Messages in this thread |  | | | Date | Wed, 15 Sep 2010 11:42:40 -0400 | | From | Jeff Mahoney <> | | Subject | Re: [PATCH] drivers/net/tulip/de4x5.c: prevent reading uninitialized stack memory |
| |
On 09/11/2010 07:46 PM, Dan Rosenberg wrote: > The DE4X5_GET_REG device ioctl allows unprivileged users to read 32 > bytes of uninitialized stack memory, because it copies the > uninitialized "addr" member instead of the intended "lval" member. > This patch takes care of it. > > Signed-off-by: Dan Rosenberg<dan.j.rosenberg@gmail.com>
No. This patch may be considered for correctness, but there's no security issue here.
'tmp' is a union, not a struct. Writes to lval are the same as writes to addr. The length is correctly determined so that only initialized memory is used.
-Jeff
> --- linux-2.6.35.4.orig/drivers/net/tulip/de4x5.c 2010-09-11 > 19:12:27.000000000 -0400 > +++ linux-2.6.35.4/drivers/net/tulip/de4x5.c 2010-09-11 19:17:12.000000000 -0400 > @@ -5474,7 +5474,7 @@ de4x5_ioctl(struct net_device *dev, stru > tmp.lval[6] = inl(DE4X5_STRR); j+=4; > tmp.lval[7] = inl(DE4X5_SIGR); j+=4; > ioc->len = j; > - if (copy_to_user(ioc->data, tmp.addr, ioc->len)) return -EFAULT; > + if (copy_to_user(ioc->data, tmp.lval, ioc->len)) return -EFAULT; > break; > > #define DE4X5_DUMP 0x0f /* Dump the DE4X5 Status */ > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
-- Jeff Mahoney SUSE Labs
|  |