bcachefs: Fix use-after-free in bch2_dev_add()

If __bch2_dev_attach_bdev() fails, bch2_dev_free() is called twice.
Once here and another time in the error handling path.

This leads to several use-after-free.

Remove the redundant call and only rely on the error handling path.

Fixes: 6a44735653d4 ("bcachefs: Improved superblock-related error messages")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/super.c b/fs/bcachefs/super.c
index 94e296397e3238a24c73d48a7e54c7e5c096b61f..9f852a6dd76a1134f2796136a9cb8ae152e2bad1 100644 (file)
--- a/fs/bcachefs/super.c
+++ b/fs/bcachefs/super.c
@@ -1613,10 +1613,8 @@ int bch2_dev_add(struct bch_fs *c, const char *path)
        bch2_dev_usage_init(ca);
 
        ret = __bch2_dev_attach_bdev(ca, &sb);
-       if (ret) {
-               bch2_dev_free(ca);
+       if (ret)
                goto err;
-       }
 
        ret = bch2_dev_journal_alloc(ca);
        if (ret) {