From 44ac6b829c4e173fdf6df18e6dd86aecf9a3dc99 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Fri, 25 Sep 2020 14:53:08 +0200 Subject: [PATCH] udf: Limit sparing table size Although UDF standard allows it, we don't support sparing table larger than a single block. Check it during mount so that we don't try to access memory beyond end of buffer. Reported-by: syzbot+9991561e714f597095da@syzkaller.appspotmail.com Signed-off-by: Jan Kara --- fs/udf/super.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/udf/super.c b/fs/udf/super.c index 413a50599d1c..faf2017ada11 100644 --- a/fs/udf/super.c +++ b/fs/udf/super.c @@ -1345,6 +1345,12 @@ static int udf_load_sparable_map(struct super_block *sb, (int)spm->numSparingTables); return -EIO; } + if (le32_to_cpu(spm->sizeSparingTable) > sb->s_blocksize) { + udf_err(sb, "error loading logical volume descriptor: " + "Too big sparing table size (%u)\n", + le32_to_cpu(spm->sizeSparingTable)); + return -EIO; + } for (i = 0; i < spm->numSparingTables; i++) { loc = le32_to_cpu(spm->locSparingTable[i]);