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authorLinus Torvalds <torvalds@linux-foundation.org>2019-07-17 18:58:04 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2019-07-17 18:58:04 +0300
commit57a8ec387e1441ea5e1232bc0749fb99a8cba7e7 (patch)
treeb5fb03fc6bc5754de8b5b1f8b0e4f36d67c8315c /kernel
parent0a8ad0ffa4d80a544f6cbff703bf6394339afcdf (diff)
parent43e11fa2d1d3b6e35629fa556eb7d571edba2010 (diff)
downloadlinux-57a8ec387e1441ea5e1232bc0749fb99a8cba7e7.tar.xz
Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton: "VM: - z3fold fixes and enhancements by Henry Burns and Vitaly Wool - more accurate reclaimed slab caches calculations by Yafang Shao - fix MAP_UNINITIALIZED UAPI symbol to not depend on config, by Christoph Hellwig - !CONFIG_MMU fixes by Christoph Hellwig - new novmcoredd parameter to omit device dumps from vmcore, by Kairui Song - new test_meminit module for testing heap and pagealloc initialization, by Alexander Potapenko - ioremap improvements for huge mappings, by Anshuman Khandual - generalize kprobe page fault handling, by Anshuman Khandual - device-dax hotplug fixes and improvements, by Pavel Tatashin - enable synchronous DAX fault on powerpc, by Aneesh Kumar K.V - add pte_devmap() support for arm64, by Robin Murphy - unify locked_vm accounting with a helper, by Daniel Jordan - several misc fixes core/lib: - new typeof_member() macro including some users, by Alexey Dobriyan - make BIT() and GENMASK() available in asm, by Masahiro Yamada - changed LIST_POISON2 on x86_64 to 0xdead000000000122 for better code generation, by Alexey Dobriyan - rbtree code size optimizations, by Michel Lespinasse - convert struct pid count to refcount_t, by Joel Fernandes get_maintainer.pl: - add --no-moderated switch to skip moderated ML's, by Joe Perches misc: - ptrace PTRACE_GET_SYSCALL_INFO interface - coda updates - gdb scripts, various" [ Using merge message suggestion from Vlastimil Babka, with some editing - Linus ] * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (100 commits) fs/select.c: use struct_size() in kmalloc() mm: add account_locked_vm utility function arm64: mm: implement pte_devmap support mm: introduce ARCH_HAS_PTE_DEVMAP mm: clean up is_device_*_page() definitions mm/mmap: move common defines to mman-common.h mm: move MAP_SYNC to asm-generic/mman-common.h device-dax: "Hotremove" persistent memory that is used like normal RAM mm/hotplug: make remove_memory() interface usable device-dax: fix memory and resource leak if hotplug fails include/linux/lz4.h: fix spelling and copy-paste errors in documentation ipc/mqueue.c: only perform resource calculation if user valid include/asm-generic/bug.h: fix "cut here" for WARN_ON for __WARN_TAINT architectures scripts/gdb: add helpers to find and list devices scripts/gdb: add lx-genpd-summary command drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl kernel/pid.c: convert struct pid count to refcount_t drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings select: shift restore_saved_sigmask_unless() into poll_select_copy_remaining() select: change do_poll() to return -ERESTARTNOHAND rather than -EINTR ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/pid.c9
-rw-r--r--kernel/ptrace.c101
-rw-r--r--kernel/signal.c69
-rw-r--r--kernel/sysctl.c18
4 files changed, 132 insertions, 65 deletions
diff --git a/kernel/pid.c b/kernel/pid.c
index 16263b526560..0a9f2e437217 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -37,14 +37,14 @@
#include <linux/init_task.h>
#include <linux/syscalls.h>
#include <linux/proc_ns.h>
-#include <linux/proc_fs.h>
+#include <linux/refcount.h>
#include <linux/anon_inodes.h>
#include <linux/sched/signal.h>
#include <linux/sched/task.h>
#include <linux/idr.h>
struct pid init_struct_pid = {
- .count = ATOMIC_INIT(1),
+ .count = REFCOUNT_INIT(1),
.tasks = {
{ .first = NULL },
{ .first = NULL },
@@ -108,8 +108,7 @@ void put_pid(struct pid *pid)
return;
ns = pid->numbers[pid->level].ns;
- if ((atomic_read(&pid->count) == 1) ||
- atomic_dec_and_test(&pid->count)) {
+ if (refcount_dec_and_test(&pid->count)) {
kmem_cache_free(ns->pid_cachep, pid);
put_pid_ns(ns);
}
@@ -212,7 +211,7 @@ struct pid *alloc_pid(struct pid_namespace *ns)
}
get_pid_ns(ns);
- atomic_set(&pid->count, 1);
+ refcount_set(&pid->count, 1);
for (type = 0; type < PIDTYPE_MAX; ++type)
INIT_HLIST_HEAD(&pid->tasks[type]);
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 83a531cea2f3..cb9ddcc08119 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -32,6 +32,8 @@
#include <linux/compat.h>
#include <linux/sched/signal.h>
+#include <asm/syscall.h> /* for syscall_get_* */
+
/*
* Access another process' address space via ptrace.
* Source/target buffer must be kernel space,
@@ -897,7 +899,100 @@ static int ptrace_regset(struct task_struct *task, int req, unsigned int type,
* to ensure no machine forgets it.
*/
EXPORT_SYMBOL_GPL(task_user_regset_view);
-#endif
+
+static unsigned long
+ptrace_get_syscall_info_entry(struct task_struct *child, struct pt_regs *regs,
+ struct ptrace_syscall_info *info)
+{
+ unsigned long args[ARRAY_SIZE(info->entry.args)];
+ int i;
+
+ info->op = PTRACE_SYSCALL_INFO_ENTRY;
+ info->entry.nr = syscall_get_nr(child, regs);
+ syscall_get_arguments(child, regs, args);
+ for (i = 0; i < ARRAY_SIZE(args); i++)
+ info->entry.args[i] = args[i];
+
+ /* args is the last field in struct ptrace_syscall_info.entry */
+ return offsetofend(struct ptrace_syscall_info, entry.args);
+}
+
+static unsigned long
+ptrace_get_syscall_info_seccomp(struct task_struct *child, struct pt_regs *regs,
+ struct ptrace_syscall_info *info)
+{
+ /*
+ * As struct ptrace_syscall_info.entry is currently a subset
+ * of struct ptrace_syscall_info.seccomp, it makes sense to
+ * initialize that subset using ptrace_get_syscall_info_entry().
+ * This can be reconsidered in the future if these structures
+ * diverge significantly enough.
+ */
+ ptrace_get_syscall_info_entry(child, regs, info);
+ info->op = PTRACE_SYSCALL_INFO_SECCOMP;
+ info->seccomp.ret_data = child->ptrace_message;
+
+ /* ret_data is the last field in struct ptrace_syscall_info.seccomp */
+ return offsetofend(struct ptrace_syscall_info, seccomp.ret_data);
+}
+
+static unsigned long
+ptrace_get_syscall_info_exit(struct task_struct *child, struct pt_regs *regs,
+ struct ptrace_syscall_info *info)
+{
+ info->op = PTRACE_SYSCALL_INFO_EXIT;
+ info->exit.rval = syscall_get_error(child, regs);
+ info->exit.is_error = !!info->exit.rval;
+ if (!info->exit.is_error)
+ info->exit.rval = syscall_get_return_value(child, regs);
+
+ /* is_error is the last field in struct ptrace_syscall_info.exit */
+ return offsetofend(struct ptrace_syscall_info, exit.is_error);
+}
+
+static int
+ptrace_get_syscall_info(struct task_struct *child, unsigned long user_size,
+ void __user *datavp)
+{
+ struct pt_regs *regs = task_pt_regs(child);
+ struct ptrace_syscall_info info = {
+ .op = PTRACE_SYSCALL_INFO_NONE,
+ .arch = syscall_get_arch(child),
+ .instruction_pointer = instruction_pointer(regs),
+ .stack_pointer = user_stack_pointer(regs),
+ };
+ unsigned long actual_size = offsetof(struct ptrace_syscall_info, entry);
+ unsigned long write_size;
+
+ /*
+ * This does not need lock_task_sighand() to access
+ * child->last_siginfo because ptrace_freeze_traced()
+ * called earlier by ptrace_check_attach() ensures that
+ * the tracee cannot go away and clear its last_siginfo.
+ */
+ switch (child->last_siginfo ? child->last_siginfo->si_code : 0) {
+ case SIGTRAP | 0x80:
+ switch (child->ptrace_message) {
+ case PTRACE_EVENTMSG_SYSCALL_ENTRY:
+ actual_size = ptrace_get_syscall_info_entry(child, regs,
+ &info);
+ break;
+ case PTRACE_EVENTMSG_SYSCALL_EXIT:
+ actual_size = ptrace_get_syscall_info_exit(child, regs,
+ &info);
+ break;
+ }
+ break;
+ case SIGTRAP | (PTRACE_EVENT_SECCOMP << 8):
+ actual_size = ptrace_get_syscall_info_seccomp(child, regs,
+ &info);
+ break;
+ }
+
+ write_size = min(actual_size, user_size);
+ return copy_to_user(datavp, &info, write_size) ? -EFAULT : actual_size;
+}
+#endif /* CONFIG_HAVE_ARCH_TRACEHOOK */
int ptrace_request(struct task_struct *child, long request,
unsigned long addr, unsigned long data)
@@ -1114,6 +1209,10 @@ int ptrace_request(struct task_struct *child, long request,
ret = __put_user(kiov.iov_len, &uiov->iov_len);
break;
}
+
+ case PTRACE_GET_SYSCALL_INFO:
+ ret = ptrace_get_syscall_info(child, addr, datavp);
+ break;
#endif
case PTRACE_SECCOMP_GET_FILTER:
diff --git a/kernel/signal.c b/kernel/signal.c
index dabe100d2091..91b789dd6e72 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2951,80 +2951,49 @@ EXPORT_SYMBOL(sigprocmask);
*
* This is useful for syscalls such as ppoll, pselect, io_pgetevents and
* epoll_pwait where a new sigmask is passed from userland for the syscalls.
+ *
+ * Note that it does set_restore_sigmask() in advance, so it must be always
+ * paired with restore_saved_sigmask_unless() before return from syscall.
*/
-int set_user_sigmask(const sigset_t __user *usigmask, sigset_t *set,
- sigset_t *oldset, size_t sigsetsize)
+int set_user_sigmask(const sigset_t __user *umask, size_t sigsetsize)
{
- if (!usigmask)
- return 0;
+ sigset_t kmask;
+ if (!umask)
+ return 0;
if (sigsetsize != sizeof(sigset_t))
return -EINVAL;
- if (copy_from_user(set, usigmask, sizeof(sigset_t)))
+ if (copy_from_user(&kmask, umask, sizeof(sigset_t)))
return -EFAULT;
- *oldset = current->blocked;
- set_current_blocked(set);
+ set_restore_sigmask();
+ current->saved_sigmask = current->blocked;
+ set_current_blocked(&kmask);
return 0;
}
-EXPORT_SYMBOL(set_user_sigmask);
#ifdef CONFIG_COMPAT
-int set_compat_user_sigmask(const compat_sigset_t __user *usigmask,
- sigset_t *set, sigset_t *oldset,
+int set_compat_user_sigmask(const compat_sigset_t __user *umask,
size_t sigsetsize)
{
- if (!usigmask)
- return 0;
+ sigset_t kmask;
+ if (!umask)
+ return 0;
if (sigsetsize != sizeof(compat_sigset_t))
return -EINVAL;
- if (get_compat_sigset(set, usigmask))
+ if (get_compat_sigset(&kmask, umask))
return -EFAULT;
- *oldset = current->blocked;
- set_current_blocked(set);
+ set_restore_sigmask();
+ current->saved_sigmask = current->blocked;
+ set_current_blocked(&kmask);
return 0;
}
-EXPORT_SYMBOL(set_compat_user_sigmask);
#endif
-/*
- * restore_user_sigmask:
- * usigmask: sigmask passed in from userland.
- * sigsaved: saved sigmask when the syscall started and changed the sigmask to
- * usigmask.
- *
- * This is useful for syscalls such as ppoll, pselect, io_pgetevents and
- * epoll_pwait where a new sigmask is passed in from userland for the syscalls.
- */
-void restore_user_sigmask(const void __user *usigmask, sigset_t *sigsaved,
- bool interrupted)
-{
-
- if (!usigmask)
- return;
- /*
- * When signals are pending, do not restore them here.
- * Restoring sigmask here can lead to delivering signals that the above
- * syscalls are intended to block because of the sigmask passed in.
- */
- if (interrupted) {
- current->saved_sigmask = *sigsaved;
- set_restore_sigmask();
- return;
- }
-
- /*
- * This is needed because the fast syscall return path does not restore
- * saved_sigmask when signals are not pending.
- */
- set_current_blocked(sigsaved);
-}
-EXPORT_SYMBOL(restore_user_sigmask);
-
/**
* sys_rt_sigprocmask - change the list of currently blocked signals
* @how: whether to add, remove, or set signals
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 1c1ad1e14f21..43186ccfa139 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -188,17 +188,17 @@ extern int no_unaligned_warning;
* enum sysctl_writes_mode - supported sysctl write modes
*
* @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
- * to be written, and multiple writes on the same sysctl file descriptor
- * will rewrite the sysctl value, regardless of file position. No warning
- * is issued when the initial position is not 0.
+ * to be written, and multiple writes on the same sysctl file descriptor
+ * will rewrite the sysctl value, regardless of file position. No warning
+ * is issued when the initial position is not 0.
* @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
- * not 0.
+ * not 0.
* @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
- * file position 0 and the value must be fully contained in the buffer
- * sent to the write syscall. If dealing with strings respect the file
- * position, but restrict this to the max length of the buffer, anything
- * passed the max lenght will be ignored. Multiple writes will append
- * to the buffer.
+ * file position 0 and the value must be fully contained in the buffer
+ * sent to the write syscall. If dealing with strings respect the file
+ * position, but restrict this to the max length of the buffer, anything
+ * passed the max length will be ignored. Multiple writes will append
+ * to the buffer.
*
* These write modes control how current file position affects the behavior of
* updating sysctl values through the proc interface on each write.