summaryrefslogtreecommitdiff
path: root/arch/arm64/kernel/signal.c
diff options
context:
space:
mode:
authorThomas Garnier <thgarnie@google.com>2017-09-07 08:30:47 -0700
committerThomas Gleixner <tglx@linutronix.de>2017-09-17 19:45:33 +0200
commita2048e34d4655c06d31400646ae495bbfeb16b27 (patch)
treec56a644d70480eb33d9015b8e47c95b0a46df9d0 /arch/arm64/kernel/signal.c
parente33f8d32677fa4f4f8996ef46748f86aac81ccff (diff)
downloadlwn-a2048e34d4655c06d31400646ae495bbfeb16b27.tar.gz
lwn-a2048e34d4655c06d31400646ae495bbfeb16b27.zip
arm64/syscalls: Move address limit check in loop
A bug was reported on ARM where set_fs might be called after it was checked on the work pending function. ARM64 is not affected by this bug but has a similar construct. In order to avoid any similar problems in the future, the addr_limit_user_check function is moved at the beginning of the loop. Fixes: cf7de27ab351 ("arm64/syscalls: Check address limit on user-mode return") Reported-by: Leonard Crestez <leonard.crestez@nxp.com> Signed-off-by: Thomas Garnier <thgarnie@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Pratyush Anand <panand@redhat.com> Cc: Dave Martin <Dave.Martin@arm.com> Cc: Will Drewry <wad@chromium.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Andy Lutomirski <luto@amacapital.net> Cc: David Howells <dhowells@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-api@vger.kernel.org Cc: Yonghong Song <yhs@fb.com> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1504798247-48833-5-git-send-email-keescook@chromium.org
Diffstat (limited to 'arch/arm64/kernel/signal.c')
-rw-r--r--arch/arm64/kernel/signal.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index c45214f8fb54..0bdc96c61bc0 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -751,10 +751,10 @@ asmlinkage void do_notify_resume(struct pt_regs *regs,
*/
trace_hardirqs_off();
- /* Check valid user FS if needed */
- addr_limit_user_check();
-
do {
+ /* Check valid user FS if needed */
+ addr_limit_user_check();
+
if (thread_flags & _TIF_NEED_RESCHED) {
schedule();
} else {