8<--- cut here --- Unable to handle kernel paging request at virtual address fee08004 when write [fee08004] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 16577 Comm: syz.5.3077 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 : [<81436160>] lr : [<8143614c>] psr: 60000013 sp : e0349cb8 ip : e0349cb8 fp : e0349cd4 r10: 00000000 r9 : 00000084 r8 : e0349da4 r7 : 00008001 r6 : 0000009b r5 : 846d1840 r4 : 00008004 r3 : 0000009b r2 : fee08004 r1 : 00000001 r0 : 846d1840 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 852add40 DAC: 00000000 Register r0 information: slab kmalloc-192 start 846d1840 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 846d1840 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 0xe0348000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r9 information: non-paged memory Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xe0348000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Register r12 information: 2-page vmalloc region starting at 0xe0348000 allocated at kernel_clone+0xac/0x428 kernel/fork.c:2654 Process syz.5.3077 (pid: 16577, stack limit = 0xe0348000) Stack: (0xe0349cb8 to 0xe034a000) 9ca0: 81436100 00008001 9cc0: 846d1840 00008001 e0349cf4 e0349cd8 81435e3c 8143610c 00008001 805223ec 9ce0: 873513c0 873513c0 e0349d14 e0349cf8 814361f4 81435df0 846d1840 00000000 9d00: 873513c0 00008001 e0349d54 e0349d18 814363a4 81436178 82b15584 833e0700 9d20: 82821780 00000000 00000000 829d6504 846d1840 00000000 e0349d90 846d1840 9d40: 00000000 82b2df9c e0349d8c e0349d58 81424d90 8143633c 40946400 00000000 9d60: e0349d7c 200000c0 846d1840 b5403587 40946400 8397a400 00000003 846d1870 9d80: e0349e4c e0349d90 814206c8 81424c90 35353238 00000000 00000000 00000000 9da0: 00000000 00008001 00000000 00000001 00000000 00000001 00000001 00000004 9dc0: 0000000b 0000005c 000000fd 00001002 00000008 0000000b 00000800 00000006 9de0: ffffffff 00000003 00000400 00000002 40000003 00000089 00000002 00000f27 9e00: 00000006 00000007 10000008 0000000f 00000008 00000004 0000fffe fffffff8 9e20: 00000000 6053bfdd 00000000 861dac00 846d1840 200000c0 40946400 8397a400 9e40: e0349f14 e0349e50 81421248 81420600 00000000 6053bfdd 00000000 00000000 9e60: 824b557c e0349ea4 0000005f 847b3600 00000064 846fe24c e0349ee4 e0349e88 9e80: 807cb7cc 807c1ba4 00000064 00000001 00000000 e0349ea4 8609fc10 83438f68 9ea0: 00006400 0000000b e0349e98 00000000 00000000 6053bfdd 00000000 861dac00 9ec0: 40946400 200000c0 200000c0 861dac00 00000005 8397a400 e0349ef4 e0349ee8 9ee0: 807cb8fc 6053bfdd e0349f14 00000000 861dac01 40946400 200000c0 861dac00 9f00: 00000005 8397a400 e0349fa4 e0349f18 8058f558 81421150 ecac8b10 8397a400 9f20: e0349f3c e0349f30 81ad9274 81ad9140 e0349f54 e0349f40 8025a85c 8028bff0 9f40: e0349fb0 40000000 e0349f84 e0349f58 80220bf8 8025a818 00000000 8281d27c 9f60: e0349fb0 0013ddc0 ecac8b10 80220b4c 00000000 6053bfdd e0349fac 00000000 9f80: 00000000 00346310 00000036 8020029c 8397a400 00000036 00000000 e0349fa8 9fa0: 80200060 8058f320 00000000 00000000 00000005 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f340dc 9fe0: 76f33e88 76f33e78 00018734 0012fc20 60000010 00000005 00000000 00000000 Call trace: [<81436100>] (subdev_8255_io) from [<81435e3c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00008001 r6:846d1840 r5:00008001 r4:81436100 [<81435de4>] (subdev_8255_do_config) from [<814361f4>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81435de4>] (subdev_8255_do_config) from [<814361f4>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:873513c0 [<8143616c>] (subdev_8255_io_init) from [<814363a4>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<8143616c>] (subdev_8255_io_init) from [<814363a4>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00008001 r6:873513c0 r5:00000000 r4:846d1840 [<81436330>] (dev_8255_attach) from [<81424d90>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b2df9c r9:00000000 r8:846d1840 r7:e0349d90 r6:00000000 r5:846d1840 r4:829d6504 [<81424c84>] (comedi_device_attach) from [<814206c8>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:846d1870 r9:00000003 r8:8397a400 r7:40946400 r6:b5403587 r5:846d1840 r4:200000c0 [<814205f4>] (do_devconfig_ioctl) from [<81421248>] (comedi_unlocked_ioctl+0x104/0x1c80 drivers/comedi/comedi_fops.c:2240) r8:8397a400 r7:40946400 r6:200000c0 r5:846d1840 r4:861dac00 [<81421144>] (comedi_unlocked_ioctl) from [<8058f558>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81421144>] (comedi_unlocked_ioctl) from [<8058f558>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81421144>] (comedi_unlocked_ioctl) from [<8058f558>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81421144>] (comedi_unlocked_ioctl) from [<8058f558>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:8397a400 r9:00000005 r8:861dac00 r7:200000c0 r6:40946400 r5:861dac01 r4:00000000 [<8058f314>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe0349fa8 to 0xe0349ff0) 9fa0: 00000000 00000000 00000005 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f340dc 9fe0: 76f33e88 76f33e78 00018734 0012fc20 r10:00000036 r9:8397a400 r8:8020029c r7:00000036 r6:00346310 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