diff options
| author | Matthew Dempsky <matthew@cvs.openbsd.org> | 2011-07-06 05:09:02 +0000 |
|---|---|---|
| committer | Matthew Dempsky <matthew@cvs.openbsd.org> | 2011-07-06 05:09:02 +0000 |
| commit | f3f666a75b35617b422413c23685155bcbd49f33 (patch) | |
| tree | f98cc868b25baf24edb9f92ed9a510dc5a56b1a1 /sys/dev | |
| parent | 7d234422c9c97bd73d581a8badf326e45ba9a2a4 (diff) | |
vndstrategy() should fail if VNF_HAVELABEL isn't set. This simplifies
the logic slightly and makes vnd(4) more like any other disk driver.
To avoid races, this means vndopen() can only set VNF_HAVELABEL if
dk_openmask == 0. Otherwise, it's possible for userspace to open
rvnd0c, call VNDIOCSET, open vnd0a, then while vndreaddisklabel() (via
vndstrategy) is waiting for VOP_READ() to finish, you could issue a
read or write on the still open rvnd0c and have VNF_HAVELABEL set but
the disklabel might be in a weird state.
Note that this makes VNF_HAVELABEL nicely analogous to sd(4)/cd(4)'s
SDEV_MEDIA_LOADED flag, which is handled similarly in
{sd,cd}{open,close,strategy}.
ok dlg@, krw@, deraadt@
Diffstat (limited to 'sys/dev')
| -rw-r--r-- | sys/dev/vnd.c | 33 |
1 files changed, 14 insertions, 19 deletions
diff --git a/sys/dev/vnd.c b/sys/dev/vnd.c index 7f391bc3157..d16cf1aaaef 100644 --- a/sys/dev/vnd.c +++ b/sys/dev/vnd.c @@ -1,4 +1,4 @@ -/* $OpenBSD: vnd.c,v 1.138 2011/07/06 04:49:36 matthew Exp $ */ +/* $OpenBSD: vnd.c,v 1.139 2011/07/06 05:09:01 matthew Exp $ */ /* $NetBSD: vnd.c,v 1.26 1996/03/30 23:06:11 christos Exp $ */ /* @@ -52,13 +52,11 @@ #include <sys/errno.h> #include <sys/buf.h> #include <sys/malloc.h> -#include <sys/pool.h> #include <sys/ioctl.h> #include <sys/disklabel.h> #include <sys/device.h> #include <sys/disk.h> #include <sys/stat.h> -#include <sys/mount.h> #include <sys/vnode.h> #include <sys/file.h> #include <sys/uio.h> @@ -186,13 +184,13 @@ vndopen(dev_t dev, int flags, int mode, struct proc *p) } if ((sc->sc_flags & VNF_INITED) && - (sc->sc_flags & VNF_HAVELABEL) == 0) { + (sc->sc_flags & VNF_HAVELABEL) == 0 && + sc->sc_dk.dk_openmask == 0) { sc->sc_flags |= VNF_HAVELABEL; vndgetdisklabel(dev, sc, sc->sc_dk.dk_label, 0); } part = DISKPART(dev); - error = disk_openpart(&sc->sc_dk, part, mode, (sc->sc_flags & VNF_HAVELABEL) != 0); @@ -250,6 +248,9 @@ vndclose(dev_t dev, int flags, int mode, struct proc *p) disk_closepart(&sc->sc_dk, part, mode); + if (sc->sc_dk.dk_openmask == 0) + sc->sc_flags &= ~VNF_HAVELABEL; + disk_unlock(&sc->sc_dk); return (0); } @@ -268,7 +269,7 @@ vndstrategy(struct buf *bp) DNPRINTF(VDB_FOLLOW, "vndstrategy(%p): unit %d\n", bp, unit); - if ((sc->sc_flags & VNF_INITED) == 0) { + if ((sc->sc_flags & VNF_HAVELABEL) == 0) { bp->b_error = ENXIO; bp->b_flags |= B_ERROR; goto done; @@ -290,21 +291,15 @@ vndstrategy(struct buf *bp) goto done; } - /* If we have a label, do a boundary check. */ - if (sc->sc_flags & VNF_HAVELABEL) { - if (bounds_check_with_label(bp, sc->sc_dk.dk_label) == -1) - goto done; + if (bounds_check_with_label(bp, sc->sc_dk.dk_label) == -1) + goto done; - /* - * bounds_check_with_label() changes bp->b_resid, reset it - */ - bp->b_resid = bp->b_bcount; - } + /* + * bounds_check_with_label() changes bp->b_resid, reset it + */ + bp->b_resid = bp->b_bcount; - if (sc->sc_flags & VNF_HAVELABEL) - sz = howmany(bp->b_bcount, sc->sc_dk.dk_label->d_secsize); - else - sz = howmany(bp->b_bcount, DEV_BSIZE); + sz = howmany(bp->b_bcount, sc->sc_dk.dk_label->d_secsize); part = DISKPART(bp->b_dev); off = DL_SECTOBLK(sc->sc_dk.dk_label, |