8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f27 when write [fee04f27] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 752 Comm: syz.2.6537 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:88 [inline] PC is at parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] PC is at parport_attach+0x174/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 LR is at parport_attach drivers/comedi/drivers/comedi_parport.c:289 [inline] LR is at parport_attach+0x164/0x1d0 drivers/comedi/drivers/comedi_parport.c:224 pc : [<813abc58>] lr : [<813abc48>] psr: 60000013 sp : dfa4dd30 ip : dfa4dd30 fp : dfa4dd54 r10: 82b16f40 r9 : 00000003 r8 : 840f7900 r7 : dfa4dd90 r6 : 840f7900 r5 : 00000000 r4 : 00000000 r3 : fee04f27 r2 : 81e15484 r1 : 00000001 r0 : 813ab8c8 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85b840c0 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:1055 Register r4 information: NULL pointer Register r5 information: NULL pointer Register r6 information: slab kmalloc-192 start 840f7900 pointer offset 0 size 192 Register r7 information: 2-page vmalloc region starting at 0xdfa4c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r8 information: slab kmalloc-192 start 840f7900 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 0xdfa4c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdfa4c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.2.6537 (pid: 752, stack limit = 0xdfa4c000) Stack: (0xdfa4dd30 to 0xdfa4e000) dd20: 823fe6c8 840f7900 829cf9ac 829cf9ac dd40: 81e15944 840f7944 dfa4dd8c dfa4dd58 813a7cf4 813abaf0 200000c0 00000000 dd60: dfa4dd7c 200000c0 840f7900 b5403587 200000c0 85f29800 40946400 00000003 dd80: dfa4de4c dfa4dd90 813a3840 813a7bf8 656d6f63 705f6964 6f707261 00007472 dda0: 00000000 00004f27 00000009 00010000 000000ff 00000002 00000004 0000000c ddc0: 00000007 0000000a 00000100 00000005 00000001 fffffffe 00000031 00004006 dde0: 00000101 00000000 0801a449 00000003 40000004 00000089 0000caa3 000007ff de00: 20001e58 0000000b 00000e68 00000000 00000008 0000f9e8 00000000 fffffff8 de20: 00000000 28b82975 00000000 85a28600 840f7900 200000c0 200000c0 85f29800 de40: dfa4df14 dfa4de50 813a480c 813a374c 00000000 00000000 00000000 28b82975 de60: 00000000 00000000 8247054c 0000005f 83df6658 840f7930 8424800c 85f29800 de80: dfa4dee4 dfa4de90 80797a5c 8078ddc0 00000064 00000001 00000000 dfa4deac dea0: 8588b6d0 834ef880 00006400 0000000b dfa4dea0 00000000 00000000 28b82975 dec0: 85a28600 40946400 200000c0 200000c0 85a28600 00000003 dfa4def4 dfa4dee8 dee0: 80797b7c 28b82975 dfa4df14 40946400 00000000 85a28601 200000c0 85a28600 df00: 00000003 85f29800 dfa4dfa4 dfa4df18 8056cd80 813a423c ecac8b10 85f29800 df20: dfa4df3c dfa4df30 81a39d78 81a39c48 dfa4df54 dfa4df40 8025e490 8028ef64 df40: dfa4dfb0 40000000 dfa4df84 dfa4df58 802229ec 8025e44c 00000000 8281cddc df60: dfa4dfb0 0014c820 ecac8b10 80222940 00000000 28b82975 dfa4dfac 00000000 df80: 00000000 002f6308 00000036 8020029c 85f29800 00000036 00000000 dfa4dfa8 dfa0: 80200060 8056cc5c 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f6e0bc dfe0: 76f6dec0 76f6deb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813abae4>] (parport_attach) from [<813a7cf4>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r6:840f7944 r5:81e15944 r4:829cf9ac [<813a7bec>] (comedi_device_attach) from [<813a3840>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:85f29800 r7:200000c0 r6:b5403587 r5:840f7900 r4:200000c0 [<813a3740>] (do_devconfig_ioctl) from [<813a480c>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:85f29800 r7:200000c0 r6:200000c0 r5:840f7900 r4:85a28600 [<813a4230>] (comedi_unlocked_ioctl) from [<8056cd80>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a4230>] (comedi_unlocked_ioctl) from [<8056cd80>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a4230>] (comedi_unlocked_ioctl) from [<8056cd80>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a4230>] (comedi_unlocked_ioctl) from [<8056cd80>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:85f29800 r9:00000003 r8:85a28600 r7:200000c0 r6:85a28601 r5:00000000 r4:40946400 [<8056cc50>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa4dfa8 to 0xdfa4dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f6e0bc dfe0: 76f6dec0 76f6deb0 0001948c 001322c0 r10:00000036 r9:85f29800 r8:8020029c r7:00000036 r6:002f6308 r5:00000000 r4:00000000 Code: e596306c e3a04000 e7f33053 e2433612 (e5c34000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e596306c ldr r3, [r6, #108] @ 0x6c 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