The branch main has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=1319c433f4e5d67f8ea6fd2369c604069f733c94
commit 1319c433f4e5d67f8ea6fd2369c604069f733c94 Author: Konstantin Belousov <[email protected]> AuthorDate: 2021-12-28 13:41:30 +0000 Commit: Konstantin Belousov <[email protected]> CommitDate: 2022-01-08 03:41:44 +0000 msdosfs: handle a case when non-dot lookup returned dvp This means that filesystem is corrupted, there is a loop. In collaboration with: pho Reviewed by: markj, mckusick Sponsored by: The FreeBSD Foundation MFC after: 1 week Differential revision: https://reviews.freebsd.org/D33721 --- sys/fs/msdosfs/msdosfs_lookup.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/sys/fs/msdosfs/msdosfs_lookup.c b/sys/fs/msdosfs/msdosfs_lookup.c index d9b52539e602..38bded459692 100644 --- a/sys/fs/msdosfs/msdosfs_lookup.c +++ b/sys/fs/msdosfs/msdosfs_lookup.c @@ -573,6 +573,10 @@ foundroot: goto restart; } } else if (dp->de_StartCluster == scn && isadir) { + if (cnp->cn_namelen != 1 || cnp->cn_nameptr[0] != '.') { + /* fs is corrupted, non-dot lookup returned dvp */ + return (EBADF); + } VREF(vdp); /* we want ourself, ie "." */ *vpp = vdp; } else {
