8<--- cut here --- Unable to handle kernel paging request at virtual address fee00006 when write [fee00006] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 11383 Comm: syz.1.10145 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 : eb94dcb8 ip : eb94dcb8 fp : eb94dcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00000003 r6 : 0000009b r5 : 841ca9c0 r4 : 00000006 r3 : 0000009b r2 : fee00006 r1 : 00000001 r0 : 841ca9c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 855a6280 DAC: 00000000 Register r0 information: slab kmalloc-192 start 841ca9c0 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 841ca9c0 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 0xeb94c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xeb94c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.1.10145 (pid: 11383, stack limit = 0xeb94c000) Stack: (0xeb94dcb8 to 0xeb94e000) dca0: 813db538 841ca9c0 dcc0: 00000003 00000003 eb94dcf4 eb94dcd8 813db270 813db544 00000003 8050a430 dce0: 84dea800 84dea800 eb94dd14 eb94dcf8 813db630 813db224 84dea800 841ca9c0 dd00: eb94dda4 00000003 eb94dd54 eb94dd18 813db824 813db5b0 eb94dd3c eb94dd28 dd20: 81a649e8 00000000 813c6244 829d238c 841ca9c0 841caa04 eb94dd90 841ca9c0 dd40: 00000000 82b25910 eb94dd8c eb94dd58 813ca720 813db774 b5403587 00000000 dd60: 84183000 200002c0 841ca9c0 b5403587 200002c0 84183000 40946400 00000000 dd80: eb94de4c eb94dd90 813c626c 813ca624 35353238 00000000 00000000 00000000 dda0: 00000000 00000003 fdfffffd 00000003 00000005 0000002f 0000000a 00000007 ddc0: 00000005 00000ffe 00000001 00000000 00008500 00001003 0000000f 0000ffff dde0: 0000ffff ffffffa8 7ffffffd 000003ff 00000001 00000010 00000000 0000000f de00: 00000005 0000746f 00000007 00000005 00000003 00000000 fffffffe 00008049 de20: 00000000 3512c6a4 00000000 85a31d80 841ca9c0 200002c0 200002c0 84183000 de40: eb94df14 eb94de50 813c7238 813c6178 00000000 00000000 00000000 3512c6a4 de60: 00000000 00000000 824625b4 0000005f 83e30a30 841ca9f0 840e8684 84183000 de80: eb94dee4 eb94de90 807a7684 8079da7c 00000064 00000001 00000000 eb94deac dea0: 896d90d0 83430880 00006400 0000000b eb94dea0 00000000 eb94dd30 3512c6a4 dec0: 85a31d80 40946400 200002c0 200002c0 85a31d80 00000005 eb94def4 eb94dee8 dee0: 807a77a4 3512c6a4 eb94df14 40946400 00000000 85a31d81 200002c0 85a31d80 df00: 00000005 84183000 eb94dfa4 eb94df18 805788b8 813c6c68 ecac8b10 84183000 df20: eb94df3c eb94df30 81a60ab8 81a60988 eb94df54 eb94df40 8025c484 8028d914 df40: eb94dfb0 40000000 eb94df84 eb94df58 802229ec 8025c440 00000000 8281cfb4 df60: eb94dfb0 0014ca70 ecac8b10 80222940 00000000 3512c6a4 eb94dfac 00000000 df80: 00000000 00316308 00000036 8020029c 84183000 00000036 00000000 eb94dfa8 dfa0: 80200060 80578794 00000000 00000000 00000005 40946400 200002c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f800bc dfe0: 76f7fec0 76f7feb0 000195a4 00132510 60000010 00000005 00000000 00000000 Call trace: [<813db538>] (subdev_8255_io) from [<813db270>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000003 r6:00000003 r5:841ca9c0 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) r4:84dea800 [<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) r7:00000003 r6:eb94dda4 r5:841ca9c0 r4:84dea800 [<813db768>] (dev_8255_attach) from [<813ca720>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:841ca9c0 r7:eb94dd90 r6:841caa04 r5:841ca9c0 r4:829d238c [<813ca618>] (comedi_device_attach) from [<813c626c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000000 r9:40946400 r8:84183000 r7:200002c0 r6:b5403587 r5:841ca9c0 r4:200002c0 [<813c616c>] (do_devconfig_ioctl) from [<813c7238>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:84183000 r7:200002c0 r6:200002c0 r5:841ca9c0 r4:85a31d80 [<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) r10:84183000 r9:00000005 r8:85a31d80 r7:200002c0 r6:85a31d81 r5:00000000 r4:40946400 [<80578788>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xeb94dfa8 to 0xeb94dff0) dfa0: 00000000 00000000 00000005 40946400 200002c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f800bc dfe0: 76f7fec0 76f7feb0 000195a4 00132510 r10:00000036 r9:84183000 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