From: Tuo Li Date: Sat, 20 Dec 2025 18:11:49 +0000 (+0800) Subject: libceph: make free_choose_arg_map() resilient to partial allocation X-Git-Tag: v6.19-rc5~18^2~3 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e3fe30e57649c551757a02e1cad073c47e1e075e;p=thirdparty%2Flinux.git libceph: make free_choose_arg_map() resilient to partial allocation free_choose_arg_map() may dereference a NULL pointer if its caller fails after a partial allocation. For example, in decode_choose_args(), if allocation of arg_map->args fails, execution jumps to the fail label and free_choose_arg_map() is called. Since arg_map->size is updated to a non-zero value before memory allocation, free_choose_arg_map() will iterate over arg_map->args and dereference a NULL pointer. To prevent this potential NULL pointer dereference and make free_choose_arg_map() more resilient, add checks for pointers before iterating. Cc: stable@vger.kernel.org Co-authored-by: Ilya Dryomov Signed-off-by: Tuo Li Reviewed-by: Viacheslav Dubeyko Signed-off-by: Ilya Dryomov --- diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c index 3377a22e3f6c..92a44026de29 100644 --- a/net/ceph/osdmap.c +++ b/net/ceph/osdmap.c @@ -241,22 +241,26 @@ static struct crush_choose_arg_map *alloc_choose_arg_map(void) static void free_choose_arg_map(struct crush_choose_arg_map *arg_map) { - if (arg_map) { - int i, j; + int i, j; + + if (!arg_map) + return; - WARN_ON(!RB_EMPTY_NODE(&arg_map->node)); + WARN_ON(!RB_EMPTY_NODE(&arg_map->node)); + if (arg_map->args) { for (i = 0; i < arg_map->size; i++) { struct crush_choose_arg *arg = &arg_map->args[i]; - - for (j = 0; j < arg->weight_set_size; j++) - kfree(arg->weight_set[j].weights); - kfree(arg->weight_set); + if (arg->weight_set) { + for (j = 0; j < arg->weight_set_size; j++) + kfree(arg->weight_set[j].weights); + kfree(arg->weight_set); + } kfree(arg->ids); } kfree(arg_map->args); - kfree(arg_map); } + kfree(arg_map); } DEFINE_RB_FUNCS(choose_arg_map, struct crush_choose_arg_map, choose_args_index,