From: Roland McGrath <roland@redhat.com>
Date: Thu, 10 Apr 2008 22:38:45 +0000 (-0700)
Subject: asmlinkage_protect sys_io_getevents
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=598af051a79d05b751fe793f1fe09fcf74763e02;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

asmlinkage_protect sys_io_getevents

Use asmlinkage_protect in sys_io_getevents, because GCC for i386 with
CONFIG_FRAME_POINTER=n can decide to clobber an argument word on the
stack, i.e. the user struct pt_regs.  Here the problem is not a tail
call, but just the compiler's use of the stack when it inlines and
optimizes the body of the called function.  This seems to avoid it.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/fs/aio.c b/fs/aio.c
index 6af921940622..60a4cd4d1137 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1790,6 +1790,7 @@ asmlinkage long sys_io_getevents(aio_context_t ctx_id,
 		put_ioctx(ioctx);
 	}
 
+	asmlinkage_protect(5, ret, ctx_id, min_nr, nr, events, timeout);
 	return ret;
 }