8<--- cut here --- Unable to handle kernel paging request at virtual address fee3ffc3 when write [fee3ffc3] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 4036 Comm: syz.2.17 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:99 [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 : [<814a3d5c>] lr : [<814a3d48>] psr: 60000013 sp : e8409cb8 ip : e8409cb8 fp : e8409cd4 r10: 0003ffc0 r9 : 00000004 r8 : e8409da4 r7 : 00000000 r6 : 0000009b r5 : 8311b540 r4 : 0003ffc3 r3 : 0000009b r2 : fee3ffc3 r1 : 00000001 r0 : 8311b540 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85d2ff40 DAC: fffffffd Register r0 information: slab kmalloc-192 start 8311b540 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:1048 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 8311b540 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: NULL pointer Register r8 information: 2-page vmalloc region starting at 0xe8408000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xe8408000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r12 information: 2-page vmalloc region starting at 0xe8408000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Process syz.2.17 (pid: 4036, stack limit = 0xe8408000) Stack: (0xe8409cb8 to 0xe840a000) 9ca0: 814a3cfc 0003ffc0 9cc0: 8311b540 00000000 e8409cf4 e8409cd8 814a3a38 814a3d08 0003ffc0 80547708 9ce0: 85152800 85152800 e8409d14 e8409cf8 814a3df0 814a39ec 8311b540 00000000 9d00: 85152800 00000000 e8409d54 e8409d18 814a3fa0 814a3d74 ffffffff 00000004 9d20: 82a22dc0 00000000 00000000 82bd9660 8311b540 00000000 e8409d90 8311b540 9d40: 00000000 82d30eb4 e8409d8c e8409d58 81492928 814a3f38 40946400 00000000 9d60: e8409d7c 200000c0 8311b540 b5403587 40946400 00000001 00000003 84fb6200 9d80: e8409e4c e8409d90 8148e12c 8149282c 35353238 00000000 00000000 00000000 9da0: 00000000 0003ffc0 0000007f 80000001 00000000 0000000a 00000002 00000080 9dc0: 00000006 00000fff 000000fd 0000ffff 17fffffc 00000003 fffffff9 0010000b 9de0: 000000fd 00000004 0000007a 00400000 00000000 20000089 00000013 00000000 9e00: 00008001 00000021 ffffffff 00000007 00000003 04000000 00000040 0000eac6 9e20: 00000000 6ca36af8 00000000 8389db80 8311b540 200000c0 40946400 00000001 9e40: e8409f14 e8409e50 8148f454 8148e06c 00000000 6ca36af8 00000000 00000000 9e60: 8254a844 e8409ea4 0000005f 8461c058 00000064 8311b570 e8409ee4 e8409e88 9e80: 80807df4 807fe4ac 00000064 00000001 00000000 e8409ea4 85945e10 834f2440 9ea0: 00006400 0000000b e8409e98 00000000 00000000 6ca36af8 80358ebc 8389db80 9ec0: 40946400 200000c0 200000c0 8389db80 00000003 84fb6200 e8409ef4 e8409ee8 9ee0: 80807f28 6ca36af8 e8409f14 00000000 8389db80 40946400 200000c0 8389db80 9f00: 00000003 84fb6200 e8409fa4 e8409f18 805bc58c 8148f10c e8409f4c e8409f28 9f20: 803558e0 80358dd0 ffffffff 805047dc e8409f54 e8409f40 8025b7a8 00000004 9f40: e8409fa4 e8409f50 803561b4 80355758 00000000 00000004 ffffffff 80233ea0 9f60: 00000000 00000000 00000000 00000000 00000000 6ca36af8 e8409fac 00000000 9f80: 00000000 00356310 00000036 8020029c 84fb6200 00000036 00000000 e8409fa8 9fa0: 80200060 805bc354 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 003562d8 003562e4 9fe0: 7eeae798 7eeae788 00018fa0 001309d0 60000010 00000003 00000000 00000000 Call trace: [<814a3cfc>] (subdev_8255_io) from [<814a3a38>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:8311b540 r5:0003ffc0 r4:814a3cfc [<814a39e0>] (subdev_8255_do_config) from [<814a3df0>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814a39e0>] (subdev_8255_do_config) from [<814a3df0>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:85152800 [<814a3d68>] (subdev_8255_io_init) from [<814a3fa0>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<814a3d68>] (subdev_8255_io_init) from [<814a3fa0>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:85152800 r5:00000000 r4:8311b540 [<814a3f2c>] (dev_8255_attach) from [<81492928>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d30eb4 r9:00000000 r8:8311b540 r7:e8409d90 r6:00000000 r5:8311b540 r4:82bd9660 [<81492820>] (comedi_device_attach) from [<8148e12c>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:84fb6200 r9:00000003 r8:00000001 r7:40946400 r6:b5403587 r5:8311b540 r4:200000c0 [<8148e060>] (do_devconfig_ioctl) from [<8148f454>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000001 r7:40946400 r6:200000c0 r5:8311b540 r4:8389db80 [<8148f100>] (comedi_unlocked_ioctl) from [<805bc58c>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8148f100>] (comedi_unlocked_ioctl) from [<805bc58c>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8148f100>] (comedi_unlocked_ioctl) from [<805bc58c>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8148f100>] (comedi_unlocked_ioctl) from [<805bc58c>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:84fb6200 r9:00000003 r8:8389db80 r7:200000c0 r6:40946400 r5:8389db80 r4:00000000 [<805bc348>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe8409fa8 to 0xe8409ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 003562d8 003562e4 9fe0: 7eeae798 7eeae788 00018fa0 001309d0 r10:00000036 r9:84fb6200 r8:8020029c r7:00000036 r6:00356310 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