Alexey Dobriyan
9ac0be9d4f
[AX25]: don't free pointers to statically allocated data
commit 8d5cf596d1 started to add statically
allocated ax25_protocol's to list. However kfree() was still in place waiting
for unsuspecting ones on module removal.
Steps to reproduce:
modprobe netrom
rmmod netrom
P.S.: code would benefit greatly from list_add/list_del usage
kernel BUG at mm/slab.c:592!
invalid opcode: 0000 [1] PREEMPT SMP
CPU 0
Modules linked in: netrom ax25 af_packet usbcore rtc_cmos rtc_core rtc_lib
Pid: 4477, comm: rmmod Not tainted 2.6.23-rc3-bloat #2
RIP: 0010:[<ffffffff802ac646>] [<ffffffff802ac646>] kfree+0x1c6/0x260
RSP: 0000:ffff810079a05e48 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff81000000c000
RDX: ffff81007e552458 RSI: 0000000000000000 RDI: 000000000000805d
RBP: ffff810079a05e88 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8805d080
R13: ffffffff8805d080 R14: 0000000000000000 R15: 0000000000000282
FS: 00002b73fc98aae0(0000) GS:ffffffff805dc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 000000000053f3b8 CR3: 0000000079ff2000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process rmmod (pid: 4477, threadinfo ffff810079a04000, task ffff8100775aa480)
Stack: ffff810079a05e68 0000000000000246 ffffffff8804eca0 0000000000000000
ffffffff8805d080 00000000000000cf 0000000000000000 0000000000000880
ffff810079a05eb8 ffffffff8803ec90 ffff810079a05eb8 0000000000000000
Call Trace:
[<ffffffff8803ec90>] :ax25:ax25_protocol_release+0xa0/0xb0
[<ffffffff88056ecb>] :netrom:nr_exit+0x6b/0xf0
[<ffffffff80268bf0>] sys_delete_module+0x170/0x1f0
[<ffffffff8025da35>] trace_hardirqs_on+0xd5/0x170
[<ffffffff804835aa>] trace_hardirqs_on_thunk+0x35/0x37
[<ffffffff8020c13e>] system_call+0x7e/0x83
Code: 0f 0b eb fe 66 66 90 66 66 90 48 8b 52 10 48 8b 02 25 00 40
RIP [<ffffffff802ac646>] kfree+0x1c6/0x260
RSP <ffff810079a05e48>
Kernel panic - not syncing: Fatal exception
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>