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author | Stanislav Fomichev <sdf@google.com> | 2022-11-21 10:29:13 -0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-12-31 13:14:42 +0100 |
commit | 4b8f3b939266c90f03b7cc7e26a4c28c7b64137b (patch) | |
tree | 4b832ee8b64122bf13b38d7cf16c9807e0c469c8 /drivers/net/ppp/ppp_generic.c | |
parent | 5d5a481a7fd0234f617535dc464ea010804a1129 (diff) |
ppp: associate skb with a device at tx
[ Upstream commit 9f225444467b98579cf28d94f4ad053460dfdb84 ]
Syzkaller triggered flow dissector warning with the following:
r0 = openat$ppp(0xffffffffffffff9c, &(0x7f0000000000), 0xc0802, 0x0)
ioctl$PPPIOCNEWUNIT(r0, 0xc004743e, &(0x7f00000000c0))
ioctl$PPPIOCSACTIVE(r0, 0x40107446, &(0x7f0000000240)={0x2, &(0x7f0000000180)=[{0x20, 0x0, 0x0, 0xfffff034}, {0x6}]})
pwritev(r0, &(0x7f0000000040)=[{&(0x7f0000000140)='\x00!', 0x2}], 0x1, 0x0, 0x0)
[ 9.485814] WARNING: CPU: 3 PID: 329 at net/core/flow_dissector.c:1016 __skb_flow_dissect+0x1ee0/0x1fa0
[ 9.485929] skb_get_poff+0x53/0xa0
[ 9.485937] bpf_skb_get_pay_offset+0xe/0x20
[ 9.485944] ? ppp_send_frame+0xc2/0x5b0
[ 9.485949] ? _raw_spin_unlock_irqrestore+0x40/0x60
[ 9.485958] ? __ppp_xmit_process+0x7a/0xe0
[ 9.485968] ? ppp_xmit_process+0x5b/0xb0
[ 9.485974] ? ppp_write+0x12a/0x190
[ 9.485981] ? do_iter_write+0x18e/0x2d0
[ 9.485987] ? __import_iovec+0x30/0x130
[ 9.485997] ? do_pwritev+0x1b6/0x240
[ 9.486016] ? trace_hardirqs_on+0x47/0x50
[ 9.486023] ? __x64_sys_pwritev+0x24/0x30
[ 9.486026] ? do_syscall_64+0x3d/0x80
[ 9.486031] ? entry_SYSCALL_64_after_hwframe+0x63/0xcd
Flow dissector tries to find skb net namespace either via device
or via socket. Neigher is set in ppp_send_frame, so let's manually
use ppp->dev.
Cc: Paul Mackerras <paulus@samba.org>
Cc: linux-ppp@vger.kernel.org
Reported-by: syzbot+41cab52ab62ee99ed24a@syzkaller.appspotmail.com
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/net/ppp/ppp_generic.c')
-rw-r--r-- | drivers/net/ppp/ppp_generic.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 829d6ada1704..c1f11d1df4cd 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -1742,6 +1742,8 @@ ppp_send_frame(struct ppp *ppp, struct sk_buff *skb) int len; unsigned char *cp; + skb->dev = ppp->dev; + if (proto < 0x8000) { #ifdef CONFIG_PPP_FILTER /* check if we should pass this packet */ |