4.9-stable review patch. If anyone has any objections, please let me know.
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From: Andy Lutomirski luto@kernel.org
commit b5069782453459f6ec1fdeb495d9901a4545fcb5 upstream.
POPF would trap if VIP was set regardless of whether IF was set. Fix it.
Suggested-by: Stas Sergeev stsp@list.ru Reported-by: Bart Oldeman bartoldeman@gmail.com Signed-off-by: Andy Lutomirski luto@kernel.org 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: Josh Poimboeuf jpoimboe@redhat.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: stable@vger.kernel.org Fixes: 5ed92a8ab71f ("x86/vm86: Use the normal pt_regs area for vm86") Link: http://lkml.kernel.org/r/ce95f40556e7b2178b6bc06ee9557827ff94bd28.1521003603... Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/x86/kernel/vm86_32.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/arch/x86/kernel/vm86_32.c +++ b/arch/x86/kernel/vm86_32.c @@ -719,7 +719,8 @@ void handle_vm86_fault(struct kernel_vm8 return;
check_vip: - if (VEFLAGS & X86_EFLAGS_VIP) { + if ((VEFLAGS & (X86_EFLAGS_VIP | X86_EFLAGS_VIF)) == + (X86_EFLAGS_VIP | X86_EFLAGS_VIF)) { save_v86_state(regs, VM86_STI); return; }