8<--- cut here --- Unable to handle kernel paging request at virtual address fee00004 when write [fee00004] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 6503 Comm: syz.1.722 Not tainted 6.16.0-rc4-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 : [<813a5ad0>] lr : [<813a5abc>] psr: 60000013 sp : df9e5cc0 ip : df9e5cc0 fp : df9e5cdc r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00000001 r6 : 0000009b r5 : 83f8c900 r4 : 00000004 r3 : 0000009b r2 : fee00004 r1 : 00000001 r0 : 83f8c900 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8605df00 DAC: 00000000 Register r0 information: slab kmalloc-192 start 83f8c900 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 83f8c900 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 0xdf9e4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2599 Register r12 information: 2-page vmalloc region starting at 0xdf9e4000 allocated at kernel_clone+0xac/0x3e4 kernel/fork.c:2599 Process syz.1.722 (pid: 6503, stack limit = 0xdf9e4000) Stack: (0xdf9e5cc0 to 0xdf9e6000) 5cc0: 813a5a70 83f8c900 00000001 00000001 df9e5cfc df9e5ce0 813a57a8 813a5a7c 5ce0: 00000001 80508714 8493f000 8493f000 df9e5d1c df9e5d00 813a5b68 813a575c 5d00: 8493f000 83f8c900 df9e5dac 00000001 df9e5d5c df9e5d20 813a5d5c 813a5ae8 5d20: 20000013 83f4f300 82822670 00000000 00000000 829c52b0 83f8c900 00000000 5d40: df9e5d98 83f8c900 00000000 82b15078 df9e5d94 df9e5d60 81394c80 813a5cac 5d60: 20000140 00000000 df9e5d84 20000140 83f8c900 b5403587 20000140 85e0b000 5d80: 40946400 00000003 df9e5e4c df9e5d98 81390910 81394b88 35353238 00000000 5da0: 00000000 00000000 00000000 00000001 00002166 00000004 00100000 000088d6 5dc0: 0000008f fffffffd 00000006 01000002 ffffffff 00000200 0000000c 00000006 5de0: 00000001 00000007 00000007 00000008 00000003 00000003 00000004 00000100 5e00: 00000003 00000080 00000003 00000006 00000001 0000571f 000007db 00000008 5e20: 00000007 00000004 00000000 1c4ce65d 00000000 85c1f9c0 83f8c900 20000140 5e40: df9e5f14 df9e5e50 813918c4 81390844 00000000 00000000 00000000 1c4ce65d 5e60: 00000000 00000000 8246a3fc 0000005f 83e85e58 83f8c930 8421e09c 85e0b000 5e80: df9e5ee4 df9e5e90 8079688c 8078cb7c 00000064 00000001 00000000 df9e5eac 5ea0: 85c3c0d0 83431cc0 00006400 0000000b df9e5ea0 00000000 00000000 1c4ce65d 5ec0: 85c1f9c0 40946400 20000140 20000140 00000003 85c1f9c0 df9e5ef4 df9e5ee8 5ee0: 807969ac 1c4ce65d df9e5f14 40946400 00000000 85c1f9c1 20000140 00000003 5f00: 85c1f9c0 85e0b000 df9e5fa4 df9e5f18 8056f16c 813912f4 ecac8b10 85e0b000 5f20: df9e5f3c df9e5f30 81a2db88 81a2da58 df9e5f54 df9e5f40 8026203c 802935d8 5f40: df9e5fb0 40000000 df9e5f84 df9e5f58 802229ec 80261ff8 00000000 8281d09c 5f60: df9e5fb0 0014c4a0 ecac8b10 80222940 00000000 1c4ce65d df9e5fac 00000000 5f80: 00000000 002f6300 00000036 8020029c 85e0b000 00000036 00000000 df9e5fa8 5fa0: 80200060 8056f048 00000000 00000000 00000003 40946400 20000140 00000000 5fc0: 00000000 00000000 002f6300 00000036 002e0000 00000000 00006364 76bd00bc 5fe0: 76bcfec0 76bcfeb0 000193a4 00131f40 60000010 00000003 00000000 00000000 Call trace: [<813a5a70>] (subdev_8255_io) from [<813a57a8>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000001 r6:00000001 r5:83f8c900 r4:813a5a70 [<813a5750>] (subdev_8255_do_config) from [<813a5b68>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813a5750>] (subdev_8255_do_config) from [<813a5b68>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:8493f000 [<813a5adc>] (subdev_8255_io_init) from [<813a5d5c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813a5adc>] (subdev_8255_io_init) from [<813a5d5c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00000001 r6:df9e5dac r5:83f8c900 r4:8493f000 [<813a5ca0>] (dev_8255_attach) from [<81394c80>] (comedi_device_attach+0x104/0x240 drivers/comedi/drivers.c:996) r10:82b15078 r9:00000000 r8:83f8c900 r7:df9e5d98 r6:00000000 r5:83f8c900 r4:829c52b0 [<81394b7c>] (comedi_device_attach) from [<81390910>] (do_devconfig_ioctl+0xd8/0x1e0 drivers/comedi/comedi_fops.c:855) r10:00000003 r9:40946400 r8:85e0b000 r7:20000140 r6:b5403587 r5:83f8c900 r4:20000140 [<81390838>] (do_devconfig_ioctl) from [<813918c4>] (comedi_unlocked_ioctl+0x5dc/0x1b94 drivers/comedi/comedi_fops.c:2136) r6:20000140 r5:83f8c900 r4:85c1f9c0 [<813912e8>] (comedi_unlocked_ioctl) from [<8056f16c>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813912e8>] (comedi_unlocked_ioctl) from [<8056f16c>] (do_vfs_ioctl fs/ioctl.c:861 [inline]) [<813912e8>] (comedi_unlocked_ioctl) from [<8056f16c>] (__do_sys_ioctl fs/ioctl.c:905 [inline]) [<813912e8>] (comedi_unlocked_ioctl) from [<8056f16c>] (sys_ioctl+0x130/0xdc8 fs/ioctl.c:893) r10:85e0b000 r9:85c1f9c0 r8:00000003 r7:20000140 r6:85c1f9c1 r5:00000000 r4:40946400 [<8056f03c>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9e5fa8 to 0xdf9e5ff0) 5fa0: 00000000 00000000 00000003 40946400 20000140 00000000 5fc0: 00000000 00000000 002f6300 00000036 002e0000 00000000 00006364 76bd00bc 5fe0: 76bcfec0 76bcfeb0 000193a4 00131f40 r10:00000036 r9:85e0b000 r8:8020029c r7:00000036 r6:002f6300 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