From d3316c8233bb05e0dd855d30aac347bb8ad76ee4 Mon Sep 17 00:00:00 2001 From: Nikolay Borisov Date: Wed, 25 Sep 2019 14:03:03 +0300 Subject: [PATCH] btrfs: Properly handle backref_in_log retval This function can return a negative error value if btrfs_search_slot errors for whatever reason or if btrfs_alloc_path runs out of memory. This is currently problemattic because backref_in_log is treated by its callers as if it returns boolean. Fix this by adding proper error handling in callers. That also enables the function to return the direct error code from btrfs_search_slot. Signed-off-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/tree-log.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-) diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 1d7f22951ef2..24fa6560655c 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -952,7 +952,9 @@ static noinline int backref_in_log(struct btrfs_root *log, return -ENOMEM; ret = btrfs_search_slot(NULL, log, key, path, 0, 0); - if (ret != 0) { + if (ret < 0) { + goto out; + } else if (ret == 1) { ret = 0; goto out; } @@ -1026,10 +1028,13 @@ again: (unsigned long)(victim_ref + 1), victim_name_len); - if (!backref_in_log(log_root, &search_key, - parent_objectid, - victim_name, - victim_name_len)) { + ret = backref_in_log(log_root, &search_key, + parent_objectid, victim_name, + victim_name_len); + if (ret < 0) { + kfree(victim_name); + return ret; + } else if (!ret) { inc_nlink(&inode->vfs_inode); btrfs_release_path(path); @@ -1091,10 +1096,12 @@ again: search_key.offset = btrfs_extref_hash(parent_objectid, victim_name, victim_name_len); - ret = 0; - if (!backref_in_log(log_root, &search_key, - parent_objectid, victim_name, - victim_name_len)) { + ret = backref_in_log(log_root, &search_key, + parent_objectid, victim_name, + victim_name_len); + if (ret < 0) { + return ret; + } else if (!ret) { ret = -ENOENT; victim_parent = read_one_inode(root, parent_objectid); @@ -1869,16 +1876,19 @@ static bool name_in_log_ref(struct btrfs_root *log_root, const u64 dirid, const u64 ino) { struct btrfs_key search_key; + int ret; search_key.objectid = ino; search_key.type = BTRFS_INODE_REF_KEY; search_key.offset = dirid; - if (backref_in_log(log_root, &search_key, dirid, name, name_len)) + ret = backref_in_log(log_root, &search_key, dirid, name, name_len); + if (ret == 1) return true; search_key.type = BTRFS_INODE_EXTREF_KEY; search_key.offset = btrfs_extref_hash(dirid, name, name_len); - if (backref_in_log(log_root, &search_key, dirid, name, name_len)) + ret = backref_in_log(log_root, &search_key, dirid, name, name_len); + if (ret == 1) return true; return false;