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: 5123 Comm: syz.0.353 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 : e83cdcb8 ip : e83cdcb8 fp : e83cdcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 840cd540 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 840cd540 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85741bc0 DAC: 00000000 Register r0 information: slab kmalloc-192 start 840cd540 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 840cd540 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 0xe83cc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xe83cc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.0.353 (pid: 5123, stack limit = 0xe83cc000) Stack: (0xe83cdcb8 to 0xe83ce000) dca0: 813db538 840cd540 dcc0: 00004f27 00004f27 e83cdcf4 e83cdcd8 813db270 813db544 00004f27 8050a430 dce0: 850dc000 850dc000 e83cdd14 e83cdcf8 813db630 813db224 850dc000 840cd540 dd00: e83cdda4 00004f27 e83cdd54 e83cdd18 813db824 813db5b0 82af1fe0 85923980 dd20: 828215f0 00000000 00000000 829d238c 840cd540 840cd584 e83cdd90 840cd540 dd40: 00000000 82b25910 e83cdd8c e83cdd58 813ca720 813db774 200000c0 00000000 dd60: e83cdd7c 200000c0 840cd540 b5403587 200000c0 851e1800 40946400 00000003 dd80: e83cde4c e83cdd90 813c626c 813ca624 35353238 00000000 00000000 00000000 dda0: 00000000 00004f27 00000007 fffffffc fffffffe 0000ffff 00040cc7 00000008 ddc0: 00000009 0000000a 00000004 00000002 00000001 00000009 00000001 000009aa dde0: 00000009 00000001 0001a449 00000003 40000003 00000089 ffffffff 00000f27 de00: 00009ee7 0000000b 00000e69 0000003c 00000008 00010003 00000000 fffffff8 de20: 00000000 4cd4ebe4 00000000 859bd6c0 840cd540 200000c0 200000c0 851e1800 de40: e83cdf14 e83cde50 813c7238 813c6178 00000000 00000000 00000000 4cd4ebe4 de60: 00000000 00000000 824625b4 0000005f 83c98e20 840cd570 841ca564 851e1800 de80: e83cdee4 e83cde90 807a7684 8079da7c 00000064 00000001 00000000 e83cdeac dea0: 85235f10 834273b8 00006400 0000000b e83cdea0 00000000 00000000 4cd4ebe4 dec0: 859bd6c0 40946400 200000c0 200000c0 859bd6c0 00000003 e83cdef4 e83cdee8 dee0: 807a77a4 4cd4ebe4 e83cdf14 40946400 00000000 859bd6c1 200000c0 859bd6c0 df00: 00000003 851e1800 e83cdfa4 e83cdf18 805788b8 813c6c68 ecac8b10 851e1800 df20: e83cdf3c e83cdf30 81a60ab8 81a60988 e83cdf54 e83cdf40 8025c484 8028d914 df40: e83cdfb0 40000000 e83cdf84 e83cdf58 802229ec 8025c440 00000000 8281cfb4 df60: e83cdfb0 0014ca70 ecac8b10 80222940 00000000 4cd4ebe4 e83cdfac 00000000 df80: 00000000 00316308 00000036 8020029c 851e1800 00000036 00000000 e83cdfa8 dfa0: 80200060 80578794 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fc50bc dfe0: 76fc4ec0 76fc4eb0 000195a4 00132510 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 r5:840cd540 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) r4:850dc000 [<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:e83cdda4 r5:840cd540 r4:850dc000 [<813db768>] (dev_8255_attach) from [<813ca720>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:840cd540 r7:e83cdd90 r6:840cd584 r5:840cd540 r4:829d238c [<813ca618>] (comedi_device_attach) from [<813c626c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:851e1800 r7:200000c0 r6:b5403587 r5:840cd540 r4:200000c0 [<813c616c>] (do_devconfig_ioctl) from [<813c7238>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:851e1800 r7:200000c0 r6:200000c0 r5:840cd540 r4:859bd6c0 [<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) r10:851e1800 r9:00000003 r8:859bd6c0 r7:200000c0 r6:859bd6c1 r5:00000000 r4:40946400 [<80578788>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe83cdfa8 to 0xe83cdff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fc50bc dfe0: 76fc4ec0 76fc4eb0 000195a4 00132510 r10:00000036 r9:851e1800 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