5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Coly Li <colyli@xxxxxxx> commit 777967e7e9f6f5f3e153abffb562bffaf4430d26 upstream. In btree_gc_rewrite_node(), pointer 'n' is not checked after it returns from btree_gc_rewrite_node(). There is potential possibility that 'n' is a non NULL ERR_PTR(), referencing such error code is not permitted in following code. Therefore a return value checking is necessary after 'n' is back from btree_node_alloc_replacement(). Signed-off-by: Coly Li <colyli@xxxxxxx> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20231120052503.6122-3-colyli@xxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/bcache/btree.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -1555,6 +1555,8 @@ static int btree_gc_rewrite_node(struct return 0; n = btree_node_alloc_replacement(replace, NULL); + if (IS_ERR(n)) + return 0; /* recheck reserve after allocating replacement node */ if (btree_check_reserve(b, NULL)) {
