audit_filter_syscall uses the syscall number to reference into a bitmask (e->rule.mask[word]). Not removing the x32 bit before passing the number to this architecture independent codepath will fail to lookup the proper audit bit. Furthermore it will cause an invalid memory access in the kernel if the out of bound location is not mapped:
BUG: unable to handle kernel paging request at ffff8800e5446630 IP: [<ffffffff810fcdd0>] audit_filter_syscall+0x90/0xf0 Cc: linux-kernel@vger.kernel.org Cc: H. J. Lu <hjl.to...@gmail.com> Signed-off-by: Philipp Kern <pk...@google.com> --- arch/x86/kernel/entry_64.S | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 1e96c36..c9aaf60 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -699,6 +699,9 @@ auditsys: movq %rsi,%rcx /* 4th arg: 2nd syscall arg */ movq %rdi,%rdx /* 3rd arg: 1st syscall arg */ movq %rax,%rsi /* 2nd arg: syscall number */ +#if __SYSCALL_MASK != ~0 + andl $__SYSCALL_MASK,%esi +#endif movl $AUDIT_ARCH_X86_64,%edi /* 1st arg: audit arch */ call __audit_syscall_entry LOAD_ARGS 0 /* reload call-clobbered registers */ -- 1.9.1.423.g4596e3a -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/