lkml.org 
[lkml]   [2011]   [May]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[131/143] niu: Fix kernel buffer overflow for ETHTOOL_GRXCLSRLALL
2.6.32-longterm review patch.  If anyone has any objections, please let us know.

------------------
From: Ben Hutchings <bhutchings@solarflare.com>

commit ee9c5cfad29c8a13199962614b9b16f1c4137ac9 upstream.

niu_get_ethtool_tcam_all() assumes that its output buffer is the right
size, and warns before returning if it is not. However, the output
buffer size is under user control and ETHTOOL_GRXCLSRLALL is an
unprivileged ethtool command. Therefore this is at least a local
denial-of-service vulnerability.

Change it to check before writing each entry and to return an error if
the buffer is already full.

Compile-tested only.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[Adjusted to apply to 2.6.32 by dann frazier <dannf@debian.org>]
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
drivers/net/niu.c | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)
--- a/drivers/net/niu.c
+++ b/drivers/net/niu.c
@@ -7315,33 +7315,28 @@ static int niu_get_ethtool_tcam_all(stru
struct niu_parent *parent = np->parent;
struct niu_tcam_entry *tp;
int i, idx, cnt;
- u16 n_entries;
unsigned long flags;
-
+ int ret = 0;

/* put the tcam size here */
nfc->data = tcam_get_size(np);

niu_lock_parent(np, flags);
- n_entries = nfc->rule_cnt;
for (cnt = 0, i = 0; i < nfc->data; i++) {
idx = tcam_get_index(np, i);
tp = &parent->tcam[idx];
if (!tp->valid)
continue;
+ if (cnt == nfc->rule_cnt) {
+ ret = -EMSGSIZE;
+ break;
+ }
rule_locs[cnt] = i;
cnt++;
}
niu_unlock_parent(np, flags);

- if (n_entries != cnt) {
- /* print warning, this should not happen */
- pr_info(PFX "niu%d: %s In niu_get_ethtool_tcam_all, "
- "n_entries[%d] != cnt[%d]!!!\n\n",
- np->parent->index, np->dev->name, n_entries, cnt);
- }
-
- return 0;
+ return ret;
}

static int niu_get_nfc(struct net_device *dev, struct ethtool_rxnfc *cmd,



\
 
 \ /
  Last update: 2011-05-06 02:41    [from the cache]
©2003-2011 Jasper Spaans