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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-09-04 11:18:17 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-09-04 11:18:17 -0700 |
| commit | 6c51e67b64d169419fb13318035bb442f9176612 (patch) | |
| tree | ae6c64a9d703983f9df5f72e74419de2e388e32b /arch/arm64 | |
| parent | e0a195b5225e1285806622cc146dc5c3312fb392 (diff) | |
| parent | cf7de27ab35172a9240f079477cae3146a182998 (diff) | |
| download | linux-6c51e67b64d169419fb13318035bb442f9176612.tar.bz2 | |
Merge branch 'x86-syscall-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull syscall updates from Ingo Molnar:
"Improve the security of set_fs(): we now check the address limit on a
number of key platforms (x86, arm, arm64) before returning to
user-space - without adding overhead to the typical system call fast
path"
* 'x86-syscall-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
arm64/syscalls: Check address limit on user-mode return
arm/syscalls: Check address limit on user-mode return
x86/syscalls: Check address limit on user-mode return
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/include/asm/thread_info.h | 4 | ||||
| -rw-r--r-- | arch/arm64/include/asm/uaccess.h | 3 | ||||
| -rw-r--r-- | arch/arm64/kernel/signal.c | 5 |
3 files changed, 11 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index 46c3b93cf865..c5ba565544ee 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -86,6 +86,7 @@ struct thread_info { #define TIF_NOTIFY_RESUME 2 /* callback before returning to user */ #define TIF_FOREIGN_FPSTATE 3 /* CPU's FP state is not current's */ #define TIF_UPROBE 4 /* uprobe breakpoint or singlestep */ +#define TIF_FSCHECK 5 /* Check FS is USER_DS on return */ #define TIF_NOHZ 7 #define TIF_SYSCALL_TRACE 8 #define TIF_SYSCALL_AUDIT 9 @@ -107,11 +108,12 @@ struct thread_info { #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) #define _TIF_UPROBE (1 << TIF_UPROBE) +#define _TIF_FSCHECK (1 << TIF_FSCHECK) #define _TIF_32BIT (1 << TIF_32BIT) #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ - _TIF_UPROBE) + _TIF_UPROBE | _TIF_FSCHECK) #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \ diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index fab46a0ea223..a801a48a7972 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -45,6 +45,9 @@ static inline void set_fs(mm_segment_t fs) { current_thread_info()->addr_limit = fs; + /* On user-mode return, check fs is correct */ + set_thread_flag(TIF_FSCHECK); + /* * Enable/disable UAO so that copy_to_user() etc can access * kernel memory with the unprivileged instructions. diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index 089c3747995d..e3e3293d1123 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -29,6 +29,7 @@ #include <linux/string.h> #include <linux/tracehook.h> #include <linux/ratelimit.h> +#include <linux/syscalls.h> #include <asm/debug-monitors.h> #include <asm/elf.h> @@ -749,6 +750,10 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, * Update the trace code with the current status. */ trace_hardirqs_off(); + + /* Check valid user FS if needed */ + addr_limit_user_check(); + do { if (thread_flags & _TIF_NEED_RESCHED) { schedule(); |