diff options
| author | Roland McGrath <roland@redhat.com> | 2009-02-06 18:15:18 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-03-16 17:52:59 -0700 |
| commit | 045b298368752a4eec3c8d8a754b6fa39a371a22 (patch) | |
| tree | 3d47413545587c1f35b6f210972cd5a83091f281 /arch | |
| parent | 69cb3cbb14ebd32513ab091307384e4e7fc62d72 (diff) | |
x86-64: fix int $0x80 -ENOSYS return
commit c09249f8d1b84344eca882547afdbffee8c09d14 upstream.
One of my past fixes to this code introduced a different new bug.
When using 32-bit "int $0x80" entry for a bogus syscall number,
the return value is not correctly set to -ENOSYS. This only happens
when neither syscall-audit nor syscall tracing is enabled (i.e., never
seen if auditd ever started). Test program:
/* gcc -o int80-badsys -m32 -g int80-badsys.c
Run on x86-64 kernel.
Note to reproduce the bug you need auditd never to have started. */
#include <errno.h>
#include <stdio.h>
int
main (void)
{
long res;
asm ("int $0x80" : "=a" (res) : "0" (99999));
printf ("bad syscall returns %ld\n", res);
return res != -ENOSYS;
}
The fix makes the int $0x80 path match the sysenter and syscall paths.
Reported-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/ia32/ia32entry.S | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S index ffc1bb4fed7d..5e65290e84a0 100644 --- a/arch/x86/ia32/ia32entry.S +++ b/arch/x86/ia32/ia32entry.S @@ -424,9 +424,9 @@ ENTRY(ia32_syscall) orl $TS_COMPAT,TI_status(%r10) testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%r10) jnz ia32_tracesys -ia32_do_syscall: cmpl $(IA32_NR_syscalls-1),%eax - ja int_ret_from_sys_call /* ia32_tracesys has set RAX(%rsp) */ + ja ia32_badsys +ia32_do_call: IA32_ARG_FIXUP call *ia32_sys_call_table(,%rax,8) # xxx: rip relative ia32_sysret: @@ -441,7 +441,9 @@ ia32_tracesys: call syscall_trace_enter LOAD_ARGS32 ARGOFFSET /* reload args from stack in case ptrace changed it */ RESTORE_REST - jmp ia32_do_syscall + cmpl $(IA32_NR_syscalls-1),%eax + ja int_ret_from_sys_call /* ia32_tracesys has set RAX(%rsp) */ + jmp ia32_do_call END(ia32_syscall) ia32_badsys: |