8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f29 when write [fee04f29] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 10301 Comm: syz.5.1261 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 : [<8143e4a8>] lr : [<8143e494>] psr: 60000013 sp : dfc4dcb8 ip : dfc4dcb8 fp : dfc4dcd4 r10: 00000000 r9 : 00000084 r8 : dfc4dda4 r7 : 00004f26 r6 : 0000009b r5 : 845e93c0 r4 : 00004f29 r3 : 0000009b r2 : fee04f29 r1 : 00000001 r0 : 845e93c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8517c440 DAC: 00000000 Register r0 information: slab kmalloc-192 start 845e93c0 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 845e93c0 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: 2-page vmalloc region starting at 0xdfc4c000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r9 information: non-paged memory Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xdfc4c000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r12 information: 2-page vmalloc region starting at 0xdfc4c000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Process syz.5.1261 (pid: 10301, stack limit = 0xdfc4c000) Stack: (0xdfc4dcb8 to 0xdfc4e000) dca0: 8143e448 00004f26 dcc0: 845e93c0 00004f26 dfc4dcf4 dfc4dcd8 8143e184 8143e454 00004f26 80522770 dce0: 862a9900 862a9900 dfc4dd14 dfc4dcf8 8143e53c 8143e138 845e93c0 00000000 dd00: 862a9900 00004f26 dfc4dd54 dfc4dd18 8143e6ec 8143e4c0 82b1699c 87251e00 dd20: 828217c0 00000000 00000000 829d6e04 845e93c0 00000000 dfc4dd90 845e93c0 dd40: 00000000 82b2efdc dfc4dd8c dfc4dd58 8142d030 8143e684 40946400 00000000 dd60: dfc4dd7c 200000c0 845e93c0 b5403587 40946400 00000001 00000003 84ffb000 dd80: dfc4de4c dfc4dd90 8142883c 8142cf30 35353238 00000000 00000000 00000000 dda0: 00000000 00004f26 00000000 00000002 00000401 00000001 00000cc7 00000fff ddc0: 5c952399 00000005 00000403 00000802 00001600 00000001 00000000 00000705 dde0: 0000e1cb 00000006 00000004 00000080 00000395 80001089 fffffffd 00000000 de00: fffffff5 ffffeadb 00000003 0040003e 00000008 00010000 08000000 00000002 de20: 00000000 0838cdc2 00000000 83366000 845e93c0 200000c0 40946400 00000001 de40: dfc4df14 dfc4de50 81429b60 81428774 00000000 0838cdc2 00000000 00000000 de60: 824b857c dfc4dea4 0000005f 84556058 00000064 845e93f0 dfc4dee4 dfc4de88 de80: 807cda48 807c3e20 00000064 00000001 00000000 dfc4dea4 86385190 8342e110 dea0: 00006400 0000000b dfc4de98 00000000 00000000 0838cdc2 00000000 83366000 dec0: 40946400 200000c0 200000c0 83366000 00000003 84ffb000 dfc4def4 dfc4dee8 dee0: 807cdb78 0838cdc2 dfc4df14 00000000 83366001 40946400 200000c0 83366000 df00: 00000003 84ffb000 dfc4dfa4 dfc4df18 8058f958 81429818 ecac8b10 84ffb000 df20: dfc4df3c dfc4df30 81ae1a14 81ae18e0 dfc4df54 dfc4df40 8025a868 8028c368 df40: dfc4dfb0 40000000 dfc4df84 dfc4df58 80220bf8 8025a824 00000000 8281d2bc df60: dfc4dfb0 0013e480 ecac8b10 80220b4c 00000000 0838cdc2 dfc4dfac 00000000 df80: 00000000 00346310 00000036 8020029c 84ffb000 00000036 00000000 dfc4dfa8 dfa0: 80200060 8058f720 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f170dc dfe0: 76f16e88 76f16e78 00018ba0 001302e0 60000010 00000003 00000000 00000000 Call trace: [<8143e448>] (subdev_8255_io) from [<8143e184>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f26 r6:845e93c0 r5:00004f26 r4:8143e448 [<8143e12c>] (subdev_8255_do_config) from [<8143e53c>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8143e12c>] (subdev_8255_do_config) from [<8143e53c>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:862a9900 [<8143e4b4>] (subdev_8255_io_init) from [<8143e6ec>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<8143e4b4>] (subdev_8255_io_init) from [<8143e6ec>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f26 r6:862a9900 r5:00000000 r4:845e93c0 [<8143e678>] (dev_8255_attach) from [<8142d030>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b2efdc r9:00000000 r8:845e93c0 r7:dfc4dd90 r6:00000000 r5:845e93c0 r4:829d6e04 [<8142cf24>] (comedi_device_attach) from [<8142883c>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:84ffb000 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:845e93c0 r4:200000c0 [<81428768>] (do_devconfig_ioctl) from [<81429b60>] (comedi_unlocked_ioctl+0x354/0x1dbc drivers/comedi/comedi_fops.c:2300) r8:00000001 r7:40946400 r6:200000c0 r5:845e93c0 r4:83366000 [<8142980c>] (comedi_unlocked_ioctl) from [<8058f958>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8142980c>] (comedi_unlocked_ioctl) from [<8058f958>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8142980c>] (comedi_unlocked_ioctl) from [<8058f958>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8142980c>] (comedi_unlocked_ioctl) from [<8058f958>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:84ffb000 r9:00000003 r8:83366000 r7:200000c0 r6:40946400 r5:83366001 r4:00000000 [<8058f714>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfc4dfa8 to 0xdfc4dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f170dc dfe0: 76f16e88 76f16e78 00018ba0 001302e0 r10:00000036 r9:84ffb000 r8:8020029c r7:00000036 r6:00346310 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