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| author | Stanislav Fomichev <sdf@google.com> | 2022-11-21 19:29:13 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-11-23 13:54:18 +0100 |
| commit | 9f225444467b98579cf28d94f4ad053460dfdb84 (patch) | |
| tree | 9387259a003df45a0608bba55c88a5f263176121 /drivers/net/ppp/ppp_generic.c | |
| parent | Documentation: devlink: Add blank line padding on numbered lists in Devlink P... (diff) | |
| download | linux-9f225444467b98579cf28d94f4ad053460dfdb84.tar.xz linux-9f225444467b98579cf28d94f4ad053460dfdb84.zip | |
ppp: associate skb with a device at tx
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>
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 9206c660a72e..d4c821c8cf57 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -1743,6 +1743,8 @@ 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 */ |