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: 0 UID: 0 PID: 14769 Comm: syz.1.2880 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 : [<814715e4>] lr : [<814715d4>] psr: 60000013 sp : dfbc9d30 ip : dfbc9d30 fp : dfbc9d54 r10: 82d2ca04 r9 : 00000003 r8 : 8311b180 r7 : dfbc9d90 r6 : 8311b180 r5 : 00000000 r4 : 00000000 r3 : fee0007c r2 : 81e2cec8 r1 : 00000001 r0 : 81471244 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85c2f9c0 DAC: fffffffd 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 8311b180 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfbc8000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2745 Register r8 information: slab kmalloc-192 start 8311b180 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 0xdfbc8000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2745 Register r12 information: 2-page vmalloc region starting at 0xdfbc8000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2745 Process syz.1.2880 (pid: 14769, stack limit = 0xdfbc8000) Stack: (0xdfbc9d30 to 0xdfbca000) 9d20: ffffffff 00000004 82bd5668 82bd5668 9d40: 81e2d388 00000000 dfbc9d8c dfbc9d58 8146d160 8147146c 40946400 00000000 9d60: dfbc9d7c 20000600 8311b180 b5403587 40946400 00000003 00000007 850d6e40 9d80: dfbc9e4c dfbc9d90 8146896c 8146d064 656d6f63 705f6964 6f707261 00007472 9da0: 00000000 0000007c 00000000 00000000 0000000c 00000010 00000006 000007ff 9dc0: 00000c5b 00000005 00000100 00000004 00000001 00000001 0001ffff 00000002 9de0: 00000007 00000083 00000002 01000003 00001b14 00000018 00000000 ffffffff 9e00: ffffffff 0000000b 00000006 0000003b 00000010 10000006 00000660 fffffff8 9e20: 00000000 68b90b91 00000000 86834d00 8311b180 20000600 40946400 00000003 9e40: dfbc9f14 dfbc9e50 81469c90 814688a4 00000000 68b90b91 00000000 00000000 9e60: 8253d804 dfbc9ea4 0000005f 844a9dd8 00000064 8311b1b0 dfbc9ee4 dfbc9e88 9e80: 807fbdcc 807f20fc 00000064 00000001 00000000 dfbc9ea4 858f6010 834e5bb0 9ea0: 00006400 0000000b dfbc9e98 00000000 00000000 68b90b91 00000000 86834d00 9ec0: 40946400 20000600 20000600 86834d00 00000007 850d6e40 dfbc9ef4 dfbc9ee8 9ee0: 807fbf00 68b90b91 dfbc9f14 00000000 86834d01 40946400 20000600 86834d00 9f00: 00000007 850d6e40 dfbc9fa4 dfbc9f18 805b294c 81469948 ecac8b10 850d6e40 9f20: dfbc9f3c dfbc9f30 81b34078 81b33f44 dfbc9f54 dfbc9f40 8025a7e8 8028e4c0 9f40: dfbc9fb0 40000000 dfbc9f84 dfbc9f58 80220bdc 8025a7a4 00000000 82a1ea8c 9f60: dfbc9fb0 0013e9c0 ecac8b10 80220b30 00000000 68b90b91 dfbc9fac 00000000 9f80: 00000000 00346310 00000036 8020029c 850d6e40 00000036 00000000 dfbc9fa8 9fa0: 80200060 805b2714 00000000 00000000 00000007 40946400 20000600 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fe00dc 9fe0: 76fdfe88 76fdfe78 00018ebc 00130820 60000010 00000007 00000000 00000000 Call trace: [<81471460>] (parport_attach) from [<8146d160>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2d388 r4:82bd5668 [<8146d058>] (comedi_device_attach) from [<8146896c>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:930) r10:850d6e40 r9:00000007 r8:00000003 r7:40946400 r6:b5403587 r5:8311b180 r4:20000600 [<81468898>] (do_devconfig_ioctl) from [<81469c90>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:20000600 r5:8311b180 r4:86834d00 [<8146993c>] (comedi_unlocked_ioctl) from [<805b294c>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8146993c>] (comedi_unlocked_ioctl) from [<805b294c>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8146993c>] (comedi_unlocked_ioctl) from [<805b294c>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8146993c>] (comedi_unlocked_ioctl) from [<805b294c>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:850d6e40 r9:00000007 r8:86834d00 r7:20000600 r6:40946400 r5:86834d01 r4:00000000 [<805b2708>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfbc9fa8 to 0xdfbc9ff0) 9fa0: 00000000 00000000 00000007 40946400 20000600 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76fe00dc 9fe0: 76fdfe88 76fdfe78 00018ebc 00130820 r10:00000036 r9:850d6e40 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