From 8b44ca2b634527151af07447a8090a5f3a043321 Mon Sep 17 00:00:00 2001 From: Phillip Lougher Date: Wed, 24 Mar 2021 21:37:35 -0700 Subject: [PATCH] squashfs: fix xattr id and id lookup sanity checks The checks for maximum metadata block size is missing SQUASHFS_BLOCK_OFFSET (the two byte length count). Link: https://lkml.kernel.org/r/2069685113.2081245.1614583677427@webmail.123-reg.co.uk Fixes: f37aa4c7366e23f ("squashfs: add more sanity checks in id lookup") Signed-off-by: Phillip Lougher Cc: Sean Nyekjaer Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/squashfs/id.c | 6 ++++-- fs/squashfs/xattr_id.c | 6 ++++-- 2 files changed, 8 insertions(+), 4 deletions(-) diff --git a/fs/squashfs/id.c b/fs/squashfs/id.c index 11581bf31af4..ea5387679723 100644 --- a/fs/squashfs/id.c +++ b/fs/squashfs/id.c @@ -97,14 +97,16 @@ __le64 *squashfs_read_id_index_table(struct super_block *sb, start = le64_to_cpu(table[n]); end = le64_to_cpu(table[n + 1]); - if (start >= end || (end - start) > SQUASHFS_METADATA_SIZE) { + if (start >= end || (end - start) > + (SQUASHFS_METADATA_SIZE + SQUASHFS_BLOCK_OFFSET)) { kfree(table); return ERR_PTR(-EINVAL); } } start = le64_to_cpu(table[indexes - 1]); - if (start >= id_table_start || (id_table_start - start) > SQUASHFS_METADATA_SIZE) { + if (start >= id_table_start || (id_table_start - start) > + (SQUASHFS_METADATA_SIZE + SQUASHFS_BLOCK_OFFSET)) { kfree(table); return ERR_PTR(-EINVAL); } diff --git a/fs/squashfs/xattr_id.c b/fs/squashfs/xattr_id.c index ead66670b41a..087cab8c78f4 100644 --- a/fs/squashfs/xattr_id.c +++ b/fs/squashfs/xattr_id.c @@ -109,14 +109,16 @@ __le64 *squashfs_read_xattr_id_table(struct super_block *sb, u64 table_start, start = le64_to_cpu(table[n]); end = le64_to_cpu(table[n + 1]); - if (start >= end || (end - start) > SQUASHFS_METADATA_SIZE) { + if (start >= end || (end - start) > + (SQUASHFS_METADATA_SIZE + SQUASHFS_BLOCK_OFFSET)) { kfree(table); return ERR_PTR(-EINVAL); } } start = le64_to_cpu(table[indexes - 1]); - if (start >= table_start || (table_start - start) > SQUASHFS_METADATA_SIZE) { + if (start >= table_start || (table_start - start) > + (SQUASHFS_METADATA_SIZE + SQUASHFS_BLOCK_OFFSET)) { kfree(table); return ERR_PTR(-EINVAL); }