diff options
| author | Andy Lutomirski <luto@kernel.org> | 2015-10-16 22:42:55 (GMT) |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-10-18 10:11:16 (GMT) |
| commit | 3bd29515d1cad26fa85a1a9b442de8816c1f5c54 (patch) | |
| tree | 89bc78824c420dafce56d7056571fa11384b03b8 /arch/x86/entry | |
| parent | 657c1eea0019e80685a84cbb1919794243a187c9 (diff) | |
| download | linux-3bd29515d1cad26fa85a1a9b442de8816c1f5c54.tar.xz | |
x86/entry/32: Fix FS and GS restore in opportunistic SYSEXIT
We either need to restore them before popping and thus changing
ESP, or we need to adjust the offsets. The former is simpler.
Reported-and-tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 5f310f739b4c x86/entry/32: ("Re-implement SYSENTER using the new C path")
Link: http://lkml.kernel.org/r/461e5c7d8fa3821529893a4893ac9c4bc37f9e17.1445035014.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/entry')
| -rw-r--r-- | arch/x86/entry/entry_32.S | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index 4f97f49..3eb572e 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -315,14 +315,14 @@ sysenter_past_esp: TRACE_IRQS_ON /* User mode traces as IRQs on. */ movl PT_EIP(%esp), %edx /* pt_regs->ip */ movl PT_OLDESP(%esp), %ecx /* pt_regs->sp */ +1: mov PT_FS(%esp), %fs + PTGS_TO_GS popl %ebx /* pt_regs->bx */ addl $2*4, %esp /* skip pt_regs->cx and pt_regs->dx */ popl %esi /* pt_regs->si */ popl %edi /* pt_regs->di */ popl %ebp /* pt_regs->bp */ popl %eax /* pt_regs->ax */ -1: mov PT_FS(%esp), %fs - PTGS_TO_GS /* * Return back to the vDSO, which will pop ecx and edx. |