5.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Liequan Che <cheliequan@xxxxxxxxxx>
commit b2e382ae12a63560fca35050498e19e760adf8c0 upstream.
Commit 028ddcac477b ("bcache: Remove unnecessary NULL point check in
node allocations") leads a NULL pointer deference in cache_set_flush().
1721 if (!IS_ERR_OR_NULL(c->root))
1722 list_add(&c->root->list, &c->btree_cache);
>From the above code in cache_set_flush(), if previous registration code
fails before allocating c->root, it is possible c->root is NULL as what
it is initialized. __bch_btree_node_alloc() never returns NULL but
c->root is possible to be NULL at above line 1721.
This patch replaces IS_ERR() by IS_ERR_OR_NULL() to fix this.
Fixes: 028ddcac477b ("bcache: Remove unnecessary NULL point check in node allocations")
Signed-off-by: Liequan Che <cheliequan@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Cc: Zheng Wang <zyytlz.wz@xxxxxxx>
Reviewed-by: Mingzhe Zou <mingzhe.zou@xxxxxxxxxxxx>
Signed-off-by: Coly Li <colyli@xxxxxxx>
Link: https://lore.kernel.org/r/20241202115638.28957-1-colyli@xxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/md/bcache/super.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1635,7 +1635,7 @@ static void cache_set_flush(struct closu
if (!IS_ERR_OR_NULL(c->gc_thread))
kthread_stop(c->gc_thread);
- if (!IS_ERR(c->root))
+ if (!IS_ERR_OR_NULL(c->root))
list_add(&c->root->list, &c->btree_cache);
/*
