From: Michael Schmitz <schmitzmic@xxxxxxxxx> [ Upstream commit 2ca8a1de4437f21562e57f9ac123914747a8e7a1 ] 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@xxxxxxxxx> Reviewed-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230112035529.13521-2-schmitzmic@xxxxxxxxx Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/m68k/68000/entry.S | 2 ++ arch/m68k/coldfire/entry.S | 2 ++ arch/m68k/kernel/entry.S | 3 +++ 3 files changed, 7 insertions(+) diff --git a/arch/m68k/68000/entry.S b/arch/m68k/68000/entry.S index 997b549330156..7d63e2f1555a0 100644 --- a/arch/m68k/68000/entry.S +++ b/arch/m68k/68000/entry.S @@ -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 diff --git a/arch/m68k/coldfire/entry.S b/arch/m68k/coldfire/entry.S index 9f337c70243a3..35104c5417ff4 100644 --- a/arch/m68k/coldfire/entry.S +++ b/arch/m68k/coldfire/entry.S @@ -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 */ diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S index 18f278bdbd218..42879e6eb651d 100644 --- a/arch/m68k/kernel/entry.S +++ b/arch/m68k/kernel/entry.S @@ -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 -- 2.39.0