linux/net/rose
Bernard Pidoux 3c53cd65de rose: check NULL rose_loopback_neigh->loopback
Commit 3b3fd068c5 added NULL check for
`rose_loopback_neigh->dev` in rose_loopback_timer() but omitted to
check rose_loopback_neigh->loopback.

It thus prevents *all* rose connect.

The reason is that a special rose_neigh loopback has a NULL device.

/proc/net/rose_neigh illustrates it via rose_neigh_show() function :
[...]
seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
	   rose_neigh->number,
	   (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
	   rose_neigh->dev ? rose_neigh->dev->name : "???",
	   rose_neigh->count,

/proc/net/rose_neigh displays special rose_loopback_neigh->loopback as
callsign RSLOOP-0:

addr  callsign  dev  count use mode restart  t0  tf digipeaters
00001 RSLOOP-0  ???      1   2  DCE     yes   0   0

By checking rose_loopback_neigh->loopback, rose_rx_call_request() is called
even in case rose_loopback_neigh->dev is NULL. This repairs rose connections.

Verification with rose client application FPAC:

FPAC-Node v 4.1.3 (built Aug  5 2022) for LINUX (help = h)
F6BVP-4 (Commands = ?) : u
Users - AX.25 Level 2 sessions :
Port   Callsign     Callsign  AX.25 state  ROSE state  NetRom status
axudp  F6BVP-5   -> F6BVP-9   Connected    Connected   ---------

Fixes: 3b3fd068c5 ("rose: Fix Null pointer dereference in rose_send_frame()")
Signed-off-by: Bernard Pidoux <f6bvp@free.fr>
Suggested-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Thomas DL9SAU Osterried <thomas@osterried.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-22 14:24:54 +01:00
..
af_rose.c net: rose: add netdev ref tracker to 'struct rose_sock' 2022-08-01 11:59:23 -07:00
Makefile
rose_dev.c rose: constify dev_addr passing 2021-10-13 09:40:45 -07:00
rose_in.c net: Don't include filter.h from net/sock.h 2021-12-29 08:48:14 -08:00
rose_link.c ax25: constify dev_addr passing 2021-10-13 09:40:45 -07:00
rose_loopback.c rose: check NULL rose_loopback_neigh->loopback 2022-08-22 14:24:54 +01:00
rose_out.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
rose_route.c net: rose: fix netdev reference changes 2022-08-01 11:59:23 -07:00
rose_subr.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
rose_timer.c net: rose: fix UAF bugs caused by timer handler 2022-06-30 11:07:30 +02:00
sysctl_net_rose.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00