diff options
author | Andy Lutomirski <luto@kernel.org> | 2018-06-27 08:45:52 +0300 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2018-06-27 10:35:40 +0300 |
commit | 22cd978e598618e82c3c3348d2069184f6884182 (patch) | |
tree | 45ef6fb97a483dce41a4ee7fb614b0bdc0307563 | |
parent | 0e311d237d7f3022b7dafb639b42541bfb42fe94 (diff) | |
download | linux-22cd978e598618e82c3c3348d2069184f6884182.tar.xz |
x86/entry/64/compat: Fix "x86/entry/64/compat: Preserve r8-r11 in int $0x80"
Commit:
8bb2610bc496 ("x86/entry/64/compat: Preserve r8-r11 in int $0x80")
was busted: my original patch had a minor conflict with
some of the nospec changes, but "git apply" is very clever
and silently accepted the patch by making the same changes
to a different function in the same file. There was obviously
a huge offset, but "git apply" for some reason doesn't feel
any need to say so.
Move the changes to the correct function. Now the
test_syscall_vdso_32 selftests passes.
If anyone cares to observe the original problem, try applying the
patch at:
https://lore.kernel.org/lkml/d4c4d9985fbe64f8c9e19291886453914b48caee.1523975710.git.luto@kernel.org/raw
to the kernel at 316d097c4cd4e7f2ef50c40cff2db266593c4ec4:
- "git am" and "git apply" accept the patch without any complaints at all
- "patch -p1" at least prints out a message about the huge offset.
Reported-by: zhijianx.li@intel.com
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 #v4.17+
Fixes: 8bb2610bc496 ("x86/entry/64/compat: Preserve r8-r11 in int $0x80")
Link: http://lkml.kernel.org/r/6012b922485401bc42676e804171ded262fc2ef2.1530078306.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-rw-r--r-- | arch/x86/entry/entry_64_compat.S | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index 9de7f1e1dede..7d0df78db727 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -84,13 +84,13 @@ ENTRY(entry_SYSENTER_compat) pushq %rdx /* pt_regs->dx */ pushq %rcx /* pt_regs->cx */ pushq $-ENOSYS /* pt_regs->ax */ - pushq %r8 /* pt_regs->r8 */ + pushq $0 /* pt_regs->r8 = 0 */ xorl %r8d, %r8d /* nospec r8 */ - pushq %r9 /* pt_regs->r9 */ + pushq $0 /* pt_regs->r9 = 0 */ xorl %r9d, %r9d /* nospec r9 */ - pushq %r10 /* pt_regs->r10 */ + pushq $0 /* pt_regs->r10 = 0 */ xorl %r10d, %r10d /* nospec r10 */ - pushq %r11 /* pt_regs->r11 */ + pushq $0 /* pt_regs->r11 = 0 */ xorl %r11d, %r11d /* nospec r11 */ pushq %rbx /* pt_regs->rbx */ xorl %ebx, %ebx /* nospec rbx */ @@ -374,13 +374,13 @@ ENTRY(entry_INT80_compat) pushq %rcx /* pt_regs->cx */ xorl %ecx, %ecx /* nospec cx */ pushq $-ENOSYS /* pt_regs->ax */ - pushq $0 /* pt_regs->r8 = 0 */ + pushq %r8 /* pt_regs->r8 */ xorl %r8d, %r8d /* nospec r8 */ - pushq $0 /* pt_regs->r9 = 0 */ + pushq %r9 /* pt_regs->r9 */ xorl %r9d, %r9d /* nospec r9 */ - pushq $0 /* pt_regs->r10 = 0 */ + pushq %r10 /* pt_regs->r10*/ xorl %r10d, %r10d /* nospec r10 */ - pushq $0 /* pt_regs->r11 = 0 */ + pushq %r11 /* pt_regs->r11 */ xorl %r11d, %r11d /* nospec r11 */ pushq %rbx /* pt_regs->rbx */ xorl %ebx, %ebx /* nospec rbx */ |