8<--- cut here --- Unable to handle kernel paging request at virtual address fee04f2c when write [fee04f2c] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 28423 Comm: syz.1.17820 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 : [<81415c6c>] lr : [<81415c58>] psr: 60000013 sp : e4329cb0 ip : e4329cb0 fp : e4329ccc r10: 00000001 r9 : 00000084 r8 : e4329d9c r7 : 00004f29 r6 : 0000009b r5 : 84588a80 r4 : 00004f2c r3 : 0000009b r2 : fee04f2c r1 : 00000001 r0 : 84588a80 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8599e4c0 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84588a80 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 84588a80 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 0xe4328000 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 0xe4328000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xe4328000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.1.17820 (pid: 28423, stack limit = 0xe4328000) Stack: (0xe4329cb0 to 0xe432a000) 9ca0: 81415c0c 84588a80 00004f29 00004f29 9cc0: e4329cec e4329cd0 81415944 81415c18 00004f29 80514fcc 85adf000 85adf000 9ce0: e4329d0c e4329cf0 81415d04 814158f8 84588a80 00000000 85adf000 00004f29 9d00: e4329d4c e4329d10 81415eb0 81415c84 8280cc60 844fbf00 828217b0 00000000 9d20: 00000000 829d46a0 84588a80 84588ac4 e4329d88 84588a80 00000000 82b28ad8 9d40: e4329d84 e4329d50 814049e0 81415e48 84588ab0 00000000 e4329d74 200000c0 9d60: 84588a80 b5403587 84588ab0 8620a400 40946400 00000003 e4329e44 e4329d88 9d80: 81400338 814048e4 35353238 00000000 00000000 00000000 00000000 00004f29 9da0: 00000005 00000003 00000004 00000001 0000000b 00000000 00000002 00000081 9dc0: fffffffc 00000002 fffffffe 00000001 00000001 00000061 00000101 00000008 9de0: 00400009 00000009 00000005 00000099 00000000 00000080 00000000 00000007 9e00: 02000e69 00000006 00080004 fffffffe 00000000 fffffff8 00000000 a70851aa 9e20: 00000000 861f3780 84588a80 200000c0 84588ab0 8620a400 e4329f14 e4329e48 9e40: 8140132c 81400244 00000000 00000000 00000000 00000000 00000000 a70851aa 9e60: 00000000 00000000 824a35ec 0000005f 8418d408 00000064 845b3cb4 8620a400 9e80: e4329ee4 e4329e90 807b7f80 807ae4a4 00000064 00000001 00000000 e4329eac 9ea0: 85957610 834d2908 00006400 0000000b e4329ea0 00000000 00000000 a70851aa 9ec0: 861f3780 40946400 200000c0 200000c0 861f3780 00000003 e4329ef4 e4329ee8 9ee0: 807b80a0 a70851aa e4329f14 40946400 00000000 861f3781 200000c0 861f3780 9f00: 00000003 8620a400 e4329fa4 e4329f18 80585608 81400d7c ecac8b10 8620a400 9f20: e4329f3c e4329f30 81aaf9ac 81aaf87c e4329f54 e4329f40 8025bcbc 8028e0c4 9f40: e4329fb0 40000000 e4329f84 e4329f58 80221a38 8025bc78 00000000 8281d17c 9f60: e4329fb0 0014c8c0 ecac8b10 8022198c 00000000 a70851aa e4329fac 00000000 9f80: 00000000 00326310 00000036 8020029c 8620a400 00000036 00000000 e4329fa8 9fa0: 80200060 805854e4 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f220bc 9fe0: 76f21ec0 76f21eb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<81415c0c>] (subdev_8255_io) from [<81415944>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f29 r6:00004f29 r5:84588a80 r4:81415c0c [<814158ec>] (subdev_8255_do_config) from [<81415d04>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814158ec>] (subdev_8255_do_config) from [<81415d04>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85adf000 [<81415c78>] (subdev_8255_io_init) from [<81415eb0>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81415c78>] (subdev_8255_io_init) from [<81415eb0>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f29 r6:85adf000 r5:00000000 r4:84588a80 [<81415e3c>] (dev_8255_attach) from [<814049e0>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:84588a80 r7:e4329d88 r6:84588ac4 r5:84588a80 r4:829d46a0 [<814048d8>] (comedi_device_attach) from [<81400338>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:8620a400 r7:84588ab0 r6:b5403587 r5:84588a80 r4:200000c0 [<81400238>] (do_devconfig_ioctl) from [<8140132c>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:8620a400 r7:84588ab0 r6:200000c0 r5:84588a80 r4:861f3780 [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81400d70>] (comedi_unlocked_ioctl) from [<80585608>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8620a400 r9:00000003 r8:861f3780 r7:200000c0 r6:861f3781 r5:00000000 r4:40946400 [<805854d8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe4329fa8 to 0xe4329ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76f220bc 9fe0: 76f21ec0 76f21eb0 000192bc 00132360 r10:00000036 r9:8620a400 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