8<--- cut here --- Unable to handle kernel paging request at virtual address fee003c7 when write [fee003c7] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 16694 Comm: syz.4.2971 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 : [<814ad81c>] lr : [<814ad808>] psr: 60000013 sp : dfbadcb8 ip : dfbadcb8 fp : dfbadcd4 r10: 000003c4 r9 : 00000004 r8 : dfbadda4 r7 : 00000000 r6 : 0000009b r5 : 838550c0 r4 : 000003c7 r3 : 0000009b r2 : fee003c7 r1 : 00000001 r0 : 838550c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 867c9d80 DAC: 00000000 Register r0 information: slab kmalloc-192 start 838550c0 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 838550c0 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 0xdfbac000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2766 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfbac000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2766 Register r12 information: 2-page vmalloc region starting at 0xdfbac000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2766 Process syz.4.2971 (pid: 16694, stack limit = 0xdfbac000) Stack: (0xdfbadcb8 to 0xdfbae000) dca0: 814ad7bc 000003c4 dcc0: 838550c0 00000000 dfbadcf4 dfbadcd8 814ad4f8 814ad7c8 000003c4 80547798 dce0: 86967800 86967800 dfbadd14 dfbadcf8 814ad8b0 814ad4ac 838550c0 00000000 dd00: 86967800 00000000 dfbadd54 dfbadd18 814ada60 814ad834 ffffffff 00000004 dd20: 82a22dc0 00000000 00000000 82bdac60 838550c0 00000000 dfbadd90 838550c0 dd40: 00000000 82d32f9c dfbadd8c dfbadd58 8149c3e8 814ad9f8 40946400 00000000 dd60: dfbadd7c 20000080 838550c0 b5403587 40946400 00000003 00000003 83e53100 dd80: dfbade4c dfbadd90 81497bec 8149c2ec 35353238 00000000 00000000 00000000 dda0: 00000000 000003c4 00000004 00000002 0000000a 00000401 00000000 fffffffc ddc0: 00000040 00000ffd 00007ffe 00000003 00000006 00000400 00000000 00000013 dde0: 00000100 ffffffab 00000009 0000034d 00000001 000003ff 00007fff 00000006 de00: 0000e2df 0000aa14 00000001 00000004 00000027 00000007 0000000e 00000004 de20: 00000000 c74a85db 00000000 838b1b80 838550c0 20000080 40946400 00000003 de40: dfbadf14 dfbade50 81498f14 81497b2c 00000000 c74a85db 00000000 00000000 de60: 8254e844 dfbadea4 0000005f 848ea5e0 00000064 838550f0 dfbadee4 dfbade88 de80: 8080b76c 80801e24 00000064 00000001 00000000 dfbadea4 831e8110 834e6d48 dea0: 00006400 0000000b dfbade98 00000000 00000000 c74a85db 00000000 838b1b80 dec0: 40946400 20000080 20000080 838b1b80 00000003 83e53100 dfbadef4 dfbadee8 dee0: 8080b8a0 c74a85db dfbadf14 00000000 838b1b81 40946400 20000080 838b1b80 df00: 00000003 83e53100 dfbadfa4 dfbadf18 805bdf78 81498bcc ecac8b10 83e53100 df20: dfbadf3c dfbadf30 81b6ec00 81b6eacc dfbadf54 dfbadf40 8025b878 8028f548 df40: dfbadfb0 40000000 dfbadf84 dfbadf58 80221bdc 8025b834 00000000 82a1eb0c df60: dfbadfb0 0013ebf0 ecac8b10 80221b30 00000000 c74a85db dfbadfac 00000000 df80: 00000000 00356310 00000036 8020029c 83e53100 00000036 00000000 dfbadfa8 dfa0: 80200060 805bdd40 00000000 00000000 00000003 40946400 20000080 00000000 dfc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f5f0dc dfe0: 76f5ee88 76f5ee78 00018fa0 00130a50 60000010 00000003 00000000 00000000 Call trace: [<814ad7bc>] (subdev_8255_io) from [<814ad4f8>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:838550c0 r5:000003c4 r4:814ad7bc [<814ad4a0>] (subdev_8255_do_config) from [<814ad8b0>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814ad4a0>] (subdev_8255_do_config) from [<814ad8b0>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:86967800 [<814ad828>] (subdev_8255_io_init) from [<814ada60>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<814ad828>] (subdev_8255_io_init) from [<814ada60>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:86967800 r5:00000000 r4:838550c0 [<814ad9ec>] (dev_8255_attach) from [<8149c3e8>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d32f9c r9:00000000 r8:838550c0 r7:dfbadd90 r6:00000000 r5:838550c0 r4:82bdac60 [<8149c2e0>] (comedi_device_attach) from [<81497bec>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:83e53100 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:838550c0 r4:20000080 [<81497b20>] (do_devconfig_ioctl) from [<81498f14>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:20000080 r5:838550c0 r4:838b1b80 [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81498bc0>] (comedi_unlocked_ioctl) from [<805bdf78>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:83e53100 r9:00000003 r8:838b1b80 r7:20000080 r6:40946400 r5:838b1b81 r4:00000000 [<805bdd34>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfbadfa8 to 0xdfbadff0) dfa0: 00000000 00000000 00000003 40946400 20000080 00000000 dfc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f5f0dc dfe0: 76f5ee88 76f5ee78 00018fa0 00130a50 r10:00000036 r9:83e53100 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