[PATCH 4.4 158/268] sh: fix debug trap failure to process signals before return to user

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Rich Felker <dalias@xxxxxxxx>

[ Upstream commit 96a598996f6ac518ac79839ecbb17c91af91f4f7 ]

When responding to a debug trap (breakpoint) in userspace, the
kernel's trap handler raised SIGTRAP but returned from the trap via a
code path that ignored pending signals, resulting in an infinite loop
re-executing the trapping instruction.

Signed-off-by: Rich Felker <dalias@xxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/sh/kernel/entry-common.S |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/sh/kernel/entry-common.S
+++ b/arch/sh/kernel/entry-common.S
@@ -255,7 +255,7 @@ debug_trap:
 	mov.l	@r8, r8
 	jsr	@r8
 	 nop
-	bra	__restore_all
+	bra	ret_from_exception
 	 nop
 	CFI_ENDPROC