From 895493dad60f71c1b71bf86b7aaf1e310d86c245 Mon Sep 17 00:00:00 2001 From: Jan Engelhardt Date: Wed, 2 Mar 2011 12:10:13 +0100 Subject: [PATCH] netfilter: nf_log: avoid oops in (un)bind with invalid nfproto values commit 9ef0298a8e5730d9a46d640014c727f3b4152870 upstream. Like many other places, we have to check that the array index is within allowed limits, or otherwise, a kernel oops and other nastiness can ensue when we access memory beyond the end of the array. [ 5954.115381] BUG: unable to handle kernel paging request at 0000004000000000 [ 5954.120014] IP: __find_logger+0x6f/0xa0 [ 5954.123979] nf_log_bind_pf+0x2b/0x70 [ 5954.123979] nfulnl_recv_config+0xc0/0x4a0 [nfnetlink_log] [ 5954.123979] nfnetlink_rcv_msg+0x12c/0x1b0 [nfnetlink] ... The problem goes back to v2.6.30-rc1~1372~1342~31 where nf_log_bind was decoupled from nf_log_register. Reported-by: Miguel Di Ciurcio Filho , via irc.freenode.net/#netfilter Signed-off-by: Jan Engelhardt Signed-off-by: Patrick McHardy Signed-off-by: Greg Kroah-Hartman --- net/netfilter/nf_log.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c index d65d3481..e54392ee 100644 --- a/net/netfilter/nf_log.c +++ b/net/netfilter/nf_log.c @@ -83,6 +83,8 @@ EXPORT_SYMBOL(nf_log_unregister); int nf_log_bind_pf(u_int8_t pf, const struct nf_logger *logger) { + if (pf >= ARRAY_SIZE(nf_loggers)) + return -EINVAL; mutex_lock(&nf_log_mutex); if (__find_logger(pf, logger->name) == NULL) { mutex_unlock(&nf_log_mutex); @@ -96,6 +98,8 @@ EXPORT_SYMBOL(nf_log_bind_pf); void nf_log_unbind_pf(u_int8_t pf) { + if (pf >= ARRAY_SIZE(nf_loggers)) + return; mutex_lock(&nf_log_mutex); rcu_assign_pointer(nf_loggers[pf], NULL); mutex_unlock(&nf_log_mutex);