m68k selects HAVE_ARCH_SECCOMP_FILTER for all configurations, but the ColdFire and 68000 syscall entry paths only branch to syscall_trace_enter() for TIF_SYSCALL_TRACE. TIF_SECCOMP alone falls through to syscall dispatch, leaving installed filters ineffective. Test the combined TIF_SYSCALL_TRACE and TIF_SECCOMP mask in both paths and route either flag through the existing slow path. Leave the classic MMU syscall entry implementation unchanged. Validated the combined test under QEMU mcf5208evb (ColdFire): filters denying getpid, openat, unlinkat, and reboot each returned -EPERM. A classic-MMU control (q800) denied the filtered getpid syscall both before and after this change. The 68000 path shares the same source-level omission and receives the identical masked test but was not separately emulated. Compile-tested W=1 with CONFIG_SECCOMP_FILTER=y on both m5208evb_defconfig and a custom no-MMU UCSIMM configuration; the latter built arch/m68k/68000/entry.o and vmlinux. Fixes: 6baaade15594 ("m68k: Add kernel seccomp support") Cc: stable@vger.kernel.org # v6.3+ Suggested-by: Andreas Schwab Assisted-by: Claude:claude-opus-4-8 Assisted-by: Codex:gpt-5.6-sol Signed-off-by: Christopher Lusk --- Notes: Changes in v2: - Combine the TRACE/SECCOMP tests into a single masked branch per Andreas Schwab; scoped to the ColdFire/68000 paths, classic MMU unchanged. No in-tree m68k defconfig selects the pure-68000/DragonBall path. Compile-tested W=1 with a custom no-MMU UCSIMM configuration and CONFIG_SECCOMP_FILTER=y; arch/m68k/68000/entry.o and vmlinux both built successfully. The combined gate uses the same flags byte as the classic-MMU entry path. arch/m68k/68000/entry.S | 3 ++- arch/m68k/coldfire/entry.S | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/m68k/68000/entry.S b/arch/m68k/68000/entry.S index c257cc415..0d3cbeded 100644 --- a/arch/m68k/68000/entry.S +++ b/arch/m68k/68000/entry.S @@ -79,7 +79,8 @@ ENTRY(system_call) /* Doing a trace ? */ getthreadinfo - btst #(TIF_SYSCALL_TRACE%8),%a2@(TINFO_FLAGS+(31-TIF_SYSCALL_TRACE)/8) + moveb %a2@(TINFO_FLAGS+2),%d1 + andl #((_TIF_SYSCALL_TRACE + _TIF_SECCOMP) >> 8),%d1 jne do_trace cmpl #NR_syscalls,%d0 jcc badsys diff --git a/arch/m68k/coldfire/entry.S b/arch/m68k/coldfire/entry.S index 4ea08336e..d658abdc5 100644 --- a/arch/m68k/coldfire/entry.S +++ b/arch/m68k/coldfire/entry.S @@ -72,7 +72,8 @@ ENTRY(system_call) movel %d2,%a0 movel %a0@,%a1 /* save top of frame */ movel %sp,%a1@(TASK_THREAD+THREAD_ESP0) - btst #(TIF_SYSCALL_TRACE%8),%a0@(TINFO_FLAGS+(31-TIF_SYSCALL_TRACE)/8) + moveb %a0@(TINFO_FLAGS+2),%d2 + andl #((_TIF_SYSCALL_TRACE + _TIF_SECCOMP) >> 8),%d2 bnes 1f movel %d3,%a0 -- 2.55.0