diff options
author | Ralf Baechle <ralf@linux-mips.org> | 2017-02-09 14:12:11 +0100 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2017-02-10 13:41:13 -0500 |
commit | 7ba1b689038726d34e3244c1ac9e2e18c2ea4787 (patch) | |
tree | 0487e65f3e5c1f72e1997c1c8f26c99c4f62e334 | |
parent | b85ea006b6bebb692628f11882af41c3e12e1e09 (diff) | |
download | linux-7ba1b689038726d34e3244c1ac9e2e18c2ea4787.tar.bz2 |
NET: mkiss: Fix panic
If a USB-to-serial adapter is unplugged, the driver re-initializes, with
dev->hard_header_len and dev->addr_len set to zero, instead of the correct
values. If then a packet is sent through the half-dead interface, the
kernel will panic due to running out of headroom in the skb when pushing
for the AX.25 headers resulting in this panic:
[<c0595468>] (skb_panic) from [<c0401f70>] (skb_push+0x4c/0x50)
[<c0401f70>] (skb_push) from [<bf0bdad4>] (ax25_hard_header+0x34/0xf4 [ax25])
[<bf0bdad4>] (ax25_hard_header [ax25]) from [<bf0d05d4>] (ax_header+0x38/0x40 [mkiss])
[<bf0d05d4>] (ax_header [mkiss]) from [<c041b584>] (neigh_compat_output+0x8c/0xd8)
[<c041b584>] (neigh_compat_output) from [<c043e7a8>] (ip_finish_output+0x2a0/0x914)
[<c043e7a8>] (ip_finish_output) from [<c043f948>] (ip_output+0xd8/0xf0)
[<c043f948>] (ip_output) from [<c043f04c>] (ip_local_out_sk+0x44/0x48)
This patch makes mkiss behave like the 6pack driver. 6pack does not
panic. In 6pack.c sp_setup() (same function name here) the values for
dev->hard_header_len and dev->addr_len are set to the same values as in
my mkiss patch.
[ralf@linux-mips.org: Massages original submission to conform to the usual
standards for patch submissions.]
Signed-off-by: Thomas Osterried <thomas@osterried.de>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | drivers/net/hamradio/mkiss.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/net/hamradio/mkiss.c b/drivers/net/hamradio/mkiss.c index ece59c54a653..4a40a3d825b4 100644 --- a/drivers/net/hamradio/mkiss.c +++ b/drivers/net/hamradio/mkiss.c @@ -648,8 +648,8 @@ static void ax_setup(struct net_device *dev) { /* Finish setting up the DEVICE info. */ dev->mtu = AX_MTU; - dev->hard_header_len = 0; - dev->addr_len = 0; + dev->hard_header_len = AX25_MAX_HEADER_LEN; + dev->addr_len = AX25_ADDR_LEN; dev->type = ARPHRD_AX25; dev->tx_queue_len = 10; dev->header_ops = &ax25_header_ops; |