Syskaller reports a "WARNING in ovl_copy_up_file" in overlayfs.
This warning is ultimately caused because the underlying
Squashfs file system returns a file with a negative file size.
This commit checks for a negative file size and returns EINVAL.
Fixes: 6545b246a2c8 ("Squashfs: inode operations")
Reported-by: syzbot+f754e01116421e9754b9@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68d580e5.a00a0220.303701.0019.GAE@google.com/
Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk>
---
V2: only need to check 64 bit quantity
---
fs/squashfs/inode.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/fs/squashfs/inode.c b/fs/squashfs/inode.c
index 5920a33e44a1..49046a286e20 100644
--- a/fs/squashfs/inode.c
+++ b/fs/squashfs/inode.c
@@ -192,6 +192,10 @@ int squashfs_read_inode(struct inode *inode, long long ino)
goto failed_read;
inode->i_size = le64_to_cpu(sqsh_ino->file_size);
+ if (inode->i_size < 0) {
+ err = -EINVAL;
+ goto failed_read;
+ }
frag = le32_to_cpu(sqsh_ino->fragment);
if (frag != SQUASHFS_INVALID_FRAG) {
/*
--
2.39.2