Messages in this thread Patch in this message | | | From | Kevin Corry <> | Subject | Re: [PATCH 3/8] dm: prevent possible buffer overflow in ioctl interface | Date | Fri, 28 Feb 2003 08:59:25 -0600 |
| |
On Friday 28 February 2003 08:32, you wrote: > On Thu, 2003-02-27 at 14:05, Kevin Corry wrote: > > Unfortunately, Linus seems to have committed that patch already. So here > > is a patch to fix just that line. > > > > Thanks for catching that. > > Third time, strlen isn't necessary, it can be done at compile time. > > --- a/drivers/md/dm-ioctl.c 2003/02/27 16:29:58 > +++ b/drivers/md/dm-ioctl.c 2003/02/27 17:21:54 > @@ -174,7 +174,7 @@ > static int register_with_devfs(struct hash_cell *hc) > { > struct gendisk *disk = dm_disk(hc->md); > - char *name = kmalloc(DM_NAME_LEN + strlen(DM_DIR) + 1); > + char *name = kmalloc(DM_NAME_LEN + sizeof(DM_DIR)); > if (!name) { > return -ENOMEM; > }
Sorry, I sent the last patch before I got your email.
Also, the "+1" is still necessary, even if we switch to sizeof. The sprintf call that follows copies DM_DIR, followed by a slash, followed by the name from the hash table into the allocated string. The "+1" is for the slash in the middle. The terminating NULL character is accounted for in DM_NAME_LEN.
Linus, here is (yet another!) patch against current BK.
-- Kevin Corry corryk@us.ibm.com http://evms.sourceforge.net/
--- linux-2.5.63-bk4a/drivers/md/dm-ioctl.c Fri Feb 28 08:43:19 2003 +++ linux-2.5.63-bk4b/drivers/md/dm-ioctl.c Fri Feb 28 08:44:08 2003 @@ -174,7 +174,7 @@ static int register_with_devfs(struct hash_cell *hc) { struct gendisk *disk = dm_disk(hc->md); - char *name = kmalloc(DM_NAME_LEN + strlen(DM_DIR) + 1, GFP_KERNEL); + char *name = kmalloc(DM_NAME_LEN + sizeof(DM_DIR) + 1, GFP_KERNEL); if (!name) { return -ENOMEM; } - 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/
| |