git: a015500ef39e - stable/13 - pf syncookies: fix memory leak

The branch stable/13 has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=a015500ef39e9732b342f831e0edbeade850707f

commit a015500ef39e9732b342f831e0edbeade850707f
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2022-04-07 06:41:37 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2022-06-06 07:01:00 +0000

    pf syncookies: fix memory leak
    
    We forgot to free the nvlist (and packed nvlist) on success.
    While here start using the ERROUT macro to clean up error handling, and
    to add SDTs for better debugging.
    
    Reported by:    Coverity
    CID:            1473150
    
    (cherry picked from commit be461cdfb36e229040aafae07a2ba68f73091431)
---
 sys/netpfil/pf/pf_syncookies.c | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/sys/netpfil/pf/pf_syncookies.c b/sys/netpfil/pf/pf_syncookies.c
index 32b2bec6c3d6..5230502be30c 100644
--- a/sys/netpfil/pf/pf_syncookies.c
+++ b/sys/netpfil/pf/pf_syncookies.c
@@ -141,10 +141,13 @@ pf_get_syncookies(struct pfioc_nv *nv)
 {
 	nvlist_t	*nvl = NULL;
 	void		*nvlpacked = NULL;
+	int		 error;
+
+#define ERROUT(x)	ERROUT_FUNCTION(errout, x)
 
 	nvl = nvlist_create(0);
 	if (nvl == NULL)
-		return (ENOMEM);
+		ERROUT(ENOMEM);
 
 	nvlist_add_bool(nvl, "enabled",
 	    V_pf_status.syncookies_mode != PF_SYNCOOKIES_NEVER);
@@ -154,21 +157,23 @@ pf_get_syncookies(struct pfioc_nv *nv)
 	nvlist_add_number(nvl, "lowwater", V_pf_syncookie_status.lowat);
 
 	nvlpacked = nvlist_pack(nvl, &nv->len);
-	if (nvlpacked == NULL) {
-		nvlist_destroy(nvl);
-		return (ENOMEM);
-	}
+	if (nvlpacked == NULL)
+		ERROUT(ENOMEM);
+
 	if (nv->size == 0) {
-		nvlist_destroy(nvl);
-		free(nvlpacked, M_TEMP);
-		return (0);
+		ERROUT(0);
 	} else if (nv->size < nv->len) {
-		nvlist_destroy(nvl);
-		free(nvlpacked, M_TEMP);
-		return (ENOSPC);
+		ERROUT(ENOSPC);
 	}
 
-	return (copyout(nvlpacked, nv->data, nv->len));
+	error = copyout(nvlpacked, nv->data, nv->len);
+
+#undef ERROUT
+errout:
+	nvlist_destroy(nvl);
+	free(nvlpacked, M_TEMP);
+
+	return (error);
 }
 
 int