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: 8795 Comm: syz.3.1091 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 : [<813db598>] lr : [<813db584>] psr: 60000013 sp : dfa9dcb8 ip : dfa9dcb8 fp : dfa9dcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 8409cf00 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 8409cf00 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85861c00 DAC: 00000000 Register r0 information: slab kmalloc-192 start 8409cf00 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 8409cf00 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 0xdfa9c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfa9c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.3.1091 (pid: 8795, stack limit = 0xdfa9c000) Stack: (0xdfa9dcb8 to 0xdfa9e000) dca0: 813db538 8409cf00 dcc0: 00004f27 00004f27 dfa9dcf4 dfa9dcd8 813db270 813db544 00004f27 8050a430 dce0: 8966a800 8966a800 dfa9dd14 dfa9dcf8 813db630 813db224 8966a800 8409cf00 dd00: dfa9dda4 00004f27 dfa9dd54 dfa9dd18 813db824 813db5b0 82af1fe0 84846700 dd20: 828215f0 00000000 00000000 829d238c 8409cf00 8409cf44 dfa9dd90 8409cf00 dd40: 00000000 82b25910 dfa9dd8c dfa9dd58 813ca720 813db774 200000c0 00000000 dd60: dfa9dd7c 200000c0 8409cf00 b5403587 200000c0 83ab0c00 40946400 00000003 dd80: dfa9de4c dfa9dd90 813c626c 813ca624 35353238 00000000 00000000 00000000 dda0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff ddc0: 5c952399 00000005 000003ff 00000802 00000000 00000001 00000001 00000008 dde0: 0000e1cb 00000006 00000004 00000003 00000008 80000089 fffffffd 00000000 de00: fffffff5 4e56766d 00000003 0000003c 00000008 00000004 08000000 dffffffa de20: 00000000 76a46265 00000000 8335c000 8409cf00 200000c0 200000c0 83ab0c00 de40: dfa9df14 dfa9de50 813c7238 813c6178 00000000 00000000 00000000 76a46265 de60: 00000000 00000000 824625b4 0000005f 83c299f0 8409cf30 8413ef3c 83ab0c00 de80: dfa9dee4 dfa9de90 807a7684 8079da7c 00000064 00000001 00000000 dfa9deac dea0: 85872910 83428b28 00006400 0000000b dfa9dea0 00000000 00000000 76a46265 dec0: 8335c000 40946400 200000c0 200000c0 8335c000 00000003 dfa9def4 dfa9dee8 dee0: 807a77a4 76a46265 dfa9df14 40946400 00000000 8335c001 200000c0 8335c000 df00: 00000003 83ab0c00 dfa9dfa4 dfa9df18 805788b8 813c6c68 ecac8b10 83ab0c00 df20: dfa9df3c dfa9df30 81a60ab8 81a60988 dfa9df54 dfa9df40 8025c484 8028d914 df40: dfa9dfb0 40000000 dfa9df84 dfa9df58 802229ec 8025c440 00000000 8281cfb4 df60: dfa9dfb0 0014ced0 ecac8b10 80222940 00000000 76a46265 dfa9dfac 00000000 df80: 00000000 00316308 00000036 8020029c 83ab0c00 00000036 00000000 dfa9dfa8 dfa0: 80200060 80578794 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f040bc dfe0: 76f03ec0 76f03eb0 0001928c 00132970 60000010 00000003 00000000 00000000 Call trace: [<813db538>] (subdev_8255_io) from [<813db270>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:8409cf00 r4:813db538 [<813db218>] (subdev_8255_do_config) from [<813db630>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db218>] (subdev_8255_do_config) from [<813db630>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:8966a800 [<813db5a4>] (subdev_8255_io_init) from [<813db824>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db5a4>] (subdev_8255_io_init) from [<813db824>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfa9dda4 r5:8409cf00 r4:8966a800 [<813db768>] (dev_8255_attach) from [<813ca720>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:8409cf00 r7:dfa9dd90 r6:8409cf44 r5:8409cf00 r4:829d238c [<813ca618>] (comedi_device_attach) from [<813c626c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83ab0c00 r7:200000c0 r6:b5403587 r5:8409cf00 r4:200000c0 [<813c616c>] (do_devconfig_ioctl) from [<813c7238>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83ab0c00 r7:200000c0 r6:200000c0 r5:8409cf00 r4:8335c000 [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83ab0c00 r9:00000003 r8:8335c000 r7:200000c0 r6:8335c001 r5:00000000 r4:40946400 [<80578788>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa9dfa8 to 0xdfa9dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f040bc dfe0: 76f03ec0 76f03eb0 0001928c 00132970 r10:00000036 r9:83ab0c00 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