8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2a when write [fee04f2a] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 10962 Comm: syz.4.1556 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 subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] PC is at subdev_8255_io+0x60/0x6c drivers/comedi/drivers/comedi_8255.c:43 LR is at subdev_8255_io drivers/comedi/drivers/comedi_8255.c:47 [inline] LR is at subdev_8255_io+0x4c/0x6c drivers/comedi/drivers/comedi_8255.c:43 pc : [<813de898>] lr : [<813de884>] psr: 60000013 sp : ea6adcb8 ip : ea6adcb8 fp : ea6adcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 840c5840 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 840c5840 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85da3580 DAC: 00000000 Register r0 information: slab kmalloc-192 start 840c5840 pointer offset 0 size 192 Register r1 information: non-paged memory Register r2 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1055 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 840c5840 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: non-paged memory Register r9 information: NULL pointer Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xea6ac000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xea6ac000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.4.1556 (pid: 10962, stack limit = 0xea6ac000) Stack: (0xea6adcb8 to 0xea6ae000) dca0: 813de838 840c5840 dcc0: 00004f27 00004f27 ea6adcf4 ea6adcd8 813de570 813de844 00004f27 8050cd3c dce0: 85e28000 85e28000 ea6add14 ea6adcf8 813de930 813de524 85e28000 840c5840 dd00: ea6adda4 00004f27 ea6add54 ea6add18 813deb24 813de8b0 82af2fa0 84d89f80 dd20: 828216f0 00000000 00000000 829d254c 840c5840 840c5884 ea6add90 840c5840 dd40: 00000000 82b268b8 ea6add8c ea6add58 813cda70 813dea74 200000c0 00000000 dd60: ea6add7c 200000c0 840c5840 b5403587 200000c0 84fb8c00 40946400 00000003 dd80: ea6ade4c ea6add90 813c95c8 813cd974 35353238 00000000 00000000 00000000 dda0: 00000000 00004f27 00000007 00000005 00000016 00000005 00000005 00000006 ddc0: 00000003 0000000e 000000fd 00000002 ffffffff 00000001 00000001 00000004 dde0: 00000005 fffffffe 0000007f 00000000 40000003 00000089 00000003 00000003 de00: 20001e58 00000009 00000e66 00400003 0995d000 00000000 00000000 fffffff8 de20: 00000000 94199209 00000000 84974d80 840c5840 200000c0 200000c0 84fb8c00 de40: ea6adf14 ea6ade50 813ca594 813c94d4 00000000 00000000 00000000 94199209 de60: 00000000 00000000 8249a5c4 0000005f 83c0f9f0 840c5870 840fc834 84fb8c00 de80: ea6adee4 ea6ade90 807ac200 807a295c 00000064 00000001 00000000 ea6adeac dea0: 84e0e610 8343a908 00006400 0000000b ea6adea0 00000000 00000000 94199209 dec0: 84974d80 40946400 200000c0 200000c0 84974d80 00000003 ea6adef4 ea6adee8 dee0: 807ac320 94199209 ea6adf14 40946400 00000000 84974d81 200000c0 84974d80 df00: 00000003 84fb8c00 ea6adfa4 ea6adf18 8057ca08 813c9fc4 ecac8b10 84fb8c00 df20: ea6adf3c ea6adf30 81a67044 81a66f14 ea6adf54 ea6adf40 8025c5c8 8028ecd4 df40: ea6adfb0 40000000 ea6adf84 ea6adf58 802229ec 8025c584 00000000 8281d0bc df60: ea6adfb0 0014cf70 ecac8b10 80222940 00000000 94199209 ea6adfac 00000000 df80: 00000000 00316308 00000036 8020029c 84fb8c00 00000036 00000000 ea6adfa8 dfa0: 80200060 8057c8e4 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f8e0bc dfe0: 76f8dec0 76f8deb0 00019294 00132a10 60000010 00000003 00000000 00000000 Call trace: [<813de838>] (subdev_8255_io) from [<813de570>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:840c5840 r4:813de838 [<813de518>] (subdev_8255_do_config) from [<813de930>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813de518>] (subdev_8255_do_config) from [<813de930>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85e28000 [<813de8a4>] (subdev_8255_io_init) from [<813deb24>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813de8a4>] (subdev_8255_io_init) from [<813deb24>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:ea6adda4 r5:840c5840 r4:85e28000 [<813dea68>] (dev_8255_attach) from [<813cda70>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b268b8 r9:00000000 r8:840c5840 r7:ea6add90 r6:840c5884 r5:840c5840 r4:829d254c [<813cd968>] (comedi_device_attach) from [<813c95c8>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:84fb8c00 r7:200000c0 r6:b5403587 r5:840c5840 r4:200000c0 [<813c94c8>] (do_devconfig_ioctl) from [<813ca594>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:84fb8c00 r7:200000c0 r6:200000c0 r5:840c5840 r4:84974d80 [<813c9fb8>] (comedi_unlocked_ioctl) from [<8057ca08>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c9fb8>] (comedi_unlocked_ioctl) from [<8057ca08>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c9fb8>] (comedi_unlocked_ioctl) from [<8057ca08>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c9fb8>] (comedi_unlocked_ioctl) from [<8057ca08>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:84fb8c00 r9:00000003 r8:84974d80 r7:200000c0 r6:84974d81 r5:00000000 r4:40946400 [<8057c8d8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xea6adfa8 to 0xea6adff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f8e0bc dfe0: 76f8dec0 76f8deb0 00019294 00132a10 r10:00000036 r9:84fb8c00 r8:8020029c r7:00000036 r6:00316308 r5:00000000 r4:00000000 Code: e6ef3076 e0842002 e7f32052 e2422612 (e5c23000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e6ef3076 uxtb r3, r6 4: e0842002 add r2, r4, r2 8: e7f32052 ubfx r2, r2, #0, #20 c: e2422612 sub r2, r2, #18874368 @ 0x1200000 * 10: e5c23000 strb r3, [r2] <-- trapping instruction