From ea22982aa6cb0a6503df6b1023a6823adbe22dab Mon Sep 17 00:00:00 2001
From: Sean Nyekjaer <sean@geanix.com>
Date: Thu, 18 Mar 2021 17:01:21 +1100
Subject: [PATCH 1/2] squashfs: fix inode lookup sanity checks
References: bsc#1183750
Git-commit: c1b2028315c6b15e8d6725e0d5884b15887d3daa
Patch-mainline: v5.12-rc5
When mouting a squashfs image created without inode compression it fails
with: "unable to read inode lookup table"
It turns out that the BLOCK_OFFSET is missing when checking the
SQUASHFS_METADATA_SIZE agaist the actual size.
Link: https://lkml.kernel.org/r/20210226092903.1473545-1-sean@geanix.com
Fixes: eabac19e40c0 ("squashfs: add more sanity checks in inode lookup")
Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Acked-by: Phillip Lougher <phillip@squashfs.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Varad Gautam <varad.gautam@suse.com>
---
fs/squashfs/export.c | 8 ++++++--
fs/squashfs/squashfs_fs.h | 1 +
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/fs/squashfs/export.c b/fs/squashfs/export.c
index eb02072d28dd..723763746238 100644
--- a/fs/squashfs/export.c
+++ b/fs/squashfs/export.c
@@ -152,14 +152,18 @@ __le64 *squashfs_read_inode_lookup_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 >= lookup_table_start || (lookup_table_start - start) > SQUASHFS_METADATA_SIZE) {
+ if (start >= lookup_table_start ||
+ (lookup_table_start - start) >
+ (SQUASHFS_METADATA_SIZE + SQUASHFS_BLOCK_OFFSET)) {
kfree(table);
return ERR_PTR(-EINVAL);
}
diff --git a/fs/squashfs/squashfs_fs.h b/fs/squashfs/squashfs_fs.h
index 8d64edb80ebf..b3fdc8212c5f 100644
--- a/fs/squashfs/squashfs_fs.h
+++ b/fs/squashfs/squashfs_fs.h
@@ -17,6 +17,7 @@
/* size of metadata (inode and directory) blocks */
#define SQUASHFS_METADATA_SIZE 8192
+#define SQUASHFS_BLOCK_OFFSET 2
/* default size of block device I/O */
#ifdef CONFIG_SQUASHFS_4K_DEVBLK_SIZE
--
2.30.2