diff options
| author | Kyle Evans <kevans@FreeBSD.org> | 2026-06-30 19:12:10 +0000 |
|---|---|---|
| committer | Kyle Evans <kevans@FreeBSD.org> | 2026-08-06 23:36:14 +0000 |
| commit | 29a68ae63caca205772e570ea6f6045ffb74c912 (patch) | |
| tree | 59e57f68b2498aad211c0c688377c406089561f2 | |
| parent | 240bd2eeb21f959f7340402211c0bf43a58d31b5 (diff) | |
kern: syscall_thread_enter() cannot fail
Attempting to handle the error gracefully can easily result in missing
SIGSYS, so this was made to always succeed in
39024a89146 ("syscalls: fix missing SIGSYS for several ENOSYS errors")
and returns the nosys entry on failure.
Drop the pretense of returning an error and clean up a few dead error
paths.
Reviewed by: kib, markj
(cherry picked from commit eca26803d880060555393ab89b44b967cd467a0e)
| -rw-r--r-- | sys/kern/kern_sig.c | 8 | ||||
| -rw-r--r-- | sys/kern/kern_syscalls.c | 5 | ||||
| -rw-r--r-- | sys/kern/subr_syscall.c | 6 | ||||
| -rw-r--r-- | sys/sys/sysent.h | 2 |
4 files changed, 6 insertions, 15 deletions
diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c index 5f2034525bc0..defba6848409 100644 --- a/sys/kern/kern_sig.c +++ b/sys/kern/kern_sig.c @@ -2690,7 +2690,7 @@ ptrace_syscallreq(struct thread *td, struct proc *p, struct sysent *se; register_t rv_saved[2]; unsigned int sc; - int error, nerror; + int nerror; bool audited, sy_thr_static; sc = tsr->ts_sa.code; @@ -2734,12 +2734,8 @@ ptrace_syscallreq(struct thread *td, struct proc *p, audited = AUDIT_SYSCALL_ENTER(sc, td) != 0; if (!sy_thr_static) { - error = syscall_thread_enter(td, &se); + syscall_thread_enter(td, &se); sy_thr_static = (se->sy_thrcnt & SY_THR_STATIC) != 0; - if (error != 0) { - tsr->ts_ret.sr_error = error; - return; - } } rv_saved[0] = td->td_retval[0]; diff --git a/sys/kern/kern_syscalls.c b/sys/kern/kern_syscalls.c index 7ddc28ed4e26..63572cd13215 100644 --- a/sys/kern/kern_syscalls.c +++ b/sys/kern/kern_syscalls.c @@ -88,7 +88,7 @@ syscall_thread_drain(struct sysent *se) pause("scdrn", hz/2); } -int +void syscall_thread_enter(struct thread *td, struct sysent **se) { uint32_t cnt, oldcnt; @@ -100,11 +100,10 @@ syscall_thread_enter(struct thread *td, struct sysent **se) oldcnt = (*se)->sy_thrcnt; if ((oldcnt & (SY_THR_DRAINING | SY_THR_ABSENT)) != 0) { *se = &nosys_sysent; - return (0); + break; } cnt = oldcnt + SY_THR_INCR; } while (atomic_cmpset_acq_32(&(*se)->sy_thrcnt, oldcnt, cnt) == 0); - return (0); } void diff --git a/sys/kern/subr_syscall.c b/sys/kern/subr_syscall.c index 64fc24d149a6..9997a6b638f7 100644 --- a/sys/kern/subr_syscall.c +++ b/sys/kern/subr_syscall.c @@ -150,12 +150,8 @@ syscallenter(struct thread *td) if (__predict_false(AUDIT_SYSCALL_ENABLED() || SYSTRACE_ENABLED() || !sy_thr_static)) { if (!sy_thr_static) { - error = syscall_thread_enter(td, &se); + syscall_thread_enter(td, &se); sy_thr_static = (se->sy_thrcnt & SY_THR_STATIC) != 0; - if (error != 0) { - td->td_errno = error; - goto retval; - } } #ifdef KDTRACE_HOOKS diff --git a/sys/sys/sysent.h b/sys/sys/sysent.h index 6de391dcc03e..b2a559da7844 100644 --- a/sys/sys/sysent.h +++ b/sys/sys/sysent.h @@ -328,7 +328,7 @@ struct nosys_args; int lkmnosys(struct thread *, struct nosys_args *); int lkmressys(struct thread *, struct nosys_args *); -int syscall_thread_enter(struct thread *td, struct sysent **se); +void syscall_thread_enter(struct thread *td, struct sysent **se); void syscall_thread_exit(struct thread *td, struct sysent *se); int shared_page_alloc(int size, int align); |