This is a note to let you know that I've just added the patch titled nf_conntrack: avoid kernel pointer value leak in slab name to the 4.5-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nf_conntrack-avoid-kernel-pointer-value-leak-in-slab-name.patch and it can be found in the queue-4.5 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 31b0b385f69d8d5491a4bca288e25e63f1d945d0 Mon Sep 17 00:00:00 2001 From: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Date: Sat, 14 May 2016 11:11:44 -0700 Subject: nf_conntrack: avoid kernel pointer value leak in slab name From: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> commit 31b0b385f69d8d5491a4bca288e25e63f1d945d0 upstream. 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@xxxxxxxxxxxxxxxxxxxx> Acked-by: Eric Dumazet <eric.dumazet@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/netfilter/nf_conntrack_core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1780,6 +1780,7 @@ void nf_conntrack_init_end(void) int nf_conntrack_init_net(struct net *net) { + static atomic64_t unique_id; int ret = -ENOMEM; int cpu; @@ -1802,7 +1803,8 @@ int nf_conntrack_init_net(struct net *ne 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; Patches currently in stable-queue which might be from torvalds@xxxxxxxxxxxxxxxxxxxx are queue-4.5/nf_conntrack-avoid-kernel-pointer-value-leak-in-slab-name.patch queue-4.5/ocfs2-fix-posix_acl_create-deadlock.patch queue-4.5/ocfs2-revert-using-ocfs2_acl_chmod-to-avoid-inode-cluster-lock-hang.patch queue-4.5/mm-thp-calculate-the-mapcount-correctly-for-thp-pages-during-wp-faults.patch queue-4.5/perf-core-disable-the-event-on-a-truncated-aux-record.patch queue-4.5/bpf-fix-double-fdput-in-replace_map_fd_with_map_ptr.patch queue-4.5/perf-diff-fix-duplicated-output-column.patch queue-4.5/zsmalloc-fix-zs_can_compact-integer-overflow.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html