From: Phillip Lougher <phillip@squashfs.org.uk> stable inclusion from stable-v5.10.245 commit 2871c74caa3f4f05b429e6bfefebac62dbf1b408 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ID6BW5 CVE: CVE-2025-40200 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=t... -------------------------------- [ Upstream commit 9f1c14c1de1bdde395f6cc893efa4f80a2ae3b2b ] 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. [phillip@squashfs.org.uk: only need to check 64 bit quantity] Link: https://lkml.kernel.org/r/20250926222305.110103-1-phillip@squashfs.org.uk Link: https://lkml.kernel.org/r/20250926215935.107233-1-phillip@squashfs.org.uk Fixes: 6545b246a2c8 ("Squashfs: inode operations") Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk> Reported-by: syzbot+f754e01116421e9754b9@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/68d580e5.a00a0220.303701.0019.GAE@google.com/ Cc: Amir Goldstein <amir73il@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Long Li <leo.lilong@huawei.com> --- fs/squashfs/inode.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/squashfs/inode.c b/fs/squashfs/inode.c index b0a5ce62dae4..42c97c68db63 100644 --- a/fs/squashfs/inode.c +++ b/fs/squashfs/inode.c @@ -193,6 +193,10 @@ 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