linux/drivers/net/hamradio
Eric Dumazet 202700e307 net/hamradio/6pack: use mod_timer() to rearm timers
Using del_timer() + add_timer() is generally unsafe on SMP,
as noticed by syzbot. Use mod_timer() instead.

kernel BUG at kernel/time/timer.c:1136!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 1026 Comm: kworker/u4:4 Not tainted 4.20.0+ #2
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound flush_to_ldisc
RIP: 0010:add_timer kernel/time/timer.c:1136 [inline]
RIP: 0010:add_timer+0xa81/0x1470 kernel/time/timer.c:1134
Code: 4d 89 7d 40 48 c7 85 70 fe ff ff 00 00 00 00 c7 85 7c fe ff ff ff ff ff ff 48 89 85 90 fe ff ff e9 e6 f7 ff ff e8 cf 42 12 00 <0f> 0b e8 c8 42 12 00 0f 0b e8 c1 42 12 00 4c 89 bd 60 fe ff ff e9
RSP: 0018:ffff8880a7fdf5a8 EFLAGS: 00010293
RAX: ffff8880a7846340 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff816f3ee1 RDI: ffff88808a514ff8
RBP: ffff8880a7fdf760 R08: 0000000000000007 R09: ffff8880a7846c58
R10: ffff8880a7846340 R11: 0000000000000000 R12: ffff88808a514ff8
R13: ffff88808a514ff8 R14: ffff88808a514dc0 R15: 0000000000000030
FS:  0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000061c500 CR3: 00000000994d9000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 decode_prio_command drivers/net/hamradio/6pack.c:903 [inline]
 sixpack_decode drivers/net/hamradio/6pack.c:971 [inline]
 sixpack_receive_buf drivers/net/hamradio/6pack.c:457 [inline]
 sixpack_receive_buf+0xf9c/0x1470 drivers/net/hamradio/6pack.c:434
 tty_ldisc_receive_buf+0x164/0x1c0 drivers/tty/tty_buffer.c:465
 tty_port_default_receive_buf+0x114/0x190 drivers/tty/tty_port.c:38
 receive_buf drivers/tty/tty_buffer.c:481 [inline]
 flush_to_ldisc+0x3b2/0x590 drivers/tty/tty_buffer.c:533
 process_one_work+0xd0c/0x1ce0 kernel/workqueue.c:2153
 worker_thread+0x143/0x14a0 kernel/workqueue.c:2296
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Andreas Koensgen <ajk@comnets.uni-bremen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-02 10:27:01 -08:00
..
6pack.c net/hamradio/6pack: use mod_timer() to rearm timers 2019-01-02 10:27:01 -08:00
baycom_epp.c hamradio: baycom: use new parport device model 2017-09-18 16:40:25 -07:00
baycom_par.c hamradio: baycom_par: use new parport device model 2017-10-16 21:16:23 +01:00
baycom_ser_fdx.c hamradio: baycom: make hdlcdrv_ops const 2017-08-07 14:26:46 -07:00
baycom_ser_hdx.c hamradio: baycom: make hdlcdrv_ops const 2017-08-07 14:26:46 -07:00
bpqether.c net: hamradio: use eth_broadcast_addr 2018-06-20 07:51:43 +09:00
dmascc.c hamradio: dmascc: avoid -Wformat-overflow warning 2017-07-26 09:32:44 -07:00
hdlcdrv.c hdlcdrv: Fix divide by zero in hdlcdrv_ioctl 2017-05-27 18:44:17 -04:00
Kconfig tty: Added a CONFIG_TTY option to allow removal of TTY 2013-01-18 16:15:27 -08:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mkiss.c hamradio, ppp: change semaphore to completion 2018-12-14 13:27:10 -08:00
scc.c proc: introduce proc_create_seq{,_data} 2018-05-16 07:23:35 +02:00
yam.c yam: fix a missing-check bug 2018-10-05 11:54:55 -07:00
z8530.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00