8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2a when write [fee04f2a] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 6107 Comm: syz.2.412 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 : [<813dbda0>] lr : [<813dbd8c>] psr: 60000013 sp : dfbfdcb8 ip : dfbfdcb8 fp : dfbfdcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 84023cc0 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 84023cc0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 84dc7480 DAC: 00000000 Register r0 information: slab kmalloc-192 start 84023cc0 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 84023cc0 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 0xdfbfc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfbfc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.2.412 (pid: 6107, stack limit = 0xdfbfc000) Stack: (0xdfbfdcb8 to 0xdfbfe000) dca0: 813dbd40 84023cc0 dcc0: 00004f27 00004f27 dfbfdcf4 dfbfdcd8 813dba78 813dbd4c 00004f27 8050a7ec dce0: 85765000 85765000 dfbfdd14 dfbfdcf8 813dbe38 813dba2c 85765000 84023cc0 dd00: dfbfdda4 00004f27 dfbfdd54 dfbfdd18 813dc02c 813dbdb8 82af1fe0 848f3a80 dd20: 828215f0 00000000 00000000 829d23cc 84023cc0 84023d04 dfbfdd90 84023cc0 dd40: 00000000 82b25910 dfbfdd8c dfbfdd58 813caf24 813dbf7c 20000180 00000000 dd60: dfbfdd7c 20000180 84023cc0 b5403587 20000180 856a5400 40946400 00000003 dd80: dfbfde4c dfbfdd90 813c6a70 813cae28 35353238 00000000 00000000 00000000 dda0: 00000000 00004f27 00000001 00000003 00000004 00000007 00000cc9 0000000f ddc0: 00001007 0000000a fffffffc 00000002 00000003 fffffffe 00001001 00000007 dde0: 00000101 0000000c 0001a449 00000003 40000003 00000002 0000caa7 00000006 de00: 20001e58 00000007 0000063e 0000013c 00000008 00000004 00000008 fffffff8 de20: 00000000 4523ef9e 00000000 848ff780 84023cc0 20000180 20000180 856a5400 de40: dfbfdf14 dfbfde50 813c7a3c 813c697c 00000000 00000000 00000000 4523ef9e de60: 00000000 00000000 824625b4 0000005f 83e0a640 84023cf0 84144b04 856a5400 de80: dfbfdee4 dfbfde90 807a7a38 8079e184 00000064 00000001 00000000 dfbfdeac dea0: 858090d0 834e3aa0 00006400 0000000b dfbfdea0 00000000 00000000 4523ef9e dec0: 848ff780 40946400 20000180 20000180 848ff780 00000003 dfbfdef4 dfbfdee8 dee0: 807a7b58 4523ef9e dfbfdf14 40946400 00000000 848ff781 20000180 848ff780 df00: 00000003 856a5400 dfbfdfa4 dfbfdf18 80578ef0 813c746c ecac8b10 856a5400 df20: dfbfdf3c dfbfdf30 81a618a0 81a61770 dfbfdf54 dfbfdf40 8025c484 8028d914 df40: dfbfdfb0 40000000 dfbfdf84 dfbfdf58 802229ec 8025c440 00000000 8281cfb4 df60: dfbfdfb0 0014ced0 ecac8b10 80222940 00000000 4523ef9e dfbfdfac 00000000 df80: 00000000 00316308 00000036 8020029c 856a5400 00000036 00000000 dfbfdfa8 dfa0: 80200060 80578dcc 00000000 00000000 00000003 40946400 20000180 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fe10bc dfe0: 76fe0ec0 76fe0eb0 00019294 00132970 60000010 00000003 00000000 00000000 Call trace: [<813dbd40>] (subdev_8255_io) from [<813dba78>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:84023cc0 r4:813dbd40 [<813dba20>] (subdev_8255_do_config) from [<813dbe38>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813dba20>] (subdev_8255_do_config) from [<813dbe38>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85765000 [<813dbdac>] (subdev_8255_io_init) from [<813dc02c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813dbdac>] (subdev_8255_io_init) from [<813dc02c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfbfdda4 r5:84023cc0 r4:85765000 [<813dbf70>] (dev_8255_attach) from [<813caf24>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:84023cc0 r7:dfbfdd90 r6:84023d04 r5:84023cc0 r4:829d23cc [<813cae1c>] (comedi_device_attach) from [<813c6a70>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:856a5400 r7:20000180 r6:b5403587 r5:84023cc0 r4:20000180 [<813c6970>] (do_devconfig_ioctl) from [<813c7a3c>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:856a5400 r7:20000180 r6:20000180 r5:84023cc0 r4:848ff780 [<813c7460>] (comedi_unlocked_ioctl) from [<80578ef0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c7460>] (comedi_unlocked_ioctl) from [<80578ef0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c7460>] (comedi_unlocked_ioctl) from [<80578ef0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c7460>] (comedi_unlocked_ioctl) from [<80578ef0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:856a5400 r9:00000003 r8:848ff780 r7:20000180 r6:848ff781 r5:00000000 r4:40946400 [<80578dc0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfbfdfa8 to 0xdfbfdff0) dfa0: 00000000 00000000 00000003 40946400 20000180 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fe10bc dfe0: 76fe0ec0 76fe0eb0 00019294 00132970 r10:00000036 r9:856a5400 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