Check the return value of device_lookup_private against NULL.

Reported-by: syzbot+06561ba90b6e618ce6d0@syzkaller.appspotmail.com
This commit is contained in:
nia 2020-12-26 14:50:50 +00:00
parent d90a6f1029
commit e5ad6630f8

View File

@ -1,4 +1,4 @@
/* $NetBSD: fss.c,v 1.109 2020/02/23 15:46:39 ad Exp $ */
/* $NetBSD: fss.c,v 1.110 2020/12/26 14:50:50 nia Exp $ */
/*-
* Copyright (c) 2003 The NetBSD Foundation, Inc.
@ -36,7 +36,7 @@
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.109 2020/02/23 15:46:39 ad Exp $");
__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.110 2020/12/26 14:50:50 nia Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@ -240,6 +240,9 @@ fss_close(dev_t dev, int flags, int mode, struct lwp *l)
cfdata_t cf;
struct fss_softc *sc = device_lookup_private(&fss_cd, minor(dev));
if (sc == NULL)
return ENXIO;
mflag = (mode == S_IFCHR ? FSS_CDEV_OPEN : FSS_BDEV_OPEN);
error = 0;
@ -283,6 +286,11 @@ fss_strategy(struct buf *bp)
const bool write = ((bp->b_flags & B_READ) != B_READ);
struct fss_softc *sc = device_lookup_private(&fss_cd, minor(bp->b_dev));
if (sc == NULL) {
bp->b_error = ENXIO;
goto done;
}
mutex_enter(&sc->sc_slock);
if (write || sc->sc_state != FSS_ACTIVE) {
@ -303,7 +311,8 @@ fss_strategy(struct buf *bp)
return;
done:
mutex_exit(&sc->sc_slock);
if (sc != NULL)
mutex_exit(&sc->sc_slock);
bp->b_resid = bp->b_bcount;
biodone(bp);
}
@ -333,6 +342,9 @@ fss_ioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
struct fss_get50 *fsg50 = (struct fss_get50 *)data;
#endif
if (sc == NULL)
return ENXIO;
switch (cmd) {
case FSSIOCSET50:
fss = &_fss;