From 2dcf838cf5c2f0f4501edaa1680fcad03618d760 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Tue, 3 Jun 2025 19:29:01 +0100 Subject: [PATCH] btrfs: fix invalid inode pointer dereferences during log replay In a few places where we call read_one_inode(), if we get a NULL pointer we end up jumping into an error path, or fallthrough in case of __add_inode_ref(), where we then do something like this: iput(&inode->vfs_inode); which results in an invalid inode pointer that triggers an invalid memory access, resulting in a crash. Fix this by making sure we don't do such dereferences. Fixes: b4c50cbb01a1 ("btrfs: return a btrfs_inode from read_one_inode()") CC: stable@vger.kernel.org # 6.15+ Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/tree-log.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 97e933113b82..21d2f3dded51 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -668,15 +668,12 @@ static noinline int replay_one_extent(struct btrfs_trans_handle *trans, extent_end = ALIGN(start + size, fs_info->sectorsize); } else { - ret = 0; - goto out; + return 0; } inode = read_one_inode(root, key->objectid); - if (!inode) { - ret = -EIO; - goto out; - } + if (!inode) + return -EIO; /* * first check to see if we already have this extent in the @@ -961,7 +958,8 @@ static noinline int drop_one_dir_item(struct btrfs_trans_handle *trans, ret = unlink_inode_for_log_replay(trans, dir, inode, &name); out: kfree(name.name); - iput(&inode->vfs_inode); + if (inode) + iput(&inode->vfs_inode); return ret; } @@ -1176,8 +1174,8 @@ again: ret = unlink_inode_for_log_replay(trans, victim_parent, inode, &victim_name); + iput(&victim_parent->vfs_inode); } - iput(&victim_parent->vfs_inode); kfree(victim_name.name); if (ret) return ret; -- 2.50.1