x86/entry/32: Fix IRET exception

As reported by Lai, the commit 3c88c692c2 ("x86/stackframe/32:
Provide consistent pt_regs") wrecked the IRET EXTABLE entry by making
.Lirq_return not point at IRET.

Fix this by placing IRET_FRAME in RESTORE_REGS, to mirror how
FIXUP_FRAME is part of SAVE_ALL.

Fixes: 3c88c692c2 ("x86/stackframe/32: Provide consistent pt_regs")
Reported-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: stable@kernel.org
This commit is contained in:
Peter Zijlstra 2019-11-20 13:05:06 +01:00
parent 880a98c339
commit 40ad219958

View file

@ -357,6 +357,7 @@
2: popl %es
3: popl %fs
POP_GS \pop
IRET_FRAME
.pushsection .fixup, "ax"
4: movl $0, (%esp)
jmp 1b
@ -1075,7 +1076,6 @@ restore_all:
/* Restore user state */
RESTORE_REGS pop=4 # skip orig_eax/error_code
.Lirq_return:
IRET_FRAME
/*
* ARCH_HAS_MEMBARRIER_SYNC_CORE rely on IRET core serialization
* when returning from IPI handler and when returning from