8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f3a when write [fee04f3a] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 7116 Comm: syz.4.492 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP 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 : [<81417944>] lr : [<81417930>] psr: 60000013 sp : df9ddcb0 ip : df9ddcb0 fp : df9ddccc r10: 00000001 r9 : 00000084 r8 : df9ddd9c r7 : 00004f37 r6 : 0000009b r5 : 8445ad80 r4 : 00004f3a r3 : 0000009b r2 : fee04f3a r1 : 00000001 r0 : 8445ad80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 832cda00 DAC: 00000000 Register r0 information: slab kmalloc-192 start 8445ad80 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 8445ad80 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: 2-page vmalloc region starting at 0xdf9dc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdf9dc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdf9dc000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.4.492 (pid: 7116, stack limit = 0xdf9dc000) Stack: (0xdf9ddcb0 to 0xdf9de000) dca0: 814178e4 8445ad80 00004f37 00004f37 dcc0: df9ddcec df9ddcd0 8141761c 814178f0 00004f37 80515900 858c4000 858c4000 dce0: df9ddd0c df9ddcf0 814179dc 814175d0 8445ad80 00000000 858c4000 00004f37 dd00: df9ddd4c df9ddd10 81417b88 8141795c 8280ca60 85362000 828215b0 00000000 dd20: 00000000 829d46a0 8445ad80 8445adc4 df9ddd88 8445ad80 00000000 82b28ad8 dd40: df9ddd84 df9ddd50 814066bc 81417b20 8445adb0 00000000 df9ddd74 200000c0 dd60: 8445ad80 b5403587 8445adb0 873b0c00 40946400 00000003 df9dde44 df9ddd88 dd80: 81402014 814065c0 35353238 00000000 00000000 00000000 00000000 00004f37 dda0: 00000005 00000002 00000401 00000001 00000cc7 00000fff 5c95239d 00000005 ddc0: 000003ff 00000802 00001600 00000001 00000001 00000009 0000e1cb 20000006 dde0: 00000004 00000003 00000395 40000005 fffffffd 00000001 fffffff5 ffffeadd de00: 00000003 0000003a 00000008 00000004 08000000 dffffffa 00000000 6120ad1c de20: 00000000 87153c00 8445ad80 200000c0 8445adb0 873b0c00 df9ddf14 df9dde48 de40: 81403008 81401f20 00000000 00000000 00000000 00000000 00000000 6120ad1c de60: 00000000 00000000 824a45ec 0000005f 83fd8a30 00000064 845726cc 873b0c00 de80: df9ddee4 df9dde90 807b8b78 807af09c 00000064 00000001 00000000 df9ddeac dea0: 8714a790 83429198 00006400 0000000b df9ddea0 00000000 00000000 6120ad1c dec0: 87153c00 40946400 200000c0 200000c0 87153c00 00000003 df9ddef4 df9ddee8 dee0: 807b8c98 6120ad1c df9ddf14 40946400 00000000 87153c01 200000c0 87153c00 df00: 00000003 873b0c00 df9ddfa4 df9ddf18 805860e8 81402a58 ecac8b10 873b0c00 df20: df9ddf3c df9ddf30 81ab1b24 81ab19f4 df9ddf54 df9ddf40 8025bc80 8028e08c df40: df9ddfb0 40000000 df9ddf84 df9ddf58 80221a38 8025bc3c 00000000 8281cf7c df60: df9ddfb0 0014c8c0 ecac8b10 8022198c 00000000 6120ad1c df9ddfac 00000000 df80: 00000000 00326310 00000036 8020029c 873b0c00 00000036 00000000 df9ddfa8 dfa0: 80200060 80585fc4 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f0e0bc dfe0: 76f0dec0 76f0deb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<814178e4>] (subdev_8255_io) from [<8141761c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f37 r6:00004f37 r5:8445ad80 r4:814178e4 [<814175c4>] (subdev_8255_do_config) from [<814179dc>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814175c4>] (subdev_8255_do_config) from [<814179dc>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:858c4000 [<81417950>] (subdev_8255_io_init) from [<81417b88>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81417950>] (subdev_8255_io_init) from [<81417b88>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f37 r6:858c4000 r5:00000000 r4:8445ad80 [<81417b14>] (dev_8255_attach) from [<814066bc>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:8445ad80 r7:df9ddd88 r6:8445adc4 r5:8445ad80 r4:829d46a0 [<814065b4>] (comedi_device_attach) from [<81402014>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:873b0c00 r7:8445adb0 r6:b5403587 r5:8445ad80 r4:200000c0 [<81401f14>] (do_devconfig_ioctl) from [<81403008>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:873b0c00 r7:8445adb0 r6:200000c0 r5:8445ad80 r4:87153c00 [<81402a4c>] (comedi_unlocked_ioctl) from [<805860e8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81402a4c>] (comedi_unlocked_ioctl) from [<805860e8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81402a4c>] (comedi_unlocked_ioctl) from [<805860e8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81402a4c>] (comedi_unlocked_ioctl) from [<805860e8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:873b0c00 r9:00000003 r8:87153c00 r7:200000c0 r6:87153c01 r5:00000000 r4:40946400 [<80585fb8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdf9ddfa8 to 0xdf9ddff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f0e0bc dfe0: 76f0dec0 76f0deb0 000192bc 00132360 r10:00000036 r9:873b0c00 r8:8020029c r7:00000036 r6:00326310 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