When uci_set is called with ptr->o set and ptr->option = NULL,
then in uci_expand_ptr ptr->option is set to ptr->o->e.name.
This will result in use-after-free because ptr->option is used in
the call to uci_add_delta after uci_free_option(ptr->o).
Signed-off-by: Jan Venekamp <j...@venekamp.net>
---
list.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/list.c b/list.c
index 24ed2ee..ac3686c 100644
--- a/list.c
+++ b/list.c
@@ -725,15 +725,16 @@ int uci_set(struct uci_context *ctx, struct uci_ptr *ptr)
ptr->s = uci_alloc_section(ptr->p, ptr->value, ptr->section);
ptr->last = &ptr->s->e;
} else if (ptr->o && ptr->option) { /* update option */
- struct uci_option *o;
+ struct uci_option *old = ptr->o;
if ((ptr->o->type == UCI_TYPE_STRING) &&
!strcmp(ptr->o->v.string, ptr->value))
return 0;
- o = ptr->o;
ptr->o = uci_alloc_option(ptr->s, ptr->option, ptr->value);
- uci_free_option(o);
+ if (ptr->option == old->e.name)
+ ptr->option = ptr->o->e.name;
+ uci_free_option(old);
ptr->last = &ptr->o->e;
} else if (ptr->s && ptr->section) { /* update section */
char *s = uci_strdup(ctx, ptr->value);
--
2.32.0 (Apple Git-132)
_______________________________________________
openwrt-devel mailing list
openwrt-devel@lists.openwrt.org
https://lists.openwrt.org/mailman/listinfo/openwrt-devel
