8<--- cut here --- Unable to handle kernel paging request at virtual address fee00100 when write [fee00100] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 20721 Comm: syz.8.3763 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 : [<81493794>] lr : [<81493784>] psr: 60000013 sp : dfa1dd30 ip : dfa1dd30 fp : dfa1dd54 r10: 82d30dfc r9 : 00000003 r8 : 84276240 r7 : dfa1dd90 r6 : 84276240 r5 : 00000000 r4 : 00000000 r3 : fee00100 r2 : 81e2dee8 r1 : 00000001 r0 : 814933f4 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8c6701c0 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 84276240 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfa1c000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r8 information: slab kmalloc-192 start 84276240 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 0xdfa1c000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r12 information: 2-page vmalloc region starting at 0xdfa1c000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Process syz.8.3763 (pid: 20721, stack limit = 0xdfa1c000) Stack: (0xdfa1dd30 to 0xdfa1e000) dd20: 824d49b8 84276240 82bd8ea0 82bd8ea0 dd40: 81e2e3a8 00000000 dfa1dd8c dfa1dd58 8148f310 8149361c 40946400 00000000 dd60: dfa1dd7c 200000c0 84276240 b5403587 40946400 00000000 00000003 83183d40 dd80: dfa1de4c dfa1dd90 8148ab14 8148f214 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00000100 00004005 00000300 000000e1 0000000e 00000001 00000069 ddc0: 00010000 00000003 00000000 00000009 00000005 00000007 00000001 00000001 dde0: 000000fd fffffff4 000107ff 00000002 00000004 00000089 000007ff 00080000 de00: 20001e58 000007ff 0000f39d 00000006 00000008 0000a4b5 00000000 fffffff8 de20: 00000000 8fa695c2 00000000 864e0900 84276240 200000c0 40946400 00000000 de40: dfa1df14 dfa1de50 8148be3c 8148aa54 00000000 8fa695c2 00000000 00000000 de60: 8254980c dfa1dea4 0000005f 84a32990 00000064 84276270 dfa1dee4 dfa1de88 de80: 80806188 807fc404 00000064 00000001 00000000 dfa1dea4 84fc6b10 834e5880 dea0: 00006400 0000000b dfa1de98 00000000 00000000 8fa695c2 00000000 864e0900 dec0: 40946400 200000c0 200000c0 864e0900 00000003 83183d40 dfa1def4 dfa1dee8 dee0: 808062bc 8fa695c2 dfa1df14 00000000 864e0901 40946400 200000c0 864e0900 df00: 00000003 83183d40 dfa1dfa4 dfa1df18 805bab28 8148baf4 ecac8b10 83183d40 df20: dfa1df3c dfa1df30 81b58240 81b5810c dfa1df54 dfa1df40 8025a7a8 8028e490 df40: dfa1dfb0 40000000 dfa1df84 dfa1df58 80220bdc 8025a764 00000000 82a1eb0c df60: dfa1dfb0 0013e9c0 ecac8b10 80220b30 00000000 8fa695c2 dfa1dfac 00000000 df80: 00000000 00356310 00000036 8020029c 83183d40 00000036 00000000 dfa1dfa8 dfa0: 80200060 805ba8f0 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76fe30dc dfe0: 76fe2e88 76fe2e78 00018ebc 00130820 60000010 00000003 00000000 00000000 Call trace: [<81493610>] (parport_attach) from [<8148f310>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r6:00000000 r5:81e2e3a8 r4:82bd8ea0 [<8148f208>] (comedi_device_attach) from [<8148ab14>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:83183d40 r9:00000003 r8:00000000 r7:40946400 r6:b5403587 r5:84276240 r4:200000c0 [<8148aa48>] (do_devconfig_ioctl) from [<8148be3c>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000000 r7:40946400 r6:200000c0 r5:84276240 r4:864e0900 [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8148bae8>] (comedi_unlocked_ioctl) from [<805bab28>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:83183d40 r9:00000003 r8:864e0900 r7:200000c0 r6:40946400 r5:864e0901 r4:00000000 [<805ba8e4>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa1dfa8 to 0xdfa1dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76fe30dc dfe0: 76fe2e88 76fe2e78 00018ebc 00130820 r10:00000036 r9:83183d40 r8:8020029c r7:00000036 r6:00356310 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