From: Luís Henriques <lhenriques@xxxxxxx> commit 26d75a16af285a70863ba6a81f85d81e7e65da50 upstream. If a block is out of range in ext4_get_branch(), -ENOMEM will be returned to user-space. Obviously, this error code isn't really useful. This patch fixes it by making sure the right error code (-EFSCORRUPTED) is propagated to user-space. EUCLEAN is more informative than ENOMEM. Signed-off-by: Luís Henriques <lhenriques@xxxxxxx> Link: https://lore.kernel.org/r/20221109181445.17843-1-lhenriques@xxxxxxx Signed-off-by: Theodore Ts'o <tytso@xxxxxxx> Cc: stable@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/ext4/indirect.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/fs/ext4/indirect.c +++ b/fs/ext4/indirect.c @@ -148,6 +148,7 @@ static Indirect *ext4_get_branch(struct struct super_block *sb = inode->i_sb; Indirect *p = chain; struct buffer_head *bh; + unsigned int key; int ret = -EIO; *err = 0; @@ -156,7 +157,13 @@ static Indirect *ext4_get_branch(struct if (!p->key) goto no_block; while (--depth) { - bh = sb_getblk(sb, le32_to_cpu(p->key)); + key = le32_to_cpu(p->key); + if (key > ext4_blocks_count(EXT4_SB(sb)->s_es)) { + /* the block was out of range */ + ret = -EFSCORRUPTED; + goto failure; + } + bh = sb_getblk(sb, key); if (unlikely(!bh)) { ret = -ENOMEM; goto failure;
