diff options
| -rw-r--r-- | sys/dev/md/md.c | 24 |
1 files changed, 16 insertions, 8 deletions
diff --git a/sys/dev/md/md.c b/sys/dev/md/md.c index 47aa751..6c3484e 100644 --- a/sys/dev/md/md.c +++ b/sys/dev/md/md.c @@ -909,18 +909,26 @@ mdcreate_vnode(struct md_s *sc, struct md_ioctl *mdio, struct thread *td) { struct vattr vattr; struct nameidata nd; + char *fname; int error, flags, vfslocked; - error = copyinstr(mdio->md_file, sc->file, sizeof(sc->file), NULL); - if (error != 0) - return (error); - flags = FREAD|FWRITE; /* - * If the user specified that this is a read only device, unset the - * FWRITE mask before trying to open the backing store. + * Kernel-originated requests must have the filename appended + * to the mdio structure to protect against malicious software. + */ + fname = mdio->md_file; + if ((void *)fname != (void *)(mdio + 1)) { + error = copyinstr(fname, sc->file, sizeof(sc->file), NULL); + if (error != 0) + return (error); + } else + strlcpy(sc->file, fname, sizeof(sc->file)); + + /* + * If the user specified that this is a read only device, don't + * set the FWRITE mask before trying to open the backing store. */ - if ((mdio->md_options & MD_READONLY) != 0) - flags &= ~FWRITE; + flags = FREAD | ((mdio->md_options & MD_READONLY) ? 0 : FWRITE); NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, sc->file, td); error = vn_open(&nd, &flags, 0, NULL); if (error != 0) |
