From b77413446408fdd256599daf00d5be72b5f3e7c6 Mon Sep 17 00:00:00 2001
From: Hoang Le <hoang.h.le@dektech.com.au>
Date: Fri, 8 Jan 2021 14:13:37 +0700
Subject: tipc: fix NULL deref in tipc_link_xmit()
The buffer list can have zero skb as following path:
tipc_named_node_up()->tipc_node_xmit()->tipc_link_xmit(), so
we need to check the list before casting an &sk_buff.
Fault report:
[] tipc: Bulk publication failure
[] general protection fault, probably for non-canonical [#1] PREEMPT [...]
[] KASAN: null-ptr-deref in range [0x00000000000000c8-0x00000000000000cf]
[] CPU: 0 PID: 0 Comm: swapper/0 Kdump: loaded Not tainted 5.10.0-rc4+ #2
[] Hardware name: Bochs ..., BIOS Bochs 01/01/2011
[] RIP: 0010:tipc_link_xmit+0xc1/0x2180
[] Code: 24 b8 00 00 00 00 4d 39 ec 4c 0f 44 e8 e8 d7 0a 10 f9 48 [...]
[] RSP: 0018:ffffc90000006ea0 EFLAGS: 00010202
[] RAX: dffffc0000000000 RBX: ffff8880224da000 RCX: 1ffff11003d3cc0d
[] RDX: 0000000000000019 RSI: ffffffff886007b9 RDI: 00000000000000c8
[] RBP: ffffc90000007018 R08: 0000000000000001 R09: fffff52000000ded
[] R10: 0000000000000003 R11: fffff52000000dec R12: ffffc90000007148
[] R13: 0000000000000000 R14: 0000000000000000 R15: ffffc90000007018
[] FS: 0000000000000000(0000) GS:ffff888037400000(0000) knlGS:000[...]
[] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[] CR2: 00007fffd2db5000 CR3: 000000002b08f000 CR4: 00000000000006f0
Fixes: af9b028e270fd ("tipc: make media xmit call outside node spinlock context")
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Link: https://lore.kernel.org/r/20210108071337.3598-1-hoang.h.le@dektech.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
net/tipc/link.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
(limited to 'net/tipc')
diff --git a/net/tipc/link.c b/net/tipc/link.c
index 6ae2140eb4f7..a6a694b78927 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1030,7 +1030,6 @@ void tipc_link_reset(struct tipc_link *l)
int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
struct sk_buff_head *xmitq)
{
- struct tipc_msg *hdr = buf_msg(skb_peek(list));
struct sk_buff_head *backlogq = &l->backlogq;
struct sk_buff_head *transmq = &l->transmq;
struct sk_buff *skb, *_skb;
@@ -1038,13 +1037,18 @@ int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
u16 ack = l->rcv_nxt - 1;
u16 seqno = l->snd_nxt;
int pkt_cnt = skb_queue_len(list);
- int imp = msg_importance(hdr);
unsigned int mss = tipc_link_mss(l);
unsigned int cwin = l->window;
unsigned int mtu = l->mtu;
+ struct tipc_msg *hdr;
bool new_bundle;
int rc = 0;
+ int imp;
+
+ if (pkt_cnt <= 0)
+ return 0;
+ hdr = buf_msg(skb_peek(list));
if (unlikely(msg_size(hdr) > mtu)) {
pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
skb_queue_len(list), msg_user(hdr),
@@ -1053,6 +1057,7 @@ int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
return -EMSGSIZE;
}
+ imp = msg_importance(hdr);
/* Allow oversubscription of one data msg per source at congestion */
if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
if (imp == TIPC_SYSTEM_IMPORTANCE) {
--
cgit v1.2.3
From 25764779298f23a659f3daf39f9e2b5975a7a89d Mon Sep 17 00:00:00 2001
From: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Date: Thu, 14 Jan 2021 09:04:48 +0100
Subject: net: tip: fix a couple kernel-doc markups
A function has a different name between their prototype
and its kernel-doc markup:
../net/tipc/link.c:2551: warning: expecting prototype for link_reset_stats(). Prototype was for tipc_link_reset_stats() instead
../net/tipc/node.c:1678: warning: expecting prototype for is the general link level function for message sending(). Prototype was for tipc_node_xmit() instead
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
net/tipc/link.c | 2 +-
net/tipc/node.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
(limited to 'net/tipc')
diff --git a/net/tipc/link.c b/net/tipc/link.c
index a6a694b78927..115109259430 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -2544,7 +2544,7 @@ void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
}
/**
- * link_reset_stats - reset link statistics
+ * tipc_link_reset_stats - reset link statistics
* @l: pointer to link
*/
void tipc_link_reset_stats(struct tipc_link *l)
diff --git a/net/tipc/node.c b/net/tipc/node.c
index 83d9eb830592..008670d1f43e 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -1665,7 +1665,7 @@ static void tipc_lxc_xmit(struct net *peer_net, struct sk_buff_head *list)
}
/**
- * tipc_node_xmit() is the general link level function for message sending
+ * tipc_node_xmit() - general link level function for message sending
* @net: the applicable net namespace
* @list: chain of buffers containing message
* @dnode: address of destination node
--
cgit v1.2.3