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2022-07-08LoadPin: Enable loading from trusted dm-verity devicesMatthias Kaehlcke2-1/+182
Extend LoadPin to allow loading of kernel files from trusted dm-verity [1] devices. This change adds the concept of trusted verity devices to LoadPin. LoadPin maintains a list of root digests of verity devices it considers trusted. Userspace can populate this list through an ioctl on the new LoadPin securityfs entry 'dm-verity'. The ioctl receives a file descriptor of a file with verity digests as parameter. Verity reads the digests from this file after confirming that the file is located on the pinned root. The digest file must contain one digest per line. The list of trusted digests can only be set up once, which is typically done at boot time. When a kernel file is read LoadPin first checks (as usual) whether the file is located on the pinned root, if so the file can be loaded. Otherwise, if the verity extension is enabled, LoadPin determines whether the file is located on a verity backed device and whether the root digest of that device is in the list of trusted digests. The file can be loaded if the verity device has a trusted root digest. Background: As of now LoadPin restricts loading of kernel files to a single pinned filesystem, typically the rootfs. This works for many systems, however it can result in a bloated rootfs (and OTA updates) on platforms where multiple boards with different hardware configurations use the same rootfs image. Especially when 'optional' files are large it may be preferable to download/install them only when they are actually needed by a given board. Chrome OS uses Downloadable Content (DLC) [2] to deploy certain 'packages' at runtime. As an example a DLC package could contain firmware for a peripheral that is not present on all boards. DLCs use dm-verity to verify the integrity of the DLC content. [1] https://www.kernel.org/doc/html/latest/admin-guide/device-mapper/verity.html [2] https://chromium.googlesource.com/chromiumos/platform2/+/HEAD/dlcservice/docs/developer.md Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Acked-by: Mike Snitzer <snitzer@kernel.org> Link: https://lore.kernel.org/lkml/20220627083512.v7.2.I01c67af41d2f6525c6d023101671d7339a9bc8b5@changeid Signed-off-by: Kees Cook <keescook@chromium.org>
2022-07-07ima: Fix a potential integer overflow in ima_appraise_measurementHuaxin Lu1-1/+2
When the ima-modsig is enabled, the rc passed to evm_verifyxattr() may be negative, which may cause the integer overflow problem. Fixes: 39b07096364a ("ima: Implement support for module-style appended signatures") Signed-off-by: Huaxin Lu <luhuaxin1@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-07-07ima: fix violation measurement list recordMimi Zohar1-3/+3
Although the violation digest in the IMA measurement list is always zeroes, the size of the digest should be based on the hash algorithm. Until recently the hash algorithm was hard coded to sha1. Fix the violation digest size included in the IMA measurement list. This is just a cosmetic change which should not affect attestation. Reported-by: Stefan Berger <stefanb@linux.ibm.com> Fixes: 09091c44cb73 ("ima: use IMA default hash algorithm for integrity violations") Tested-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-07-07apparmor: test: Remove some casts which are no-longer requiredDavid Gow1-6/+6
With some of the stricter type checking in KUnit's EXPECT macros removed, several casts in policy_unpack_test are no longer required. Remove the unnecessary casts, making the conditions clearer. Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Acked-by: John Johansen <john.johansen@canonical.com> Signed-off-by: David Gow <davidgow@google.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2022-07-01x86/kexec: Carry forward IMA measurement log on kexecJonathan McDowell1-1/+1
On kexec file load, the Integrity Measurement Architecture (IMA) subsystem may verify the IMA signature of the kernel and initramfs, and measure it. The command line parameters passed to the kernel in the kexec call may also be measured by IMA. A remote attestation service can verify a TPM quote based on the TPM event log, the IMA measurement list and the TPM PCR data. This can be achieved only if the IMA measurement log is carried over from the current kernel to the next kernel across the kexec call. PowerPC and ARM64 both achieve this using device tree with a "linux,ima-kexec-buffer" node. x86 platforms generally don't make use of device tree, so use the setup_data mechanism to pass the IMA buffer to the new kernel. Signed-off-by: Jonathan McDowell <noodles@fb.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> # IMA function definitions Link: https://lore.kernel.org/r/YmKyvlF3my1yWTvK@noodles-fedora-PC23Y6EG
2022-06-29x86/retbleed: Add fine grained Kconfig knobsPeter Zijlstra1-11/+0
Do fine-grained Kconfig for all the various retbleed parts. NOTE: if your compiler doesn't support return thunks this will silently 'upgrade' your mitigation to IBPB, you might not like this. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-26attr: port attribute changes to new typesChristian Brauner1-2/+2
Now that we introduced new infrastructure to increase the type safety for filesystems supporting idmapped mounts port the first part of the vfs over to them. This ports the attribute changes codepaths to rely on the new better helpers using a dedicated type. Before this change we used to take a shortcut and place the actual values that would be written to inode->i_{g,u}id into struct iattr. This had the advantage that we moved idmappings mostly out of the picture early on but it made reasoning about changes more difficult than it should be. The filesystem was never explicitly told that it dealt with an idmapped mount. The transition to the value that needed to be stored in inode->i_{g,u}id appeared way too early and increased the probability of bugs in various codepaths. We know place the same value in struct iattr no matter if this is an idmapped mount or not. The vfs will only deal with type safe vfs{g,u}id_t. This makes it massively safer to perform permission checks as the type will tell us what checks we need to perform and what helpers we need to use. Fileystems raising FS_ALLOW_IDMAP can't simply write ia_vfs{g,u}id to inode->i_{g,u}id since they are different types. Instead they need to use the dedicated vfs{g,u}id_to_k{g,u}id() helpers that map the vfs{g,u}id into the filesystem. The other nice effect is that filesystems like overlayfs don't need to care about idmappings explicitly anymore and can simply set up struct iattr accordingly directly. Link: https://lore.kernel.org/lkml/CAHk-=win6+ahs1EwLkcq8apqLi_1wXFWbrPf340zYEhObpz4jA@mail.gmail.com [1] Link: https://lore.kernel.org/r/20220621141454.2914719-9-brauner@kernel.org Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> CC: linux-fsdevel@vger.kernel.org Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-06-26security: pass down mount idmapping to setattr hookChristian Brauner2-5/+8
Before this change we used to take a shortcut and place the actual values that would be written to inode->i_{g,u}id into struct iattr. This had the advantage that we moved idmappings mostly out of the picture early on but it made reasoning about changes more difficult than it should be. The filesystem was never explicitly told that it dealt with an idmapped mount. The transition to the value that needed to be stored in inode->i_{g,u}id appeared way too early and increased the probability of bugs in various codepaths. We know place the same value in struct iattr no matter if this is an idmapped mount or not. The vfs will only deal with type safe vfs{g,u}id_t. This makes it massively safer to perform permission checks as the type will tell us what checks we need to perform and what helpers we need to use. Adapt the security_inode_setattr() helper to pass down the mount's idmapping to account for that change. Link: https://lore.kernel.org/r/20220621141454.2914719-8-brauner@kernel.org Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> CC: linux-fsdevel@vger.kernel.org Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-06-26fs: port to iattr ownership update helpersChristian Brauner1-2/+2
Earlier we introduced new helpers to abstract ownership update and remove code duplication. This converts all filesystems supporting idmapped mounts to make use of these new helpers. For now we always pass the initial idmapping which makes the idmapping functions these helpers call nops. This is done because we currently always pass the actual value to be written to i_{g,u}id via struct iattr. While this allowed us to treat the {g,u}id values in struct iattr as values that can be directly written to inode->i_{g,u}id it also increases the potential for confusion for filesystems. Now that we are have dedicated types to prevent this confusion we will ultimately only map the value from the idmapped mount into a filesystem value that can be written to inode->i_{g,u}id when the filesystem actually updates the inode. So pass down the initial idmapping until we finished that conversion at which point we pass down the mount's idmapping. No functional changes intended. Link: https://lore.kernel.org/r/20220621141454.2914719-6-brauner@kernel.org Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> CC: linux-fsdevel@vger.kernel.org Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-06-21selinux: selinux_add_opt() callers free memoryXiu Jianfeng1-7/+4
The selinux_add_opt() function may need to allocate memory for the mount options if none has already been allocated, but there is no need to free that memory on error as the callers handle that. Drop the existing kfree() on error to help increase consistency in the selinux_add_opt() error handling. This patch also changes selinux_add_opt() to return -EINVAL when the mount option value, @s, is NULL. It currently return -ENOMEM. Link: https://lore.kernel.org/lkml/20220611090550.135674-1-xiujianfeng@huawei.com/T/ Suggested-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> [PM: fix subject, rework commit description language] Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-06-16selinux: free contexts previously transferred in selinux_add_opt()Christian Göttsche1-7/+4
`selinux_add_opt()` stopped taking ownership of the passed context since commit 70f4169ab421 ("selinux: parse contexts for mount options early"). unreferenced object 0xffff888114dfd140 (size 64): comm "mount", pid 15182, jiffies 4295687028 (age 796.340s) hex dump (first 32 bytes): 73 79 73 74 65 6d 5f 75 3a 6f 62 6a 65 63 74 5f system_u:object_ 72 3a 74 65 73 74 5f 66 69 6c 65 73 79 73 74 65 r:test_filesyste backtrace: [<ffffffffa07dbef4>] kmemdup_nul+0x24/0x80 [<ffffffffa0d34253>] selinux_sb_eat_lsm_opts+0x293/0x560 [<ffffffffa0d13f08>] security_sb_eat_lsm_opts+0x58/0x80 [<ffffffffa0af1eb2>] generic_parse_monolithic+0x82/0x180 [<ffffffffa0a9c1a5>] do_new_mount+0x1f5/0x550 [<ffffffffa0a9eccb>] path_mount+0x2ab/0x1570 [<ffffffffa0aa019e>] __x64_sys_mount+0x20e/0x280 [<ffffffffa1f47124>] do_syscall_64+0x34/0x80 [<ffffffffa200007e>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 unreferenced object 0xffff888108e71640 (size 64): comm "fsmount", pid 7607, jiffies 4295044974 (age 1601.016s) hex dump (first 32 bytes): 73 79 73 74 65 6d 5f 75 3a 6f 62 6a 65 63 74 5f system_u:object_ 72 3a 74 65 73 74 5f 66 69 6c 65 73 79 73 74 65 r:test_filesyste backtrace: [<ffffffff861dc2b1>] memdup_user+0x21/0x90 [<ffffffff861dc367>] strndup_user+0x47/0xa0 [<ffffffff864f6965>] __do_sys_fsconfig+0x485/0x9f0 [<ffffffff87940124>] do_syscall_64+0x34/0x80 [<ffffffff87a0007e>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 Cc: stable@vger.kernel.org Fixes: 70f4169ab421 ("selinux: parse contexts for mount options early") Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-06-15Revert "evm: Fix memleak in init_desc"Xiu Jianfeng1-5/+2
This reverts commit ccf11dbaa07b328fa469415c362d33459c140a37. Commit ccf11dbaa07b ("evm: Fix memleak in init_desc") said there is memleak in init_desc. That may be incorrect, as we can see, tmp_tfm is saved in one of the two global variables hmac_tfm or evm_tfm[hash_algo], then if init_desc is called next time, there is no need to alloc tfm again, so in the error path of kmalloc desc or crypto_shash_init(desc), It is not a problem without freeing tmp_tfm. And also that commit did not reset the global variable to NULL after freeing tmp_tfm and this makes *tfm a dangling pointer which may cause a UAF issue. Reported-by: Guozihua (Scott) <guozihua@huawei.com> Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-06-15selinux: Add boundary check in put_entry()Xiu Jianfeng1-0/+2
Just like next_entry(), boundary check is necessary to prevent memory out-of-bound access. Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-06-14selinux: fix memleak in security_read_state_kernel()Xiu Jianfeng1-1/+8
In this function, it directly returns the result of __security_read_policy without freeing the allocated memory in *data, cause memory leak issue, so free the memory if __security_read_policy failed. Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> [PM: subject line tweak] Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-06-10selinux: fix typos in commentsJonas Lindner2-3/+3
Signed-off-by: Jonas Lindner <jolindner@gmx.de> [PM: fixed duplicated subject line] Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-06-08KEYS: trusted: tpm2: Fix migratable logicDavid Safford1-2/+2
When creating (sealing) a new trusted key, migratable trusted keys have the FIXED_TPM and FIXED_PARENT attributes set, and non-migratable keys don't. This is backwards, and also causes creation to fail when creating a migratable key under a migratable parent. (The TPM thinks you are trying to seal a non-migratable blob under a migratable parent.) The following simple patch fixes the logic, and has been tested for all four combinations of migratable and non-migratable trusted keys and parent storage keys. With this logic, you will get a proper failure if you try to create a non-migratable trusted key under a migratable parent storage key, and all other combinations work correctly. Cc: stable@vger.kernel.org # v5.13+ Fixes: e5fb5d2c5a03 ("security: keys: trusted: Make sealed key properly interoperable") Signed-off-by: David Safford <david.safford@gmail.com> Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-06-08selinux: drop unnecessary NULL checkChristian Göttsche1-1/+1
Commit e3489f8974e1 ("selinux: kill selinux_sb_get_mnt_opts()") introduced a NULL check on the context after a successful call to security_sid_to_context(). This is on the one hand redundant after checking for success and on the other hand insufficient on an actual NULL pointer, since the context is passed to seq_escape() leading to a call of strlen() on it. Reported by Clang analyzer: In file included from security/selinux/hooks.c:28: In file included from ./include/linux/tracehook.h:50: In file included from ./include/linux/memcontrol.h:13: In file included from ./include/linux/cgroup.h:18: ./include/linux/seq_file.h:136:25: warning: Null pointer passed as 1st argument to string length function [unix.cstring.NullArg] seq_escape_mem(m, src, strlen(src), flags, esc); ^~~~~~~~~~~ Signed-off-by: Christian Göttsche <cgzones@googlemail.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-06-07selinux: add __randomize_layout to selinux_audit_dataGONG, Ruiqi1-1/+1
Randomize the layout of struct selinux_audit_data as suggested in [1], since it contains a pointer to struct selinux_state, an already randomized strucure. [1]: https://github.com/KSPP/linux/issues/188 Signed-off-by: GONG, Ruiqi <gongruiqi1@huawei.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-06-05Merge tag 'pull-18-rc1-work.mount' of ↵Linus Torvalds1-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull mount handling updates from Al Viro: "Cleanups (and one fix) around struct mount handling. The fix is usermode_driver.c one - once you've done kern_mount(), you must kern_unmount(); simple mntput() will end up with a leak. Several failure exits in there messed up that way... In practice you won't hit those particular failure exits without fault injection, though" * tag 'pull-18-rc1-work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: move mount-related externs from fs.h to mount.h blob_to_mnt(): kern_unmount() is needed to undo kern_mount() m->mnt_root->d_inode->i_sb is a weird way to spell m->mnt_sb... linux/mount.h: trim includes uninline may_mount() and don't opencode it in fspick(2)/fsopen(2)
2022-05-25Merge tag 'linux-kselftest-kunit-5.19-rc1' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull KUnit updates from Shuah Khan: "Several fixes, cleanups, and enhancements to tests and framework: - introduce _NULL and _NOT_NULL macros to pointer error checks - rework kunit_resource allocation policy to fix memory leaks when caller doesn't specify free() function to be used when allocating memory using kunit_add_resource() and kunit_alloc_resource() funcs. - add ability to specify suite-level init and exit functions" * tag 'linux-kselftest-kunit-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (41 commits) kunit: tool: Use qemu-system-i386 for i386 runs kunit: fix executor OOM error handling logic on non-UML kunit: tool: update riscv QEMU config with new serial dependency kcsan: test: use new suite_{init,exit} support kunit: tool: Add list of all valid test configs on UML kunit: take `kunit_assert` as `const` kunit: tool: misc cleanups kunit: tool: minor cosmetic cleanups in kunit_parser.py kunit: tool: make parser stop overwriting status of suites w/ no_tests kunit: tool: remove dead parse_crash_in_log() logic kunit: tool: print clearer error message when there's no TAP output kunit: tool: stop using a shell to run kernel under QEMU kunit: tool: update test counts summary line format kunit: bail out of test filtering logic quicker if OOM lib/Kconfig.debug: change KUnit tests to default to KUNIT_ALL_TESTS kunit: Rework kunit_resource allocation policy kunit: fix debugfs code to use enum kunit_status, not bool kfence: test: use new suite_{init/exit} support, add .kunitconfig kunit: add ability to specify suite-level init and exit functions kunit: rename print_subtest_{start,end} for clarity (s/subtest/suite) ...
2022-05-24Merge tag 'integrity-v5.19' of ↵Linus Torvalds16-52/+395
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull IMA updates from Mimi Zohar: "New is IMA support for including fs-verity file digests and signatures in the IMA measurement list as well as verifying the fs-verity file digest based signatures, both based on policy. In addition, are two bug fixes: - avoid reading UEFI variables, which cause a page fault, on Apple Macs with T2 chips. - remove the original "ima" template Kconfig option to address a boot command line ordering issue. The rest is a mixture of code/documentation cleanup" * tag 'integrity-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: integrity: Fix sparse warnings in keyring_handler evm: Clean up some variables evm: Return INTEGRITY_PASS for enum integrity_status value '0' efi: Do not import certificates from UEFI Secure Boot for T2 Macs fsverity: update the documentation ima: support fs-verity file digest based version 3 signatures ima: permit fsverity's file digests in the IMA measurement list ima: define a new template field named 'd-ngv2' and templates fs-verity: define a function to return the integrity protected file digest ima: use IMA default hash algorithm for integrity violations ima: fix 'd-ng' comments and documentation ima: remove the IMA_TEMPLATE Kconfig option ima: remove redundant initialization of pointer 'file'.
2022-05-24Merge tag 'tpmdd-next-v5.19-rc1' of ↵Linus Torvalds6-43/+174
git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd Pull tpm updates from Jarkko Sakkinen: - Tightened validation of key hashes for SYSTEM_BLACKLIST_HASH_LIST. An invalid hash format causes a compilation error. Previously, they got included to the kernel binary but were silently ignored at run-time. - Allow root user to append new hashes to the blacklist keyring. - Trusted keys backed with Cryptographic Acceleration and Assurance Module (CAAM), which part of some of the new NXP's SoC's. Now there is total three hardware backends for trusted keys: TPM, ARM TEE and CAAM. - A scattered set of fixes and small improvements for the TPM driver. * tag 'tpmdd-next-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd: MAINTAINERS: add KEYS-TRUSTED-CAAM doc: trusted-encrypted: describe new CAAM trust source KEYS: trusted: Introduce support for NXP CAAM-based trusted keys crypto: caam - add in-kernel interface for blob generator crypto: caam - determine whether CAAM supports blob encap/decap KEYS: trusted: allow use of kernel RNG for key material KEYS: trusted: allow use of TEE as backend without TCG_TPM support tpm: Add field upgrade mode support for Infineon TPM2 modules tpm: Fix buffer access in tpm2_get_tpm_pt() char: tpm: cr50_i2c: Suppress duplicated error message in .remove() tpm: cr50: Add new device/vendor ID 0x504a6666 tpm: Remove read16/read32/write32 calls from tpm_tis_phy_ops tpm: ibmvtpm: Correct the return value in tpm_ibmvtpm_probe() tpm/tpm_ftpm_tee: Return true/false (not 1/0) from bool functions certs: Explain the rationale to call panic() certs: Allow root user to append signed hashes to the blacklist keyring certs: Check that builtin blacklist hashes are valid certs: Make blacklist_vet_description() more strict certs: Factor out the blacklist hash creation tools/certs: Add print-cert-tbs-hash.sh
2022-05-24Merge tag 'Smack-for-5.19' of https://github.com/cschaufler/smack-nextLinus Torvalds1-1/+0
Pull smack update from Casey Schaufler: "A single change to remove a pointless assignment" * tag 'Smack-for-5.19' of https://github.com/cschaufler/smack-next: smack: Remove redundant assignments
2022-05-24Merge tag 'landlock-5.19-rc1' of ↵Linus Torvalds14-286/+848
git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux Pull Landlock updates from Mickaël Salaün: - improve the path_rename LSM hook implementations for RENAME_EXCHANGE; - fix a too-restrictive filesystem control for a rare corner case; - set the nested sandbox limitation to 16 layers; - add a new LANDLOCK_ACCESS_FS_REFER access right to properly handle file reparenting (i.e. full rename and link support); - add new tests and documentation; - format code with clang-format to make it easier to maintain and contribute. * tag 'landlock-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux: (30 commits) landlock: Explain how to support Landlock landlock: Add design choices documentation for filesystem access rights landlock: Document good practices about filesystem policies landlock: Document LANDLOCK_ACCESS_FS_REFER and ABI versioning samples/landlock: Add support for file reparenting selftests/landlock: Add 11 new test suites dedicated to file reparenting landlock: Add support for file reparenting with LANDLOCK_ACCESS_FS_REFER LSM: Remove double path_rename hook calls for RENAME_EXCHANGE landlock: Move filesystem helpers and add a new one landlock: Fix same-layer rule unions landlock: Create find_rule() from unmask_layers() landlock: Reduce the maximum number of layers to 16 landlock: Define access_mask_t to enforce a consistent access mask size selftests/landlock: Test landlock_create_ruleset(2) argument check ordering landlock: Change landlock_restrict_self(2) check ordering landlock: Change landlock_add_rule(2) argument check ordering selftests/landlock: Add tests for O_PATH selftests/landlock: Fully test file rename with "remove" access selftests/landlock: Extend access right tests to directories selftests/landlock: Add tests for unknown access rights ...
2022-05-24Merge tag 'selinux-pr-20220523' of ↵Linus Torvalds21-81/+93
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "We've got twelve patches queued for v5.19, with most being fairly minor. The highlights are below: - The checkreqprot and runtime disable knobs have been deprecated for some time with no active users that we can find. In an effort to move things along we are adding a pause when the knobs are used to help make the deprecation more noticeable in case anyone is still using these hacks in the shadows. - We've added the anonymous inode class name to the AVC audit records when anonymous inodes are involved. This should make writing policy easier when anonymous inodes are involved. - More constification work. This is fairly straightforward and the source of most of the diffstat. - The usual minor cleanups: remove unnecessary assignments, assorted style/checkpatch fixes, kdoc fixes, macro while-loop encapsulations, #include tweaks, etc" * tag 'selinux-pr-20220523' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: security: declare member holding string literal const selinux: log anon inode class name selinux: declare data arrays const selinux: fix indentation level of mls_ops block selinux: include necessary headers in headers selinux: avoid extra semicolon selinux: update parameter documentation selinux: resolve checkpatch errors selinux: don't sleep when CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE is true selinux: checkreqprot is deprecated, add some ssleep() discomfort selinux: runtime disable is deprecated, add some ssleep() discomfort selinux: Remove redundant assignments
2022-05-24Merge tag 'kernel-hardening-v5.19-rc1' of ↵Linus Torvalds5-58/+115
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull kernel hardening updates from Kees Cook: - usercopy hardening expanded to check other allocation types (Matthew Wilcox, Yuanzheng Song) - arm64 stackleak behavioral improvements (Mark Rutland) - arm64 CFI code gen improvement (Sami Tolvanen) - LoadPin LSM block dev API adjustment (Christoph Hellwig) - Clang randstruct support (Bill Wendling, Kees Cook) * tag 'kernel-hardening-v5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (34 commits) loadpin: stop using bdevname mm: usercopy: move the virt_addr_valid() below the is_vmalloc_addr() gcc-plugins: randstruct: Remove cast exception handling af_unix: Silence randstruct GCC plugin warning niu: Silence randstruct warnings big_keys: Use struct for internal payload gcc-plugins: Change all version strings match kernel randomize_kstack: Improve docs on requirements/rationale lkdtm/stackleak: fix CONFIG_GCC_PLUGIN_STACKLEAK=n arm64: entry: use stackleak_erase_on_task_stack() stackleak: add on/off stack variants lkdtm/stackleak: check stack boundaries lkdtm/stackleak: prevent unexpected stack usage lkdtm/stackleak: rework boundary management lkdtm/stackleak: avoid spurious failure stackleak: rework poison scanning stackleak: rework stack high bound handling stackleak: clarify variable names stackleak: rework stack low bound handling stackleak: remove redundant check ...
2022-05-24lockdown: also lock down previous kgdb useDaniel Thompson1-0/+2
KGDB and KDB allow read and write access to kernel memory, and thus should be restricted during lockdown. An attacker with access to a serial port (for example, via a hypervisor console, which some cloud vendors provide over the network) could trigger the debugger so it is important that the debugger respect the lockdown mode when/if it is triggered. Fix this by integrating lockdown into kdb's existing permissions mechanism. Unfortunately kgdb does not have any permissions mechanism (although it certainly could be added later) so, for now, kgdb is simply and brutally disabled by immediately exiting the gdb stub without taking any action. For lockdowns established early in the boot (e.g. the normal case) then this should be fine but on systems where kgdb has set breakpoints before the lockdown is enacted than "bad things" will happen. CVE: CVE-2022-21499 Co-developed-by: Stephen Brennan <stephen.s.brennan@oracle.com> Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-05-23smack: Remove redundant assignmentsMichal Orzel1-1/+0
Get rid of redundant assignments which end up in values not being read either because they are overwritten or the function ends. Reported by clang-tidy [deadcode.DeadStores] Signed-off-by: Michal Orzel <michalorzel.eng@gmail.com> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
2022-05-23KEYS: trusted: Introduce support for NXP CAAM-based trusted keysAhmad Fatoum4-2/+97
The Cryptographic Acceleration and Assurance Module (CAAM) is an IP core built into many newer i.MX and QorIQ SoCs by NXP. The CAAM does crypto acceleration, hardware number generation and has a blob mechanism for encapsulation/decapsulation of sensitive material. This blob mechanism depends on a device specific random 256-bit One Time Programmable Master Key that is fused in each SoC at manufacturing time. This key is unreadable and can only be used by the CAAM for AES encryption/decryption of user data. This makes it a suitable backend (source) for kernel trusted keys. Previous commits generalized trusted keys to support multiple backends and added an API to access the CAAM blob mechanism. Based on these, provide the necessary glue to use the CAAM for trusted keys. Reviewed-by: David Gstir <david@sigma-star.at> Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Tim Harvey <tharvey@gateworks.com> Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> Tested-by: Pankaj Gupta <pankaj.gupta@nxp.com> Tested-by: Michael Walle <michael@walle.cc> # on ls1028a (non-E and E) Tested-by: John Ernberg <john.ernberg@actia.se> # iMX8QXP Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-05-23KEYS: trusted: allow use of kernel RNG for key materialAhmad Fatoum1-1/+34
The two existing trusted key sources don't make use of the kernel RNG, but instead let the hardware doing the sealing/unsealing also generate the random key material. However, both users and future backends may want to place less trust into the quality of the trust source's random number generator and instead reuse the kernel entropy pool, which can be seeded from multiple entropy sources. Make this possible by adding a new trusted.rng parameter, that will force use of the kernel RNG. In its absence, it's up to the trust source to decide, which random numbers to use, maintaining the existing behavior. Suggested-by: Jarkko Sakkinen <jarkko@kernel.org> Acked-by: Sumit Garg <sumit.garg@linaro.org> Acked-by: Pankaj Gupta <pankaj.gupta@nxp.com> Reviewed-by: David Gstir <david@sigma-star.at> Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Pankaj Gupta <pankaj.gupta@nxp.com> Tested-by: Michael Walle <michael@walle.cc> # on ls1028a (non-E and E) Tested-by: John Ernberg <john.ernberg@actia.se> # iMX8QXP Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-05-23KEYS: trusted: allow use of TEE as backend without TCG_TPM supportAhmad Fatoum4-17/+42
With recent rework, trusted keys are no longer limited to TPM as trust source. The Kconfig symbol is unchanged however leading to a few issues: - TCG_TPM is required, even if only TEE is to be used - Enabling TCG_TPM, but excluding it from available trusted sources is not possible - TEE=m && TRUSTED_KEYS=y will lead to TEE support being silently dropped, which is not the best user experience Remedy these issues by introducing two new boolean Kconfig symbols: TRUSTED_KEYS_TPM and TRUSTED_KEYS_TEE with the appropriate dependencies. Any new code depending on the TPM trusted key backend in particular or symbols exported by it will now need to explicitly state that it depends on TRUSTED_KEYS && TRUSTED_KEYS_TPM The latter to ensure the dependency is built and the former to ensure it's reachable for module builds. There are no such users yet. Reviewed-by: Sumit Garg <sumit.garg@linaro.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> Tested-by: Pankaj Gupta <pankaj.gupta@nxp.com> Tested-by: Andreas Rammhold <andreas@rammhold.de> Tested-by: Tim Harvey <tharvey@gateworks.com> Tested-by: Michael Walle <michael@walle.cc> # on ls1028a (non-E and E) Tested-by: John Ernberg <john.ernberg@actia.se> # iMX8QXP Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-05-23certs: Factor out the blacklist hash creationMickaël Salaün1-24/+2
Factor out the blacklist hash creation with the get_raw_hash() helper. This also centralize the "tbs" and "bin" prefixes and make them private, which help to manage them consistently. Cc: David Howells <dhowells@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Snowberg <eric.snowberg@oracle.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com> Link: https://lore.kernel.org/r/20210712170313.884724-5-mic@digikod.net Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2022-05-23landlock: Add support for file reparenting with LANDLOCK_ACCESS_FS_REFERMickaël Salaün3-76/+528
Add a new LANDLOCK_ACCESS_FS_REFER access right to enable policy writers to allow sandboxed processes to link and rename files from and to a specific set of file hierarchies. This access right should be composed with LANDLOCK_ACCESS_FS_MAKE_* for the destination of a link or rename, and with LANDLOCK_ACCESS_FS_REMOVE_* for a source of a rename. This lift a Landlock limitation that always denied changing the parent of an inode. Renaming or linking to the same directory is still always allowed, whatever LANDLOCK_ACCESS_FS_REFER is used or not, because it is not considered a threat to user data. However, creating multiple links or renaming to a different parent directory may lead to privilege escalations if not handled properly. Indeed, we must be sure that the source doesn't gain more privileges by being accessible from the destination. This is handled by making sure that the source hierarchy (including the referenced file or directory itself) restricts at least as much the destination hierarchy. If it is not the case, an EXDEV error is returned, making it potentially possible for user space to copy the file hierarchy instead of moving or linking it. Instead of creating different access rights for the source and the destination, we choose to make it simple and consistent for users. Indeed, considering the previous constraint, it would be weird to require such destination access right to be also granted to the source (to make it a superset). Moreover, RENAME_EXCHANGE would also add to the confusion because of paths being both a source and a destination. See the provided documentation for additional details. New tests are provided with a following commit. Reviewed-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mickaël Salaün <mic@digikod.net> Link: https://lore.kernel.org/r/20220506161102.525323-8-mic@digikod.net
2022-05-23LSM: Remove double path_rename hook calls for RENAME_EXCHANGEMickaël Salaün4-15/+46
In order to be able to identify a file exchange with renameat2(2) and RENAME_EXCHANGE, which will be useful for Landlock [1], propagate the rename flags to LSMs. This may also improve performance because of the switch from two set of LSM hook calls to only one, and because LSMs using this hook may optimize the double check (e.g. only one lock, reduce the number of path walks). AppArmor, Landlock and Tomoyo are updated to leverage this change. This should not change the current behavior (same check order), except (different level of) speed boosts. [1] https://lore.kernel.org/r/20220221212522.320243-1-mic@digikod.net Cc: James Morris <jmorris@namei.org> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Serge E. Hallyn <serge@hallyn.com> Acked-by: John Johansen <john.johansen@canonical.com> Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mickaël Salaün <mic@digikod.net> Link: https://lore.kernel.org/r/20220506161102.525323-7-mic@digikod.net
2022-05-23landlock: Move filesystem helpers and add a new oneMickaël Salaün1-41/+46
Move the SB_NOUSER and IS_PRIVATE dentry check to a standalone is_nouser_or_private() helper. This will be useful for a following commit. Move get_mode_access() and maybe_remove() to make them usable by new code provided by a following commit. Reviewed-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mickaël Salaün <mic@digikod.net> Link: https://lore.kernel.org/r/20220506161102.525323-6-mic@digikod.net
2022-05-23landlock: Fix same-layer rule unionsMickaël Salaün2-26/+54
The original behavior was to check if the full set of requested accesses was allowed by at least a rule of every relevant layer. This didn't take into account requests for multiple accesses and same-layer rules allowing the union of these accesses in a complementary way. As a result, multiple accesses requested on a file hierarchy matching rules that, together, allowed these accesses, but without a unique rule allowing all of them, was illegitimately denied. This case should be rare in practice and it can only be triggered by the path_rename or file_open hook implementations. For instance, if, for the same layer, a rule allows execution beneath /a/b and another rule allows read beneath /a, requesting access to read and execute at the same time for /a/b should be allowed for this layer. This was an inconsistency because the union of same-layer rule accesses was already allowed if requested once at a time anyway. This fix changes the way allowed accesses are gathered over a path walk. To take into account all these rule accesses, we store in a matrix all layer granting the set of requested accesses, according to the handled accesses. To avoid heap allocation, we use an array on the stack which is 2*13 bytes. A following commit bringing the LANDLOCK_ACCESS_FS_REFER access right will increase this size to reach 112 bytes (2*14*4) in case of link or rename actions. Add a new layout1.layer_rule_unions test to check that accesses from different rules pertaining to the same layer are ORed in a file hierarchy. Also test that it is not the case for rules from different layers. Reviewed-by: Paul Moore <paul@paul-moore.com> Link: https://lore.kernel.org/r/20220506161102.525323-5-mic@digikod.net Cc: stable@vger.kernel.org Signed-off-by: Mickaël Salaün <mic@digikod.net>
2022-05-23landlock: Create find_rule() from unmask_layers()Mickaël Salaün1-13/+28
This refactoring will be useful in a following commit. Reviewed-by: Paul Moore <paul@paul-moore.com> Link: https://lore.kernel.org/r/20220506161102.525323-4-mic@digikod.net Cc: stable@vger.kernel.org Signed-off-by: Mickaël Salaün <mic@digikod.net>
2022-05-23landlock: Reduce the maximum number of layers to 16Mickaël Salaün3-11/+12
The maximum number of nested Landlock domains is currently 64. Because of the following fix and to help reduce the stack size, let's reduce it to 16. This seems large enough for a lot of use cases (e.g. sandboxed init service, spawning a sandboxed SSH service, in nested sandboxed containers). Reducing the number of nested domains may also help to discover misuse of Landlock (e.g. creating a domain per rule). Add and use a dedicated layer_mask_t typedef to fit with the number of layers. This might be useful when changing it and to keep it consistent with the maximum number of layers. Reviewed-by: Paul Moore <paul@paul-moore.com> Link: https://lore.kernel.org/r/20220506161102.525323-3-mic@digikod.net Cc: stable@vger.kernel.org Signed-off-by: Mickaël Salaün <mic@digikod.net>
2022-05-23landlock: Define access_mask_t to enforce a consistent access mask sizeMickaël Salaün5-15/+30
Create and use the access_mask_t typedef to enforce a consistent access mask size and uniformly use a 16-bits type. This will helps transition to a 32-bits value one day. Add a build check to make sure all (filesystem) access rights fit in. This will be extended with a following commit. Reviewed-by: Paul Moore <paul@paul-moore.com> Link: https://lore.kernel.org/r/20220506161102.525323-2-mic@digikod.net Cc: stable@vger.kernel.org Signed-off-by: Mickaël Salaün <mic@digikod.net>
2022-05-23landlock: Change landlock_restrict_self(2) check orderingMickaël Salaün1-4/+4
According to the Landlock goal to be a security feature available to unprivileges processes, it makes more sense to first check for no_new_privs before checking anything else (i.e. syscall arguments). Merge inval_fd_enforce and unpriv_enforce_without_no_new_privs tests into the new restrict_self_checks_ordering. This is similar to the previous commit checking other syscalls. Link: https://lore.kernel.org/r/20220506160820.524344-10-mic@digikod.net Cc: stable@vger.kernel.org Signed-off-by: Mickaël Salaün <mic@digikod.net>
2022-05-23landlock: Change landlock_add_rule(2) argument check orderingMickaël Salaün1-9/+13
This makes more sense to first check the ruleset FD and then the rule attribute. It will be useful to factor out code for other rule types. Add inval_add_rule_arguments tests, extension of empty_path_beneath_attr tests, to also check error ordering for landlock_add_rule(2). Link: https://lore.kernel.org/r/20220506160820.524344-9-mic@digikod.net Cc: stable@vger.kernel.org Signed-off-by: Mickaël Salaün <mic@digikod.net>
2022-05-23landlock: Fix landlock_add_rule(2) documentationMickaël Salaün1-4/+3
It is not mandatory to pass a file descriptor obtained with the O_PATH flag. Also, replace rule's accesses with ruleset's accesses. Link: https://lore.kernel.org/r/20220506160820.524344-2-mic@digikod.net Cc: stable@vger.kernel.org Signed-off-by: Mickaël Salaün <mic@digikod.net>
2022-05-20move mount-related externs from fs.h to mount.hAl Viro1-0/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-05-18selinux: fix bad cleanup on error in hashtab_duplicate()Ondrej Mosnacek1-1/+2
The code attempts to free the 'new' pointer using kmem_cache_free(), which is wrong because this function isn't responsible of freeing it. Instead, the function should free new->htable and clear the contents of *new (to prevent double-free). Cc: stable@vger.kernel.org Fixes: c7c556f1e81b ("selinux: refactor changing booleans") Reported-by: Wander Lairson Costa <wander@redhat.com> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2022-05-17loadpin: stop using bdevnameChristoph Hellwig1-4/+1
Use the %pg format specifier to save on stack consuption and code size. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20220512062014.1826835-1-hch@lst.de
2022-05-17big_keys: Use struct for internal payloadKees Cook1-37/+36
The randstruct GCC plugin gets upset when it sees struct path (which is randomized) being assigned from a "void *" (which it cannot type-check). There's no need for these casts, as the entire internal payload use is following a normal struct layout. Convert the enum-based void * offset dereferencing to the new big_key_payload struct. No meaningful machine code changes result after this change, and source readability is improved. Drop the randstruct exception now that there is no "confusing" cross-type assignment. Cc: David Howells <dhowells@redhat.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: linux-hardening@vger.kernel.org Cc: keyrings@vger.kernel.org Cc: linux-security-module@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
2022-05-17integrity: Fix sparse warnings in keyring_handlerStefan Berger1-3/+3
Fix the following sparse warnings: CHECK security/integrity/platform_certs/keyring_handler.c security/integrity/platform_certs/keyring_handler.c:76:16: warning: Using plain integer as NULL pointer security/integrity/platform_certs/keyring_handler.c:91:16: warning: Using plain integer as NULL pointer security/integrity/platform_certs/keyring_handler.c:106:16: warning: Using plain integer as NULL pointer Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-05-16evm: Clean up some variablesStefan Berger2-4/+1
Make hmac_tfm static since it's not used anywhere else besides the file it is in. Remove declaration of hash_tfm since it doesn't exist. Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-05-16evm: Return INTEGRITY_PASS for enum integrity_status value '0'Stefan Berger1-1/+1
Return INTEGRITY_PASS for the enum integrity_status rather than 0. Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-05-15efi: Do not import certificates from UEFI Secure Boot for T2 MacsAditya Garg2-0/+41
On Apple T2 Macs, when Linux attempts to read the db and dbx efi variables at early boot to load UEFI Secure Boot certificates, a page fault occurs in Apple firmware code and EFI runtime services are disabled with the following logs: [Firmware Bug]: Page fault caused by firmware at PA: 0xffffb1edc0068000 WARNING: CPU: 3 PID: 104 at arch/x86/platform/efi/quirks.c:735 efi_crash_gracefully_on_page_fault+0x50/0xf0 (Removed some logs from here) Call Trace: <TASK> page_fault_oops+0x4f/0x2c0 ? search_bpf_extables+0x6b/0x80 ? search_module_extables+0x50/0x80 ? search_exception_tables+0x5b/0x60 kernelmode_fixup_or_oops+0x9e/0x110 __bad_area_nosemaphore+0x155/0x190 bad_area_nosemaphore+0x16/0x20 do_kern_addr_fault+0x8c/0xa0 exc_page_fault+0xd8/0x180 asm_exc_page_fault+0x1e/0x30 (Removed some logs from here) ? __efi_call+0x28/0x30 ? switch_mm+0x20/0x30 ? efi_call_rts+0x19a/0x8e0 ? process_one_work+0x222/0x3f0 ? worker_thread+0x4a/0x3d0 ? kthread+0x17a/0x1a0 ? process_one_work+0x3f0/0x3f0 ? set_kthread_struct+0x40/0x40 ? ret_from_fork+0x22/0x30 </TASK> ---[ end trace 1f82023595a5927f ]--- efi: Froze efi_rts_wq and disabled EFI Runtime Services integrity: Couldn't get size: 0x8000000000000015 integrity: MODSIGN: Couldn't get UEFI db list efi: EFI Runtime Services are disabled! integrity: Couldn't get size: 0x8000000000000015 integrity: Couldn't get UEFI dbx list integrity: Couldn't get size: 0x8000000000000015 integrity: Couldn't get mokx list integrity: Couldn't get size: 0x80000000 So we avoid reading these UEFI variables and thus prevent the crash. Cc: stable@vger.kernel.org Signed-off-by: Aditya Garg <gargaditya08@live.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>