On 07/11/2019 07:08, Amir Goldstein wrote: > On Thu, Nov 7, 2019 at 1:43 AM Colin King <colin.king@xxxxxxxxxxxxx> wrote: >> >> From: Colin Ian King <colin.king@xxxxxxxxxxxxx> >> >> Some file systems such as squashfs do not set the UUID in the >> superblock resulting in a zero'd UUID. In cases were two or more >> of these file systems are overlayed on the lower layer we can hit >> overlay corruption issues because identical zero'd overlayfs UUIDs >> are impossible to differentiate between. This can be fixed by >> creating an overlayfs UUID based on the file system from the >> superblock s_magic and s_dev fields. (This currently seems like >> enough information to be able create a UUID, but the could be >> scope to use other super block fields such as the pointer s_fs_info >> but may need some obfuscation). >> > > The fix is incorrent. uuid stored in xattr needs to have persistent properties. > In the use case that you describe, the origin file handle should simply be > ignored. > > Please test attached patch. Thanks for the patch. Tested, and the error still occurs: [ 163.959633] overlayfs: invalid origin (etc/.pwd.lock, ftype=8000, origin ftype=4000). Colin > > Thanks, > Amir. >
