8<--- cut here --- Unable to handle kernel paging request at virtual address fee08004 when write [fee08004] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 13177 Comm: syz.4.2044 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 : [<813db398>] lr : [<813db384>] psr: 60000013 sp : df94dcb8 ip : df94dcb8 fp : df94dcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00008001 r6 : 0000009b r5 : 84151600 r4 : 00008004 r3 : 0000009b r2 : fee08004 r1 : 00000001 r0 : 84151600 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 84eb4100 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84151600 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 84151600 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 0xdf94c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdf94c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.4.2044 (pid: 13177, stack limit = 0xdf94c000) Stack: (0xdf94dcb8 to 0xdf94e000) dca0: 813db338 84151600 dcc0: 00008001 00008001 df94dcf4 df94dcd8 813db070 813db344 00008001 8050a54c dce0: 84fcb800 84fcb800 df94dd14 df94dcf8 813db430 813db024 84fcb800 84151600 dd00: df94dda4 00008001 df94dd54 df94dd18 813db624 813db3b0 8079d9dc 8416d400 dd20: 828215f0 00000000 00000000 829d238c 84151600 84151644 df94dd90 84151600 dd40: 00000000 82b25910 df94dd8c df94dd58 813ca520 813db574 200000c0 00000000 dd60: df94dd7c 200000c0 84151600 b5403587 200000c0 8321a400 40946400 00000003 dd80: df94de4c df94dd90 813c606c 813ca424 35353238 00000000 00000000 00000000 dda0: 00000000 00008001 00000002 00000001 00000007 00000004 00000cc9 00000008 ddc0: 000000ab 0000000a 00000100 00000000 00000001 00000005 00000007 00000006 dde0: 00007fff 00000001 0001a449 ffffffff 40000003 00000089 00000002 00000002 de00: 20001e58 00000115 00000008 0000003c 00000004 00000004 00000007 0000000d de20: 00000000 c78d07d4 00000000 848ec900 84151600 200000c0 200000c0 8321a400 de40: df94df14 df94de50 813c7038 813c5f78 00000000 df94de54 df94de54 c78d07d4 de60: 00000000 00000000 824625b4 0000005f 83e24058 84151630 83db2abc 8321a400 de80: df94dee4 df94de90 807a779c 8079db94 00000064 00000001 00000000 df94deac dea0: 85a3f0d0 834e5880 00006400 0000000b df94dea0 00000000 df94dd30 c78d07d4 dec0: 848ec900 40946400 200000c0 200000c0 848ec900 00000003 df94def4 df94dee8 dee0: 807a78bc c78d07d4 df94df14 40946400 00000000 848ec901 200000c0 848ec900 df00: 00000003 8321a400 df94dfa4 df94df18 805789d0 813c6a68 ecac8b10 8321a400 df20: df94df3c df94df30 81a608b8 81a60788 df94df54 df94df40 8025c484 8028d914 df40: df94dfb0 40000000 df94df84 df94df58 802229ec 8025c440 00000000 8281cfb4 df60: df94dfb0 0014ced0 ecac8b10 80222940 00000000 c78d07d4 df94dfac 00000000 df80: 00000000 00316308 00000036 8020029c 8321a400 00000036 00000000 df94dfa8 dfa0: 80200060 805788ac 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fc50bc dfe0: 76fc4ec0 76fc4eb0 0001928c 00132970 60000010 00000003 00000000 00000000 Call trace: [<813db338>] (subdev_8255_io) from [<813db070>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00008001 r6:00008001 r5:84151600 r4:813db338 [<813db018>] (subdev_8255_do_config) from [<813db430>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db018>] (subdev_8255_do_config) from [<813db430>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84fcb800 [<813db3a4>] (subdev_8255_io_init) from [<813db624>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db3a4>] (subdev_8255_io_init) from [<813db624>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00008001 r6:df94dda4 r5:84151600 r4:84fcb800 [<813db568>] (dev_8255_attach) from [<813ca520>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:84151600 r7:df94dd90 r6:84151644 r5:84151600 r4:829d238c [<813ca418>] (comedi_device_attach) from [<813c606c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:8321a400 r7:200000c0 r6:b5403587 r5:84151600 r4:200000c0 [<813c5f6c>] (do_devconfig_ioctl) from [<813c7038>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:8321a400 r7:200000c0 r6:200000c0 r5:84151600 r4:848ec900 [<813c6a5c>] (comedi_unlocked_ioctl) from [<805789d0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6a5c>] (comedi_unlocked_ioctl) from [<805789d0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6a5c>] (comedi_unlocked_ioctl) from [<805789d0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6a5c>] (comedi_unlocked_ioctl) from [<805789d0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8321a400 r9:00000003 r8:848ec900 r7:200000c0 r6:848ec901 r5:00000000 r4:40946400 [<805788a0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf94dfa8 to 0xdf94dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fc50bc dfe0: 76fc4ec0 76fc4eb0 0001928c 00132970 r10:00000036 r9:8321a400 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