Commit e02d48ea authored Jul 05, 2019 by Colin Ian King Committed by David Sterba Jul 05, 2019

btrfs: fix memory leak of path on error return path



Currently if the allocation of roots or tmp_ulist fails the error handling
does not free up the allocation of path causing a memory leak. Fix this and
other similar leaks by moving the call of btrfs_free_path from label out
to label out_free_ulist.

Kudos to David Sterba for spotting the issue in my original fix and suggesting
the correct way to fix the leak and Anand Jain for spotting a double free
issue.

Addresses-Coverity: ("Resource leak")
Fixes: 5911c8fe ("btrfs: fiemap: preallocate ulists for btrfs_check_shared")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

parent 28a32d2b

fs/btrfs/extent_io.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -4611,7 +4611,6 @@ int extent_fiemap(struct inode inode, struct fiemap_extent_info fieinfo,
		ret = btrfs_lookup_file_extent(NULL, root, path,
		btrfs_ino(BTRFS_I(inode)), -1, 0);
		if (ret < 0) {
		btrfs_free_path(path);
		goto out_free_ulist;
		} else {
		WARN_ON(!ret);
		@@ -4764,11 +4763,11 @@ out_free:
		ret = emit_last_fiemap_cache(fieinfo, &cache);
		free_extent_map(em);
		out:
		btrfs_free_path(path);
		unlock_extent_cached(&BTRFS_I(inode)->io_tree, start, start + len - 1,
		&cached_state);

		out_free_ulist:
		btrfs_free_path(path);
		ulist_free(roots);
		ulist_free(tmp_ulist);
		return ret;

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