The branch releng/15.0 has been updated by cperciva: URL: https://cgit.FreeBSD.org/src/commit/?id=88c5a4996b90fb70e5990169170a4e93d19aff23
commit 88c5a4996b90fb70e5990169170a4e93d19aff23 Author: Lexi Winter <[email protected]> AuthorDate: 2025-11-04 00:53:25 +0000 Commit: Colin Percival <[email protected]> CommitDate: 2025-11-05 19:36:12 +0000 ifconfig: Fix invalid free() in ifbridge parse_vlans() does 's = strdup(str)', then calls strsep(&s, ...), then attempts to free(s) at the end of the function. For the success case, this is fine (s is NULL, so it's a trivial memory leak), but in the error case, we will attempt to free an invalid pointer. Fix this by storing the original return value from strdup() and freeing that instead. Approved by: re (cperciva) MFC after: 3 seconds Reported by: David Gwynne <[email protected]> Reviewed by: zlei, kevans Sponsored by: https://www.patreon.com/bsdivy Differential Revision: https://reviews.freebsd.org/D53545 (cherry picked from commit 0899f7a3b791ed4878e7cb3859636ec980c76832) (cherry picked from commit fe2e534433778c038138510ff6a8f07066e72703) --- sbin/ifconfig/ifbridge.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/sbin/ifconfig/ifbridge.c b/sbin/ifconfig/ifbridge.c index eff443447c13..8bcf4a638adf 100644 --- a/sbin/ifconfig/ifbridge.c +++ b/sbin/ifconfig/ifbridge.c @@ -811,7 +811,7 @@ unsetbridge_private(if_ctx *ctx, const char *val, int dummy __unused) static int parse_vlans(ifbvlan_set_t *set, const char *str) { - char *s, *token; + char *s, *free_s, *token; /* "none" means the empty vlan set */ if (strcmp(str, "none") == 0) { @@ -829,6 +829,8 @@ parse_vlans(ifbvlan_set_t *set, const char *str) if ((s = strdup(str)) == NULL) return (-1); + /* Keep the original value of s, since strsep() will modify it */ + free_s = s; while ((token = strsep(&s, ",")) != NULL) { unsigned long first, last; @@ -856,11 +858,11 @@ parse_vlans(ifbvlan_set_t *set, const char *str) BRVLAN_SET(set, vlan); } - free(s); + free(free_s); return (0); err: - free(s); + free(free_s); return (-1); }
