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: 0 UID: 0 PID: 8652 Comm: syz.4.1009 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 : [<8140e660>] lr : [<8140e64c>] psr: 60000013 sp : dfd59cb8 ip : dfd59cb8 fp : dfd59cd4 r10: 00000000 r9 : 00000084 r8 : dfd59da4 r7 : 00008001 r6 : 0000009b r5 : 845d9000 r4 : 00008004 r3 : 0000009b r2 : fee08004 r1 : 00000001 r0 : 845d9000 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85d12380 DAC: fffffffd Register r0 information: slab kmalloc-192 start 845d9000 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 845d9000 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 0xdfd58000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2651 Register r9 information: non-paged memory Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xdfd58000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xdfd58000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2651 Process syz.4.1009 (pid: 8652, stack limit = 0xdfd58000) Stack: (0xdfd59cb8 to 0xdfd5a000) 9ca0: 8140e600 00008001 9cc0: 845d9000 00008001 dfd59cf4 dfd59cd8 8140e33c 8140e60c 00008001 80516350 9ce0: 86134780 86134780 dfd59d14 dfd59cf8 8140e6f4 8140e2f0 845d9000 00000000 9d00: 86134780 00008001 dfd59d54 dfd59d18 8140e8a4 8140e678 82b137fc 853eb380 9d20: 828215f0 00000000 00000000 829d4c84 845d9000 00000000 dfd59d90 845d9000 9d40: 00000000 82b29b30 dfd59d8c dfd59d58 813fd298 8140e83c 40946400 00000000 9d60: dfd59d7c 200000c0 845d9000 b5403587 40946400 87fd9800 00000003 845d9030 9d80: dfd59e4c dfd59d90 813f8bd0 813fd198 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 d6f2a9ac 00000000 85da3480 845d9000 200000c0 40946400 87fd9800 9e40: dfd59f14 dfd59e50 813f9750 813f8b08 00000000 d6f2a9ac 00000000 00000000 9e60: 824b1574 dfd59ea4 0000005f 840cc838 00000064 845ba204 dfd59ee4 dfd59e88 9e80: 807b43fc 807aaa78 00000064 00000001 00000000 dfd59ea4 874ef250 83435880 9ea0: 00006400 0000000b dfd59e98 00000000 00000000 d6f2a9ac 00000000 85da3480 9ec0: 40946400 200000c0 200000c0 85da3480 00000003 87fd9800 dfd59ef4 dfd59ee8 9ee0: 807b452c d6f2a9ac dfd59f14 00000000 85da3481 40946400 200000c0 85da3480 9f00: 00000003 87fd9800 dfd59fa4 dfd59f18 80582358 813f9658 ecac8b10 87fd9800 9f20: dfd59f3c dfd59f30 81aa745c 81aa732c dfd59f54 dfd59f40 8025ba7c 8028ef68 9f40: dfd59fb0 40000000 dfd59f84 dfd59f58 80221a54 8025ba38 00000000 8281cfbc 9f60: dfd59fb0 0013ddc0 ecac8b10 802219a8 00000000 d6f2a9ac dfd59fac 00000000 9f80: 00000000 00346310 00000036 8020029c 87fd9800 00000036 00000000 dfd59fa8 9fa0: 80200060 80582120 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f670dc 9fe0: 76f66e88 76f66e78 00018734 0012fc20 60000010 00000003 00000000 00000000 Call trace: [<8140e600>] (subdev_8255_io) from [<8140e33c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00008001 r6:845d9000 r5:00008001 r4:8140e600 [<8140e2e4>] (subdev_8255_do_config) from [<8140e6f4>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8140e2e4>] (subdev_8255_do_config) from [<8140e6f4>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:86134780 [<8140e66c>] (subdev_8255_io_init) from [<8140e8a4>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<8140e66c>] (subdev_8255_io_init) from [<8140e8a4>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00008001 r6:86134780 r5:00000000 r4:845d9000 [<8140e830>] (dev_8255_attach) from [<813fd298>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b29b30 r9:00000000 r8:845d9000 r7:dfd59d90 r6:00000000 r5:845d9000 r4:829d4c84 [<813fd18c>] (comedi_device_attach) from [<813f8bd0>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:845d9030 r9:00000003 r8:87fd9800 r7:40946400 r6:b5403587 r5:845d9000 r4:200000c0 [<813f8afc>] (do_devconfig_ioctl) from [<813f9750>] (comedi_unlocked_ioctl+0x104/0x1c80 drivers/comedi/comedi_fops.c:2240) r8:87fd9800 r7:40946400 r6:200000c0 r5:845d9000 r4:85da3480 [<813f964c>] (comedi_unlocked_ioctl) from [<80582358>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813f964c>] (comedi_unlocked_ioctl) from [<80582358>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813f964c>] (comedi_unlocked_ioctl) from [<80582358>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813f964c>] (comedi_unlocked_ioctl) from [<80582358>] (sys_ioctl+0x244/0xb58 fs/ioctl.c:583) r10:87fd9800 r9:00000003 r8:85da3480 r7:200000c0 r6:40946400 r5:85da3481 r4:00000000 [<80582114>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfd59fa8 to 0xdfd59ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f670dc 9fe0: 76f66e88 76f66e78 00018734 0012fc20 r10:00000036 r9:87fd9800 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