8<--- cut here --- Unable to handle kernel paging request at virtual address fee0007c when write [fee0007c] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 9195 Comm: syz.1.1396 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:99 [inline] PC is at parport_attach drivers/comedi/drivers/comedi_parport.c:291 [inline] PC is at parport_attach+0x184/0x1e0 drivers/comedi/drivers/comedi_parport.c:224 LR is at parport_attach drivers/comedi/drivers/comedi_parport.c:291 [inline] LR is at parport_attach+0x174/0x1e0 drivers/comedi/drivers/comedi_parport.c:224 pc : [<8148eb84>] lr : [<8148eb74>] psr: 60000013 sp : e02a5d30 ip : e02a5d30 fp : e02a5d54 r10: 82d30df4 r9 : 00000003 r8 : 842fa780 r7 : e02a5d90 r6 : 842fa780 r5 : 00000000 r4 : 00000000 r3 : fee0007c r2 : 81e2d848 r1 : 00000001 r0 : 8148e7e4 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 86a06c80 DAC: 00000000 Register r0 information: non-slab/vmalloc memory Register r1 information: non-paged memory Register r2 information: non-slab/vmalloc memory Register r3 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1048 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 842fa780 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xe02a4000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2746 Register r8 information: slab kmalloc-192 start 842fa780 pointer offset 0 size 192 Register r9 information: non-paged memory Register r10 information: non-slab/vmalloc memory Register r11 information: 2-page vmalloc region starting at 0xe02a4000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2746 Register r12 information: 2-page vmalloc region starting at 0xe02a4000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2746 Process syz.1.1396 (pid: 9195, stack limit = 0xe02a4000) Stack: (0xe02a5d30 to 0xe02a6000) 5d20: 824d2d60 842fa780 82bd8e04 82bd8e04 5d40: 81e2dd08 00000000 e02a5d8c e02a5d58 8148a700 8148ea0c 40946400 00000000 5d60: e02a5d7c 20000180 842fa780 b5403587 40946400 00000003 00000003 83fb4980 5d80: e02a5e4c e02a5d90 81485f04 8148a604 656d6f63 705f6964 6f707261 00007472 5da0: 00000000 0000007c 00000006 00000000 0000000c 00000010 00000006 008007ff 5dc0: 00000c5b 00000005 00004100 00000004 00000002 00000001 0001ffff 00000002 5de0: 00000007 00000083 00000002 01000003 00001b14 00000018 00000000 ffffffff 5e00: fffffffb 0000000b 00000142 0000003b 00000010 10000406 00000660 fffffff8 5e20: 00000000 0efefc6d 00000000 86039080 842fa780 20000180 40946400 00000003 5e40: e02a5f14 e02a5e50 8148722c 81485e44 00000000 0efefc6d 00000000 00000000 5e60: 8254780c e02a5ea4 0000005f 841a4990 00000064 842fa7b0 e02a5ee4 e02a5e88 5e80: 80803604 807f9934 00000064 00000001 00000000 e02a5ea4 838b9810 83437660 5ea0: 00006400 0000000b e02a5e98 00000000 00000000 0efefc6d 00000000 86039080 5ec0: 40946400 20000180 20000180 86039080 00000003 83fb4980 e02a5ef4 e02a5ee8 5ee0: 80803738 0efefc6d e02a5f14 00000000 86039081 40946400 20000180 86039080 5f00: 00000003 83fb4980 e02a5fa4 e02a5f18 805ba698 81486ee4 ecac8b10 83fb4980 5f20: e02a5f3c e02a5f30 81b52020 81b51eec e02a5f54 e02a5f40 8025a790 8028e468 5f40: e02a5fb0 40000000 e02a5f84 e02a5f58 80220bdc 8025a74c 00000000 82a1eb0c 5f60: e02a5fb0 0013e9c0 ecac8b10 80220b30 00000000 0efefc6d e02a5fac 00000000 5f80: 00000000 00346310 00000036 8020029c 83fb4980 00000036 00000000 e02a5fa8 5fa0: 80200060 805ba460 00000000 00000000 00000003 40946400 20000180 00000000 5fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fa90dc 5fe0: 76fa8e88 76fa8e78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<8148ea00>] (parport_attach) from [<8148a700>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2dd08 r4:82bd8e04 [<8148a5f8>] (comedi_device_attach) from [<81485f04>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:83fb4980 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:842fa780 r4:20000180 [<81485e38>] (do_devconfig_ioctl) from [<8148722c>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:20000180 r5:842fa780 r4:86039080 [<81486ed8>] (comedi_unlocked_ioctl) from [<805ba698>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81486ed8>] (comedi_unlocked_ioctl) from [<805ba698>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81486ed8>] (comedi_unlocked_ioctl) from [<805ba698>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81486ed8>] (comedi_unlocked_ioctl) from [<805ba698>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:83fb4980 r9:00000003 r8:86039080 r7:20000180 r6:40946400 r5:86039081 r4:00000000 [<805ba454>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe02a5fa8 to 0xe02a5ff0) 5fa0: 00000000 00000000 00000003 40946400 20000180 00000000 5fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fa90dc 5fe0: 76fa8e88 76fa8e78 00018ebc 00130820 r10:00000036 r9:83fb4980 r8:8020029c r7:00000036 r6:00346310 r5:00000000 r4:00000000 Code: e5963064 e3a04000 e7f33053 e2433612 (e5c34000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e5963064 ldr r3, [r6, #100] @ 0x64 4: e3a04000 mov r4, #0 8: e7f33053 ubfx r3, r3, #0, #20 c: e2433612 sub r3, r3, #18874368 @ 0x1200000 * 10: e5c34000 strb r4, [r3] <-- trapping instruction