CVE-2013-4514 (published 2013-11-12T14:35Z)

Multiple buffer overflows in drivers/staging/wlags49_h2/wl_priv.c in the Linux kernel before 3.12 allow local users to cause a denial of service or possibly have unspecified other impact by leveraging the CAP_NET_ADMIN capability and providing a long station-name string, related to the (1) wvlan_uil_put_info and (2) wvlan_set_station_nickname functions.

Severity: MEDIUM
CVSS v2 base score: 4.7 (AV:L/AC:M/Au:N/C:N/I:N/A:C)

Weakness information:
cwe_id: CWE-119
cwe_name: Improper Restriction of Operations within the Bounds of a Memory Buffer
description: The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
extended_description: 
            Certain languages allow direct addressing of memory locations and do not automatically ensure that these locations are valid for the memory buffer that is being referenced. This can cause read or write operations to be performed on memory locations that may be associated with other variables, data structures, or internal program data.
         
         

Fix information:
repo_url: https://github.com/torvalds/linux
commit_details: repo_url: https://github.com/torvalds/linux
author: Dan Carpenter
author_date: 2013-10-29 23:00:15+03:00
msg: staging: wlags49_h2: buffer overflow setting station name

We need to check the length parameter before doing the memcpy().  I've
actually changed it to strlcpy() as well so that it's NUL terminated.

You need CAP_NET_ADMIN to trigger these so it's not the end of the
world.

Reported-by: Nico Golde <nico@ngolde.de>
Reported-by: Fabian Yamaguchi <fabs@goesec.de>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
repository: repo_url: https://github.com/torvalds/linux
repo_name: torvalds/linux
description: Linux kernel source tree
repo_language: C
owner: torvalds
file_changes: filename: wl_priv.c
change_type: ModificationType.MODIFY
diff: @@ -570,6 +570,7 @@ int wvlan_uil_put_info(struct uilreq *urq, struct wl_private *lp)
 	ltv_t                   *pLtv;
 	bool_t                  ltvAllocated = FALSE;
 	ENCSTRCT                sEncryption;
+	size_t			len;
 
 #ifdef USE_WDS
 	hcf_16                  hcfPort  = HCF_PORT_0;
@@ -686,7 +687,8 @@ int wvlan_uil_put_info(struct uilreq *urq, struct wl_private *lp)
 					break;
 				case CFG_CNF_OWN_NAME:
 					memset(lp->StationName, 0, sizeof(lp->StationName));
-					memcpy((void *)lp->StationName, (void *)&pLtv->u.u8[2], (size_t)pLtv->u.u16[0]);
+					len = min_t(size_t, pLtv->u.u16[0], sizeof(lp->StationName));
+					strlcpy(lp->StationName, &pLtv->u.u8[2], len);
 					pLtv->u.u16[0] = CNV_INT_TO_LITTLE(pLtv->u.u16[0]);
 					break;
 				case CFG_CNF_LOAD_BALANCING:
@@ -1783,6 +1785,7 @@ int wvlan_set_station_nickname(struct net_device *dev,
 {
 	struct wl_private *lp = wl_priv(dev);
 	unsigned long flags;
+	size_t len;
 	int         ret = 0;
 	/*------------------------------------------------------------------------*/
 
@@ -1793,8 +1796,8 @@ int wvlan_set_station_nickname(struct net_device *dev,
 	wl_lock(lp, &flags);
 
 	memset(lp->StationName, 0, sizeof(lp->StationName));
-
-	memcpy(lp->StationName, extra, wrqu->data.length);
+	len = min_t(size_t, wrqu->data.length, sizeof(lp->StationName));
+	strlcpy(lp->StationName, extra, len);
 
 	/* Commit the adapter parameters */
 	wl_apply(lp);

programming_language: C