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: 0 UID: 0 PID: 5870 Comm: syz.0.526 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 : [<8141719c>] lr : [<81417188>] psr: 60000013 sp : dfa91cb0 ip : dfa91cb0 fp : dfa91ccc r10: 00000001 r9 : 00000084 r8 : dfa91d9c r7 : 00004f27 r6 : 0000009b r5 : 8443a900 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 8443a900 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 86087800 DAC: fffffffd Register r0 information: slab kmalloc-192 start 8443a900 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 8443a900 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 0xdfa90000 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 0xdfa90000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfa90000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.0.526 (pid: 5870, stack limit = 0xdfa90000) Stack: (0xdfa91cb0 to 0xdfa92000) 1ca0: 8141713c 8443a900 00004f27 00004f27 1cc0: dfa91cec dfa91cd0 81416e74 81417148 00004f27 805153e4 85f67000 85f67000 1ce0: dfa91d0c dfa91cf0 81417234 81416e28 8443a900 00000000 85f67000 00004f27 1d00: dfa91d4c dfa91d10 814173e0 814171b4 8280ca60 8387ad00 828215b0 00000000 1d20: 00000000 829d46a0 8443a900 8443a944 dfa91d88 8443a900 00000000 82b28ad8 1d40: dfa91d84 dfa91d50 81405f14 81417378 8443a930 00000000 dfa91d74 20000180 1d60: 8443a900 b5403587 8443a930 845b8c00 40946400 00000003 dfa91e44 dfa91d88 1d80: 8140186c 81405e18 35353238 00000000 00000000 00000000 00000000 00004f27 1da0: 00000001 00000003 00000004 00000007 00000cc9 0000000f 00001007 0000000a 1dc0: fffffffc 00000002 00000003 fffffffe 00001001 00000007 00000101 0000000c 1de0: 0001a449 00000003 40000003 00000002 0000caa7 00000006 20001e58 00000007 1e00: 0000063e 0000013c 00000008 00000004 00000008 fffffff8 00000000 f9ec8fd9 1e20: 00000000 86233480 8443a900 20000180 8443a930 845b8c00 dfa91f14 dfa91e48 1e40: 81402860 81401778 00000000 00000000 00000000 00000000 00000000 f9ec8fd9 1e60: 00000000 00000000 824a45ec 0000005f 8462c250 00000064 845f8cb4 845b8c00 1e80: dfa91ee4 dfa91e90 807b85a8 807aeacc 00000064 00000001 00000000 dfa91eac 1ea0: 85fa39d0 8342e2a8 00006400 0000000b dfa91ea0 00000000 00000000 f9ec8fd9 1ec0: 86233480 40946400 20000180 20000180 86233480 00000003 dfa91ef4 dfa91ee8 1ee0: 807b86c8 f9ec8fd9 dfa91f14 40946400 00000000 86233481 20000180 86233480 1f00: 00000003 845b8c00 dfa91fa4 dfa91f18 80585b90 814022b0 ecac8b10 845b8c00 1f20: dfa91f3c dfa91f30 81ab1384 81ab1254 dfa91f54 dfa91f40 8025bcbc 8028e0c4 1f40: dfa91fb0 40000000 dfa91f84 dfa91f58 80221a38 8025bc78 00000000 8281cf7c 1f60: dfa91fb0 0014c8c0 ecac8b10 8022198c 00000000 f9ec8fd9 dfa91fac 00000000 1f80: 00000000 00326310 00000036 8020029c 845b8c00 00000036 00000000 dfa91fa8 1fa0: 80200060 80585a6c 00000000 00000000 00000003 40946400 20000180 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f880bc 1fe0: 76f87ec0 76f87eb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<8141713c>] (subdev_8255_io) from [<81416e74>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:8443a900 r4:8141713c [<81416e1c>] (subdev_8255_do_config) from [<81417234>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81416e1c>] (subdev_8255_do_config) from [<81417234>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85f67000 [<814171a8>] (subdev_8255_io_init) from [<814173e0>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<814171a8>] (subdev_8255_io_init) from [<814173e0>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:85f67000 r5:00000000 r4:8443a900 [<8141736c>] (dev_8255_attach) from [<81405f14>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:8443a900 r7:dfa91d88 r6:8443a944 r5:8443a900 r4:829d46a0 [<81405e0c>] (comedi_device_attach) from [<8140186c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:845b8c00 r7:8443a930 r6:b5403587 r5:8443a900 r4:20000180 [<8140176c>] (do_devconfig_ioctl) from [<81402860>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:845b8c00 r7:8443a930 r6:20000180 r5:8443a900 r4:86233480 [<814022a4>] (comedi_unlocked_ioctl) from [<80585b90>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814022a4>] (comedi_unlocked_ioctl) from [<80585b90>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814022a4>] (comedi_unlocked_ioctl) from [<80585b90>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814022a4>] (comedi_unlocked_ioctl) from [<80585b90>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:845b8c00 r9:00000003 r8:86233480 r7:20000180 r6:86233481 r5:00000000 r4:40946400 [<80585a60>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa91fa8 to 0xdfa91ff0) 1fa0: 00000000 00000000 00000003 40946400 20000180 00000000 1fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f880bc 1fe0: 76f87ec0 76f87eb0 000192bc 00132360 r10:00000036 r9:845b8c00 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