From 88287582f4d2dec54f934f3ab39cead5d880e6c2 Mon Sep 17 00:00:00 2001 From: Bragatheswaran Manickavel Date: Sat, 18 Nov 2023 14:40:12 +0530 Subject: [PATCH] btrfs: ref-verify: fix memory leaks in btrfs_ref_tree_mod() commit f91192cd68591c6b037da345bc9fcd5e50540358 upstream. In btrfs_ref_tree_mod(), when !parent 're' was allocated through kmalloc(). In the following code, if an error occurs, the execution will be redirected to 'out' or 'out_unlock' and the function will be exited. However, on some of the paths, 're' are not deallocated and may lead to memory leaks. For example: lookup_block_entry() for 'be' returns NULL, the out label will be invoked. During that flow ref and 'ra' are freed but not 're', which can potentially lead to a memory leak. CC: stable@vger.kernel.org # 5.10+ Reported-and-tested-by: syzbot+d66de4cbf532749df35f@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d66de4cbf532749df35f Signed-off-by: Bragatheswaran Manickavel Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/ref-verify.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/btrfs/ref-verify.c b/fs/btrfs/ref-verify.c index 95d2849..e646662 100644 --- a/fs/btrfs/ref-verify.c +++ b/fs/btrfs/ref-verify.c @@ -791,6 +791,7 @@ int btrfs_ref_tree_mod(struct btrfs_fs_info *fs_info, dump_ref_action(fs_info, ra); kfree(ref); kfree(ra); + kfree(re); goto out_unlock; } else if (be->num_refs == 0) { btrfs_err(fs_info, @@ -800,6 +801,7 @@ int btrfs_ref_tree_mod(struct btrfs_fs_info *fs_info, dump_ref_action(fs_info, ra); kfree(ref); kfree(ra); + kfree(re); goto out_unlock; } -- 2.7.4