From 2d11d274e2e1d7c79e2ca8461ce3ff3a95c11171 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Mon, 23 Jun 2025 12:11:58 +0100 Subject: [PATCH] btrfs: fix iteration of extrefs during log replay [ Upstream commit 54a7081ed168b72a8a2d6ef4ba3a1259705a2926 ] At __inode_add_ref() when processing extrefs, if we jump into the next label we have an undefined value of victim_name.len, since we haven't initialized it before we did the goto. This results in an invalid memory access in the next iteration of the loop since victim_name.len was not initialized to the length of the name of the current extref. Fix this by initializing victim_name.len with the current extref's name length. Fixes: e43eec81c516 ("btrfs: use struct qstr instead of name and namelen pairs") Reviewed-by: Johannes Thumshirn Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Signed-off-by: David Sterba Signed-off-by: Sasha Levin --- fs/btrfs/tree-log.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 6dbb62f83f8c..13377c3b2289 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -1162,13 +1162,13 @@ again: struct fscrypt_str victim_name; extref = (struct btrfs_inode_extref *)(base + cur_offset); + victim_name.len = btrfs_inode_extref_name_len(leaf, extref); if (btrfs_inode_extref_parent(leaf, extref) != parent_objectid) goto next; ret = read_alloc_one_name(leaf, &extref->name, - btrfs_inode_extref_name_len(leaf, extref), - &victim_name); + victim_name.len, &victim_name); if (ret) return ret;