5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit 8588c99c7d47448fcae39e3227d6e2bb97aad86d ]
We should not assume mac header is set in output path.
Use skb_eth_hdr() instead of eth_hdr() to fix the issue.
sysbot reported the following :
WARNING: CPU: 0 PID: 11635 at include/linux/skbuff.h:3052 skb_mac_header include/linux/skbuff.h:3052 [inline]
WARNING: CPU: 0 PID: 11635 at include/linux/skbuff.h:3052 eth_hdr include/linux/if_ether.h:24 [inline]
WARNING: CPU: 0 PID: 11635 at include/linux/skbuff.h:3052 geneve_xmit_skb drivers/net/geneve.c:898 [inline]
WARNING: CPU: 0 PID: 11635 at include/linux/skbuff.h:3052 geneve_xmit+0x4c38/0x5730 drivers/net/geneve.c:1039
Modules linked in:
CPU: 0 UID: 0 PID: 11635 Comm: syz.4.1423 Not tainted 6.12.0-syzkaller-10296-gaaf20f870da0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:skb_mac_header include/linux/skbuff.h:3052 [inline]
RIP: 0010:eth_hdr include/linux/if_ether.h:24 [inline]
RIP: 0010:geneve_xmit_skb drivers/net/geneve.c:898 [inline]
RIP: 0010:geneve_xmit+0x4c38/0x5730 drivers/net/geneve.c:1039
Code: 21 c6 02 e9 35 d4 ff ff e8 a5 48 4c fb 90 0f 0b 90 e9 fd f5 ff ff e8 97 48 4c fb 90 0f 0b 90 e9 d8 f5 ff ff e8 89 48 4c fb 90 <0f> 0b 90 e9 41 e4 ff ff e8 7b 48 4c fb 90 0f 0b 90 e9 cd e7 ff ff
RSP: 0018:ffffc90003b2f870 EFLAGS: 00010283
RAX: 000000000000037a RBX: 000000000000ffff RCX: ffffc9000dc3d000
RDX: 0000000000080000 RSI: ffffffff86428417 RDI: 0000000000000003
RBP: ffffc90003b2f9f0 R08: 0000000000000003 R09: 000000000000ffff
R10: 000000000000ffff R11: 0000000000000002 R12: ffff88806603c000
R13: 0000000000000000 R14: ffff8880685b2780 R15: 0000000000000e23
FS: 00007fdc2deed6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30a1dff8 CR3: 0000000056b8c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__netdev_start_xmit include/linux/netdevice.h:5002 [inline]
netdev_start_xmit include/linux/netdevice.h:5011 [inline]
__dev_direct_xmit+0x58a/0x720 net/core/dev.c:4490
dev_direct_xmit include/linux/netdevice.h:3181 [inline]
packet_xmit+0x1e4/0x360 net/packet/af_packet.c:285
packet_snd net/packet/af_packet.c:3146 [inline]
packet_sendmsg+0x2700/0x5660 net/packet/af_packet.c:3178
sock_sendmsg_nosec net/socket.c:711 [inline]
__sock_sendmsg net/socket.c:726 [inline]
__sys_sendto+0x488/0x4f0 net/socket.c:2197
__do_sys_sendto net/socket.c:2204 [inline]
__se_sys_sendto net/socket.c:2200 [inline]
__x64_sys_sendto+0xe0/0x1c0 net/socket.c:2200
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Fixes: a025fb5f49ad ("geneve: Allow configuration of DF behaviour")
Reported-by: syzbot+3ec5271486d7cb2d242a@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://lore.kernel.org/netdev/674f4b72.050a0220.17bd51.004a.GAE@xxxxxxxxxx/T/#u
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reviewed-by: Stefano Brivio <sbrivio@xxxxxxxxxx>
Link: https://patch.msgid.link/20241203182122.2725517-1-edumazet@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/geneve.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index d0b7d1b922218..e7412edb84dcd 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -983,7 +983,7 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
if (geneve->cfg.df == GENEVE_DF_SET) {
df = htons(IP_DF);
} else if (geneve->cfg.df == GENEVE_DF_INHERIT) {
- struct ethhdr *eth = eth_hdr(skb);
+ struct ethhdr *eth = skb_eth_hdr(skb);
if (ntohs(eth->h_proto) == ETH_P_IPV6) {
df = htons(IP_DF);
--
2.43.0
