Commit-ID: a2048e34d4655c06d31400646ae495bbfeb16b27 Gitweb: http://git.kernel.org/tip/a2048e34d4655c06d31400646ae495bbfeb16b27 Author: Thomas Garnier <thgar...@google.com> AuthorDate: Thu, 7 Sep 2017 08:30:47 -0700 Committer: Thomas Gleixner <t...@linutronix.de> CommitDate: Sun, 17 Sep 2017 19:45:33 +0200
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.cres...@nxp.com> Signed-off-by: Thomas Garnier <thgar...@google.com> Signed-off-by: Kees Cook <keesc...@chromium.org> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Cc: Pratyush Anand <pan...@redhat.com> Cc: Dave Martin <dave.mar...@arm.com> Cc: Will Drewry <w...@chromium.org> Cc: Arnd Bergmann <a...@arndb.de> Cc: Catalin Marinas <catalin.mari...@arm.com> Cc: Will Deacon <will.dea...@arm.com> Cc: Russell King <li...@armlinux.org.uk> Cc: Andy Lutomirski <l...@amacapital.net> Cc: David Howells <dhowe...@redhat.com> Cc: Dave Hansen <dave.han...@intel.com> Cc: Al Viro <v...@zeniv.linux.org.uk> Cc: linux-...@vger.kernel.org Cc: Yonghong Song <y...@fb.com> Cc: linux-arm-ker...@lists.infradead.org Link: http://lkml.kernel.org/r/1504798247-48833-5-git-send-email-keesc...@chromium.org --- arch/arm64/kernel/signal.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index c45214f..0bdc96c 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 {