Acquire Giant around calls to kern_sigaction() in sigaction(),

freebsd4_sigaction() and osigaction() instead of around the whole
body of those functions. They now no longer hold Giant around calls
to copyin() and copyout(), and it is slightly more obvious what
Giant is protecting.

1 files changed, 9 insertions, 17 deletions

diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index 9950449..9ca2ff4 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -389,7 +389,6 @@ struct sigaction_args {
 /*
  * MPSAFE
  */
-/* ARGSUSED */
 int
 sigaction(td, uap)
 	struct thread *td;
@@ -399,21 +398,19 @@ sigaction(td, uap)
 	register struct sigaction *actp, *oactp;
 	int error;
 
-	mtx_lock(&Giant);
-
 	actp = (uap->act != NULL) ? &act : NULL;
 	oactp = (uap->oact != NULL) ? &oact : NULL;
 	if (actp) {
 		error = copyin(uap->act, actp, sizeof(act));
 		if (error)
-			goto done2;
+			return (error);
 	}
+	mtx_lock(&Giant);
 	error = kern_sigaction(td, uap->sig, actp, oactp, 0);
+	mtx_unlock(&Giant);
 	if (oactp && !error) {
 		error = copyout(oactp, uap->oact, sizeof(oact));
 	}
-done2:
-	mtx_unlock(&Giant);
 	return (error);
 }
 
@@ -428,7 +425,6 @@ struct freebsd4_sigaction_args {
 /*
  * MPSAFE
  */
-/* ARGSUSED */
 int
 freebsd4_sigaction(td, uap)
 	struct thread *td;
@@ -438,21 +434,20 @@ freebsd4_sigaction(td, uap)
 	register struct sigaction *actp, *oactp;
 	int error;
 
-	mtx_lock(&Giant);
 
 	actp = (uap->act != NULL) ? &act : NULL;
 	oactp = (uap->oact != NULL) ? &oact : NULL;
 	if (actp) {
 		error = copyin(uap->act, actp, sizeof(act));
 		if (error)
-			goto done2;
+			return (error);
 	}
+	mtx_lock(&Giant);
 	error = kern_sigaction(td, uap->sig, actp, oactp, KSA_FREEBSD4);
+	mtx_unlock(&Giant);
 	if (oactp && !error) {
 		error = copyout(oactp, uap->oact, sizeof(oact));
 	}
-done2:
-	mtx_unlock(&Giant);
 	return (error);
 }
 #endif	/* COMAPT_FREEBSD4 */
@@ -468,7 +463,6 @@ struct osigaction_args {
 /*
  * MPSAFE
  */
-/* ARGSUSED */
 int
 osigaction(td, uap)
 	struct thread *td;
@@ -485,25 +479,23 @@ osigaction(td, uap)
 	nsap = (uap->nsa != NULL) ? &nsa : NULL;
 	osap = (uap->osa != NULL) ? &osa : NULL;
 
-	mtx_lock(&Giant);
-
 	if (nsap) {
 		error = copyin(uap->nsa, &sa, sizeof(sa));
 		if (error)
-			goto done2;
+			return (error);
 		nsap->sa_handler = sa.sa_handler;
 		nsap->sa_flags = sa.sa_flags;
 		OSIG2SIG(sa.sa_mask, nsap->sa_mask);
 	}
+	mtx_lock(&Giant);
 	error = kern_sigaction(td, uap->signum, nsap, osap, KSA_OSIGSET);
+	mtx_unlock(&Giant);
 	if (osap && !error) {
 		sa.sa_handler = osap->sa_handler;
 		sa.sa_flags = osap->sa_flags;
 		SIG2OSIG(osap->sa_mask, sa.sa_mask);
 		error = copyout(&sa, uap->osa, sizeof(sa));
 	}
-done2:
-	mtx_unlock(&Giant);
 	return (error);
 }