLVE_NO_SYMLINKS => LOOKUP_NO_SYMLINKS RESOLVE_NO_MAGICLINKS => LOOKUP_NO_MAGICLINKS RESOLVE_BENEATH => LOOKUP_BENEATH RESOLVE_IN_ROOT => LOOKUP_IN_ROOT open_how does not contain an embedded size field, because it is of little benefit (userspace can figure out the kernel open_how size at runtime fairly easily without it). It also only contains u64s (even though ->mode arguably should be a u16) to avoid having padding fields which are never used in the future. Note that as a result of the new how->flags handling, O_PATH|O_TMPFILE is no longer permitted for openat(2). As far as I can tell, this has always been a bug and appears to not be used by userspace (and I've not seen any problems on my machines by disallowing it). If it turns out this breaks something, we can special-case it and only permit it for openat(2) but not openat2(2). After input from Florian Weimer, the new open_how and flag definitions are inside a separate header from uapi/linux/fcntl.h, to avoid problems that glibc has with importing that header. /* Testing. */ In a follow-up patch there are over 200 selftests which ensure that this syscall has the correct semantics and will correctly handle several attack scenarios. In addition, I've written a userspace library[4] which provides convenient wrappers around openat2(RESOLVE_IN_ROOT) (this is necessary because no other syscalls support RESOLVE_IN_ROOT, and thus lots of care must be taken when using RESOLVE_IN_ROOT'd file descriptors with other syscalls). During the development of this patch, I've run numerous verification tests using libpathrs (showing that the API is reasonably usable by userspace). /* Future Work. */ Additional RESOLVE_ flags have been suggested during the review period. These can be easily implemented separately (such as blocking auto-mount during resolution). Furthermore, there are some other proposed changes to the openat(2) interface (the most obvious example is magic-link hardening[5]) which would be a good opportunity to add a way for userspace to restrict how O_PATH file descriptors can be re-opened. Another possible avenue of future work would be some kind of CHECK_FIELDS[6] flag which causes the kernel to indicate to userspace which openat2(2) flags and fields are supported by the current kernel (to avoid userspace having to go through several guesses to figure it out). [1]: https://lwn.net/Articles/588444/ [2]: https://lore.kernel.org/lkml/CA+55aFyyxJL1LyXZeBsf2ypriraj5ut1XkNDsunRBqgVjZU_6Q@mail.gmail.com [3]: commit 629e014bb834 ("fs: completely ignore unknown open flags") [4]: https://sourceware.org/bugzilla/show_bug.cgi?id=17523 [5]: https://lore.kernel.org/lkml/20190930183316.10190-2-cyphar@cyphar.com/ [6]: https://youtu.be/ggD-eb3yPVs Suggested-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-01-17mm: Reserve asm-generic prot flags 0x10 and 0x20 for arch useDave Martin1-0/+2
The asm-generic/mman.h definitions are used by a few architectures that also define arch-specific PROT flags with value 0x10 and 0x20. This currently applies to sparc and powerpc for 0x10, while arm64 will soon join with 0x10 and 0x20. To help future maintainers, document the use of this flag in the asm-generic header too. Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Dave Martin <Dave.Martin@arm.com> [catalin.marinas@arm.com: reserve 0x20 as well] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2020-01-13arch: wire up pidfd_getfd syscallSargun Dhillon1-1/+3
This wires up the pidfd_getfd syscall for all architectures. Signed-off-by: Sargun Dhillon <sargun@sargun.me> Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20200107175927.4558-4-sargun@sargun.me Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2019-12-05arch: sembuf.h: make uapi asm/sembuf.h self-containedMasahiro Yamada1-0/+1
Userspace cannot compile <asm/sembuf.h> due to some missing type definitions. For example, building it for x86 fails as follows: CC usr/include/asm/sembuf.h.s In file included from <command-line>:32:0: usr/include/asm/sembuf.h:17:20: error: field `sem_perm' has incomplete type struct ipc64_perm sem_perm; /* permissions .. see ipc.h */ ^~~~~~~~ usr/include/asm/sembuf.h:24:2: error: unknown type name `__kernel_time_t' __kernel_time_t sem_otime; /* last semop time */ ^~~~~~~~~~~~~~~ usr/include/asm/sembuf.h:25:2: error: unknown type name `__kernel_ulong_t' __kernel_ulong_t __unused1; ^~~~~~~~~~~~~~~~ usr/include/asm/sembuf.h:26:2: error: unknown type name `__kernel_time_t' __kernel_time_t sem_ctime; /* last change time */ ^~~~~~~~~~~~~~~ usr/include/asm/sembuf.h:27:2: error: unknown type name `__kernel_ulong_t' __kernel_ulong_t __unused2; ^~~~~~~~~~~~~~~~ usr/include/asm/sembuf.h:29:2: error: unknown type name `__kernel_ulong_t' __kernel_ulong_t sem_nsems; /* no. of semaphores in array */ ^~~~~~~~~~~~~~~~ usr/include/asm/sembuf.h:30:2: error: unknown type name `__kernel_ulong_t' __kernel_ulong_t __unused3; ^~~~~~~~~~~~~~~~ usr/include/asm/sembuf.h:31:2: error: unknown type name `__kernel_ulong_t' __kernel_ulong_t __unused4; ^~~~~~~~~~~~~~~~ It is just a matter of missing include directive. Include <asm/ipcbuf.h> to make it self-contained, and add it to the compile-test coverage. Link: http://lkml.kernel.org/r/20191030063855.9989-3-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-05arch: msgbuf.h: make uapi asm/msgbuf.h self-containedMasahiro Yamada1-0/+2
Userspace cannot compile <asm/msgbuf.h> due to some missing type definitions. For example, building it for x86 fails as follows: CC usr/include/asm/msgbuf.h.s In file included from usr/include/asm/msgbuf.h:6:0, from <command-line>:32: usr/include/asm-generic/msgbuf.h:25:20: error: field `msg_perm' has incomplete type struct ipc64_perm msg_perm; ^~~~~~~~ usr/include/asm-generic/msgbuf.h:27:2: error: unknown type name `__kernel_time_t' __kernel_time_t msg_stime; /* last msgsnd time */ ^~~~~~~~~~~~~~~ usr/include/asm-generic/msgbuf.h:28:2: error: unknown type name `__kernel_time_t' __kernel_time_t msg_rtime; /* last msgrcv time */ ^~~~~~~~~~~~~~~ usr/include/asm-generic/msgbuf.h:29:2: error: unknown type name `__kernel_time_t' __kernel_time_t msg_ctime; /* last change time */ ^~~~~~~~~~~~~~~ usr/include/asm-generic/msgbuf.h:41:2: error: unknown type name `__kernel_pid_t' __kernel_pid_t msg_lspid; /* pid of last msgsnd */ ^~~~~~~~~~~~~~ usr/include/asm-generic/msgbuf.h:42:2: error: unknown type name `__kernel_pid_t' __kernel_pid_t msg_lrpid; /* last receive pid */ ^~~~~~~~~~~~~~ It is just a matter of missing include directive. Include <asm/ipcbuf.h> to make it self-contained, and add it to the compile-test coverage. Link: http://lkml.kernel.org/r/20191030063855.9989-2-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-05arch: ipcbuf.h: make uapi asm/ipcbuf.h self-containedMasahiro Yamada1-0/+2
Userspace cannot compile <asm/ipcbuf.h> due to some missing type definitions. For example, building it for x86 fails as follows: CC usr/include/asm/ipcbuf.h.s In file included from usr/include/asm/ipcbuf.h:1:0, from <command-line>:32: usr/include/asm-generic/ipcbuf.h:21:2: error: unknown type name `__kernel_key_t' __kernel_key_t key; ^~~~~~~~~~~~~~ usr/include/asm-generic/ipcbuf.h:22:2: error: unknown type name `__kernel_uid32_t' __kernel_uid32_t uid; ^~~~~~~~~~~~~~~~ usr/include/asm-generic/ipcbuf.h:23:2: error: unknown type name `__kernel_gid32_t' __kernel_gid32_t gid; ^~~~~~~~~~~~~~~~ usr/include/asm-generic/ipcbuf.h:24:2: error: unknown type name `__kernel_uid32_t' __kernel_uid32_t cuid; ^~~~~~~~~~~~~~~~ usr/include/asm-generic/ipcbuf.h:25:2: error: unknown type name `__kernel_gid32_t' __kernel_gid32_t cgid; ^~~~~~~~~~~~~~~~ usr/include/asm-generic/ipcbuf.h:26:2: error: unknown type name `__kernel_mode_t' __kernel_mode_t mode; ^~~~~~~~~~~~~~~ usr/include/asm-generic/ipcbuf.h:28:35: error: `__kernel_mode_t' undeclared here (not in a function) unsigned char __pad1[4 - sizeof(__kernel_mode_t)]; ^~~~~~~~~~~~~~~ usr/include/asm-generic/ipcbuf.h:31:2: error: unknown type name `__kernel_ulong_t' __kernel_ulong_t __unused1; ^~~~~~~~~~~~~~~~ usr/include/asm-generic/ipcbuf.h:32:2: error: unknown type name `__kernel_ulong_t' __kernel_ulong_t __unused2; ^~~~~~~~~~~~~~~~ It is just a matter of missing include directive. Include <linux/posix_types.h> to make it self-contained, and add it to the compile-test coverage. Link: http://lkml.kernel.org/r/20191030063855.9989-1-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-11-15y2038: ipc: remove __kernel_time_t reference from headersArnd Bergmann3-16/+15
There are two structures based on time_t that conflict between libc and kernel: timeval and timespec. Both are now renamed to __kernel_old_timeval and __kernel_old_timespec. For time_t, the old typedef is still __kernel_time_t. There is nothing wrong with that name, but it would be nice to not use that going forward as this type is used almost only in deprecated interfaces because of the y2038 overflow. In the IPC headers (msgbuf.h, sembuf.h, shmbuf.h), __kernel_time_t is only used for the 64-bit variants, which are not deprecated. Change these to a plain 'long', which is the same type as __kernel_time_t on all 64-bit architectures anyway, to reduce the number of users of the old type. Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-11-15y2038: add __kernel_old_timespec and __kernel_old_time_tArnd Bergmann1-0/+1
The 'struct timespec' definition can no longer be part of the uapi headers because it conflicts with a a now incompatible libc definition. Also, we really want to remove it in order to prevent new uses from creeping in. The same namespace conflict exists with time_t, which should also be removed. __kernel_time_t could be used safely, but adding 'old' in the name makes it clearer that this should not be used for new interfaces. Add a replacement __kernel_old_timespec structure and __kernel_old_time_t along the lines of __kernel_old_timeval. Acked-by: Deepa Dinamani <deepa.kernel@gmail.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>