[src/trunk]: src/sys/dev/i2c Don't panic with invalid user data, just return ...

[mlelstv <mlelstv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/71f586f4d520
branches:  trunk
changeset: 373212:71f586f4d520
user:      mlelstv <mlelstv%NetBSD.org@localhost>
date:      Tue Jan 24 07:09:48 2023 +0000

description:
Don't panic with invalid user data, just return an error.

diffstat:

 sys/dev/i2c/ds1307.c |  7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)

diffs (33 lines):

diff -r 089ae0e557d1 -r 71f586f4d520 sys/dev/i2c/ds1307.c
--- a/sys/dev/i2c/ds1307.c      Tue Jan 24 07:04:27 2023 +0000
+++ b/sys/dev/i2c/ds1307.c      Tue Jan 24 07:09:48 2023 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ds1307.c,v 1.39 2021/08/03 23:12:14 andvar Exp $       */
+/*     $NetBSD: ds1307.c,v 1.40 2023/01/24 07:09:48 mlelstv Exp $      */
 
 /*
  * Copyright (c) 2003 Wasabi Systems, Inc.
@@ -36,7 +36,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ds1307.c,v 1.39 2021/08/03 23:12:14 andvar Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ds1307.c,v 1.40 2023/01/24 07:09:48 mlelstv Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -411,13 +411,12 @@
                return ENXIO;
 
        const struct dsrtc_model * const dm = &sc->sc_model;
-       if (uio->uio_offset >= dm->dm_nvram_size)
+       if (uio->uio_offset < 0 || uio->uio_offset >= dm->dm_nvram_size)
                return EINVAL;
 
        if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0)
                return error;
 
-       KASSERT(uio->uio_offset >= 0);
        while (uio->uio_resid && uio->uio_offset < dm->dm_nvram_size) {
                uint8_t ch, cmd;
                const u_int a = uio->uio_offset;