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: 0 UID: 0 PID: 2733 Comm: syz.9.20919 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 : [<813b8b60>] lr : [<813b8b4c>] psr: 60000013 sp : df885cb8 ip : df885cb8 fp : df885cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 8420ba80 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 8420ba80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 845bbf40 DAC: fffffffd Register r0 information: slab kmalloc-192 start 8420ba80 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 8420ba80 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 0xdf884000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdf884000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.9.20919 (pid: 2733, stack limit = 0xdf884000) Stack: (0xdf885cb8 to 0xdf886000) 5ca0: 813b8b00 8420ba80 5cc0: 00004f27 00004f27 df885cf4 df885cd8 813b8838 813b8b0c 00004f27 80503b1c 5ce0: 868e1800 868e1800 df885d14 df885cf8 813b8bf8 813b87ec 868e1800 8420ba80 5d00: df885da4 00004f27 df885d54 df885d18 813b8dec 813b8b78 82ae3da0 842d9780 5d20: 828215b0 00000000 00000000 829d0144 8420ba80 8420bac4 df885d90 8420ba80 5d40: 00000000 82b16f40 df885d8c df885d58 813a7cf4 813b8d3c 200000c0 00000000 5d60: df885d7c 200000c0 8420ba80 b5403587 200000c0 83a96c00 40946400 00000003 5d80: df885e4c df885d90 813a3840 813a7bf8 35353238 00000000 00000000 00000000 5da0: 00000000 00004f27 00000005 00000002 00000421 00000001 00000cc7 7fffffff 5dc0: 5c952399 80000005 000003ff 00000002 00000300 00000001 00000003 00000000 5de0: 00000000 00000000 00000008 fffffffa 000001ff 80000089 0000000a 00000000 5e00: 20001e54 ffffeada 00000003 0000003d 00000008 00000004 08000000 dffffffa 5e20: 00000000 782cfc94 00000000 8558f9c0 8420ba80 200000c0 200000c0 83a96c00 5e40: df885f14 df885e50 813a480c 813a374c 00000000 00000000 00000000 782cfc94 5e60: 00000000 00000000 8247054c 0000005f 83d2e258 8420bab0 83ee690c 83a96c00 5e80: df885ee4 df885e90 80797a5c 8078ddc0 00000064 00000001 00000000 df885eac 5ea0: 8480e910 834deb28 00006400 0000000b df885ea0 00000000 00000000 782cfc94 5ec0: 8558f9c0 40946400 200000c0 200000c0 8558f9c0 00000003 df885ef4 df885ee8 5ee0: 80797b7c 782cfc94 df885f14 40946400 00000000 8558f9c1 200000c0 8558f9c0 5f00: 00000003 83a96c00 df885fa4 df885f18 8056cd80 813a423c ecac8b10 83a96c00 5f20: df885f3c df885f30 81a39d78 81a39c48 df885f54 df885f40 8025e490 8028ef64 5f40: df885fb0 40000000 df885f84 df885f58 802229ec 8025e44c 00000000 8281cddc 5f60: df885fb0 0014c820 ecac8b10 80222940 00000000 782cfc94 df885fac 00000000 5f80: 00000000 002f6308 00000036 8020029c 83a96c00 00000036 00000000 df885fa8 5fa0: 80200060 8056cc5c 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f720bc 5fe0: 76f71ec0 76f71eb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813b8b00>] (subdev_8255_io) from [<813b8838>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:8420ba80 r4:813b8b00 [<813b87e0>] (subdev_8255_do_config) from [<813b8bf8>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813b87e0>] (subdev_8255_do_config) from [<813b8bf8>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:868e1800 [<813b8b6c>] (subdev_8255_io_init) from [<813b8dec>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813b8b6c>] (subdev_8255_io_init) from [<813b8dec>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:df885da4 r5:8420ba80 r4:868e1800 [<813b8d30>] (dev_8255_attach) from [<813a7cf4>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b16f40 r9:00000000 r8:8420ba80 r7:df885d90 r6:8420bac4 r5:8420ba80 r4:829d0144 [<813a7bec>] (comedi_device_attach) from [<813a3840>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83a96c00 r7:200000c0 r6:b5403587 r5:8420ba80 r4:200000c0 [<813a3740>] (do_devconfig_ioctl) from [<813a480c>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83a96c00 r7:200000c0 r6:200000c0 r5:8420ba80 r4:8558f9c0 [<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) r10:83a96c00 r9:00000003 r8:8558f9c0 r7:200000c0 r6:8558f9c1 r5:00000000 r4:40946400 [<8056cc50>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf885fa8 to 0xdf885ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76f720bc 5fe0: 76f71ec0 76f71eb0 0001948c 001322c0 r10:00000036 r9:83a96c00 r8:8020029c r7:00000036 r6:002f6308 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