From f311ade3a7adf31658ed882aaab9f9879fdccef7 Mon Sep 17 00:00:00 2001 From: Wenwen Wang Date: Sat, 1 Feb 2020 20:38:38 +0000 Subject: btrfs: ref-verify: fix memory leaks In btrfs_ref_tree_mod(), 'ref' and 'ra' are allocated through kzalloc() and kmalloc(), respectively. 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, 'ref' and 'ra' are not deallocated, leading to memory leaks. For example, if 'action' is BTRFS_ADD_DELAYED_EXTENT, add_block_entry() will be invoked. If the return value indicates an error, the execution will be redirected to 'out'. But, 'ref' is not deallocated on this path, causing a memory leak. To fix the above issues, deallocate both 'ref' and 'ra' before exiting from the function when an error is encountered. CC: stable@vger.kernel.org # 4.15+ Signed-off-by: Wenwen Wang Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/ref-verify.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs/btrfs/ref-verify.c') diff --git a/fs/btrfs/ref-verify.c b/fs/btrfs/ref-verify.c index b57f3618e58e..454a1015d026 100644 --- a/fs/btrfs/ref-verify.c +++ b/fs/btrfs/ref-verify.c @@ -744,6 +744,7 @@ int btrfs_ref_tree_mod(struct btrfs_fs_info *fs_info, */ be = add_block_entry(fs_info, bytenr, num_bytes, ref_root); if (IS_ERR(be)) { + kfree(ref); kfree(ra); ret = PTR_ERR(be); goto out; @@ -757,6 +758,8 @@ int btrfs_ref_tree_mod(struct btrfs_fs_info *fs_info, "re-allocated a block that still has references to it!"); dump_block_entry(fs_info, be); dump_ref_action(fs_info, ra); + kfree(ref); + kfree(ra); goto out_unlock; } @@ -819,6 +822,7 @@ int btrfs_ref_tree_mod(struct btrfs_fs_info *fs_info, "dropping a ref for a existing root that doesn't have a ref on the block"); dump_block_entry(fs_info, be); dump_ref_action(fs_info, ra); + kfree(ref); kfree(ra); goto out_unlock; } @@ -834,6 +838,7 @@ int btrfs_ref_tree_mod(struct btrfs_fs_info *fs_info, "attempting to add another ref for an existing ref on a tree block"); dump_block_entry(fs_info, be); dump_ref_action(fs_info, ra); + kfree(ref); kfree(ra); goto out_unlock; } -- cgit v1.2.3