m68k: Check syscall_trace_enter() return code

Check return code of syscall_trace_enter(), and skip syscall
if -1. Return code will be left at what had been set by
ptrace or seccomp (in regs->d0).

No regression seen in testing with strace on ARAnyM.

Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20230112035529.13521-2-schmitzmic@gmail.com
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
This commit is contained in:
Michael Schmitz 2023-01-12 16:55:27 +13:00 committed by Geert Uytterhoeven
parent 65a1601609
commit 2ca8a1de44
3 changed files with 7 additions and 0 deletions

View File

@ -45,6 +45,8 @@ do_trace:
jbsr syscall_trace_enter
RESTORE_SWITCH_STACK
addql #4,%sp
addql #1,%d0
jeq ret_from_exception
movel %sp@(PT_OFF_ORIG_D0),%d1
movel #-ENOSYS,%d0
cmpl #NR_syscalls,%d1

View File

@ -90,6 +90,8 @@ ENTRY(system_call)
jbsr syscall_trace_enter
RESTORE_SWITCH_STACK
addql #4,%sp
addql #1,%d0
jeq ret_from_exception
movel %d3,%a0
jbsr %a0@
movel %d0,%sp@(PT_OFF_D0) /* save the return value */

View File

@ -184,9 +184,12 @@ do_trace_entry:
jbsr syscall_trace_enter
RESTORE_SWITCH_STACK
addql #4,%sp
addql #1,%d0 | optimization for cmpil #-1,%d0
jeq ret_from_syscall
movel %sp@(PT_OFF_ORIG_D0),%d0
cmpl #NR_syscalls,%d0
jcs syscall
jra ret_from_syscall
badsys:
movel #-ENOSYS,%sp@(PT_OFF_D0)
jra ret_from_syscall