summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorHaixia Qu <hxqu@hillstonenet.com>2025-06-17 05:56:24 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2025-06-27 11:11:43 +0100
commit0d3d91c3500f0c480e016faa4e2259c588616e59 (patch)
treebcfabc40cc1dabca4d9392b0e3c35ef43c58e1b2
parent397c1faf8fde78325e5cbb3bb72351006fe673ad (diff)
tipc: fix null-ptr-deref when acquiring remote ip of ethernet bearer
[ Upstream commit f82727adcf2992822e12198792af450a76ebd5ef ] The reproduction steps: 1. create a tun interface 2. enable l2 bearer 3. TIPC_NL_UDP_GET_REMOTEIP with media name set to tun tipc: Started in network mode tipc: Node identity 8af312d38a21, cluster identity 4711 tipc: Enabled bearer <eth:syz_tun>, priority 1 Oops: general protection fault KASAN: null-ptr-deref in range CPU: 1 UID: 1000 PID: 559 Comm: poc Not tainted 6.16.0-rc1+ #117 PREEMPT Hardware name: QEMU Ubuntu 24.04 PC RIP: 0010:tipc_udp_nl_dump_remoteip+0x4a4/0x8f0 the ub was in fact a struct dev. when bid != 0 && skip_cnt != 0, bearer_list[bid] may be NULL or other media when other thread changes it. fix this by checking media_id. Fixes: 832629ca5c313 ("tipc: add UDP remoteip dump to netlink API") Signed-off-by: Haixia Qu <hxqu@hillstonenet.com> Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech> Link: https://patch.msgid.link/20250617055624.2680-1-hxqu@hillstonenet.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
-rw-r--r--net/tipc/udp_media.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
index 108a4cc2e001..258d6aa4f21a 100644
--- a/net/tipc/udp_media.c
+++ b/net/tipc/udp_media.c
@@ -489,7 +489,7 @@ int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb)
rtnl_lock();
b = tipc_bearer_find(net, bname);
- if (!b) {
+ if (!b || b->bcast_addr.media_id != TIPC_MEDIA_TYPE_UDP) {
rtnl_unlock();
return -EINVAL;
}
@@ -500,7 +500,7 @@ int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb)
rtnl_lock();
b = rtnl_dereference(tn->bearer_list[bid]);
- if (!b) {
+ if (!b || b->bcast_addr.media_id != TIPC_MEDIA_TYPE_UDP) {
rtnl_unlock();
return -EINVAL;
}