8<--- cut here --- Unable to handle kernel paging request at virtual address fee0000b when write [fee0000b] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 11916 Comm: syz.1.1789 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 : df9d1cb8 ip : df9d1cb8 fp : df9d1cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00000008 r6 : 0000009b r5 : 83c87e40 r4 : 0000000b r3 : 0000009b r2 : fee0000b r1 : 00000001 r0 : 83c87e40 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 84946880 DAC: 00000000 Register r0 information: slab kmalloc-192 start 83c87e40 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 83c87e40 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 0xdf9d0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdf9d0000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.1.1789 (pid: 11916, stack limit = 0xdf9d0000) Stack: (0xdf9d1cb8 to 0xdf9d2000) 1ca0: 813db338 83c87e40 1cc0: 00000008 00000008 df9d1cf4 df9d1cd8 813db070 813db344 00000008 8050a54c 1ce0: 85385800 85385800 df9d1d14 df9d1cf8 813db430 813db024 85385800 83c87e40 1d00: df9d1da4 00000008 df9d1d54 df9d1d18 813db624 813db3b0 82af1fe0 84a88a80 1d20: 828215f0 00000000 00000000 829d238c 83c87e40 83c87e84 df9d1d90 83c87e40 1d40: 00000000 82b25910 df9d1d8c df9d1d58 813ca520 813db574 200000c0 00000000 1d60: df9d1d7c 200000c0 83c87e40 b5403587 200000c0 8418d400 40946400 00000003 1d80: df9d1e4c df9d1d90 813c606c 813ca424 35353238 00000000 00000000 00000000 1da0: 00000000 00000008 00010005 80000001 000f0084 0000000c 00000001 00000fff 1dc0: 5c95238c 0000000a 000003bf 00000802 000015fa 00000005 20000001 00000809 1de0: 00000000 fffffff9 00000007 00000002 00000000 00000008 00008004 0000000b 1e00: 00000001 fffffffb 00800003 000000ef 00000000 0008000a 08000003 dffffffd 1e20: 00000000 1e31f783 00000000 8588e3c0 83c87e40 200000c0 200000c0 8418d400 1e40: df9d1f14 df9d1e50 813c7038 813c5f78 00000000 00000000 00000000 1e31f783 1e60: 00000000 00000000 824625b4 0000005f 841fe448 83c87e70 84119cb4 8418d400 1e80: df9d1ee4 df9d1e90 807a779c 8079db94 00000064 00000001 00000000 df9d1eac 1ea0: 862d7b50 83427908 00006400 0000000b df9d1ea0 00000000 00000000 1e31f783 1ec0: 8588e3c0 40946400 200000c0 200000c0 8588e3c0 00000003 df9d1ef4 df9d1ee8 1ee0: 807a78bc 1e31f783 df9d1f14 40946400 00000000 8588e3c1 200000c0 8588e3c0 1f00: 00000003 8418d400 df9d1fa4 df9d1f18 805789d0 813c6a68 ecac8b10 8418d400 1f20: df9d1f3c df9d1f30 81a608b8 81a60788 df9d1f54 df9d1f40 8025c484 8028d914 1f40: df9d1fb0 40000000 df9d1f84 df9d1f58 802229ec 8025c440 00000000 8281cfb4 1f60: df9d1fb0 0014ced0 ecac8b10 80222940 00000000 1e31f783 df9d1fac 00000000 1f80: 00000000 00316308 00000036 8020029c 8418d400 00000036 00000000 df9d1fa8 1fa0: 80200060 805788ac 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f900bc 1fe0: 76f8fec0 76f8feb0 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) r7:00000008 r6:00000008 r5:83c87e40 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) r4:85385800 [<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) r7:00000008 r6:df9d1da4 r5:83c87e40 r4:85385800 [<813db568>] (dev_8255_attach) from [<813ca520>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:83c87e40 r7:df9d1d90 r6:83c87e84 r5:83c87e40 r4:829d238c [<813ca418>] (comedi_device_attach) from [<813c606c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:8418d400 r7:200000c0 r6:b5403587 r5:83c87e40 r4:200000c0 [<813c5f6c>] (do_devconfig_ioctl) from [<813c7038>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:8418d400 r7:200000c0 r6:200000c0 r5:83c87e40 r4:8588e3c0 [<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) r10:8418d400 r9:00000003 r8:8588e3c0 r7:200000c0 r6:8588e3c1 r5:00000000 r4:40946400 [<805788a0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9d1fa8 to 0xdf9d1ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f900bc 1fe0: 76f8fec0 76f8feb0 0001928c 00132970 r10:00000036 r9:8418d400 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