diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-05-14 11:11:44 -0700 |
|---|---|---|
| committer | Sasha Levin <sasha.levin@oracle.com> | 2016-05-17 13:43:15 -0400 |
| commit | 8de861b16d946b7c0ce246fcbb65d550c357c65c (patch) | |
| tree | 13ca0420fddf585e8c5d886a01d12cddcb90c623 | |
| parent | 631598a5c08505c92348b3907824072d0c1000ab (diff) | |
nf_conntrack: avoid kernel pointer value leak in slab name
[ Upstream commit 31b0b385f69d8d5491a4bca288e25e63f1d945d0 ]
The slab name ends up being visible in the directory structure under
/sys, and even if you don't have access rights to the file you can see
the filenames.
Just use a 64-bit counter instead of the pointer to the 'net' structure
to generate a unique name.
This code will go away in 4.7 when the conntrack code moves to a single
kmemcache, but this is the backportable simple solution to avoiding
leaking kernel pointers to user space.
Fixes: 5b3501faa874 ("netfilter: nf_conntrack: per netns nf_conntrack_cachep")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
| -rw-r--r-- | net/netfilter/nf_conntrack_core.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 13fad8668f83..bc3f791845aa 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1735,6 +1735,7 @@ void nf_conntrack_init_end(void) int nf_conntrack_init_net(struct net *net) { + static atomic64_t unique_id; int ret = -ENOMEM; int cpu; @@ -1758,7 +1759,8 @@ int nf_conntrack_init_net(struct net *net) if (!net->ct.stat) goto err_pcpu_lists; - net->ct.slabname = kasprintf(GFP_KERNEL, "nf_conntrack_%p", net); + net->ct.slabname = kasprintf(GFP_KERNEL, "nf_conntrack_%llu", + (u64)atomic64_inc_return(&unique_id)); if (!net->ct.slabname) goto err_slabname; |