8<--- cut here --- Unable to handle kernel paging request at virtual address fee00404 when write [fee00404] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 10507 Comm: syz.8.1125 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 : [<81415ad4>] lr : [<81415ac0>] psr: 60000013 sp : e0089cb0 ip : e0089cb0 fp : e0089ccc r10: 00000001 r9 : 00000084 r8 : e0089d9c r7 : 00000401 r6 : 0000009b r5 : 845260c0 r4 : 00000404 r3 : 0000009b r2 : fee00404 r1 : 00000001 r0 : 845260c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85df2640 DAC: fffffffd Register r0 information: slab kmalloc-192 start 845260c0 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 845260c0 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 0xe0088000 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 0xe0088000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xe0088000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.8.1125 (pid: 10507, stack limit = 0xe0088000) Stack: (0xe0089cb0 to 0xe008a000) 9ca0: 81415a74 845260c0 00000401 00000401 9cc0: e0089cec e0089cd0 814157ac 81415a80 00000401 80514fb4 861fb800 861fb800 9ce0: e0089d0c e0089cf0 81415b6c 81415760 845260c0 00000000 861fb800 00000401 9d00: e0089d4c e0089d10 81415d18 81415aec 8280cc60 84781680 828217b0 00000000 9d20: 00000000 829d46a0 845260c0 84526104 e0089d88 845260c0 00000000 82b28ad8 9d40: e0089d84 e0089d50 81404848 81415cb0 845260f0 00000000 e0089d74 20000080 9d60: 845260c0 b5403587 845260f0 869a3c00 40946400 00000000 e0089e44 e0089d88 9d80: 814001a0 8140474c 35353238 00000000 00000000 00000000 00000000 00000401 9da0: 00000181 00000002 0000000b 14000000 00000000 fffffffc 00000002 00000ffd 9dc0: 00007ffe 00000003 00000723 00000400 00000180 00000013 00000100 ffffffa7 9de0: 00000009 0000134d 00000001 000003fd 04000009 00000007 0000e2df 00000005 9e00: 0000000f 00000004 00040000 00000007 00000f58 00000008 00000000 35c66824 9e20: 00000000 874b09c0 845260c0 20000080 845260f0 869a3c00 e0089f14 e0089e48 9e40: 81401194 814000ac 00000000 00000000 00000000 00000000 00000000 35c66824 9e60: 00000000 00000000 824a35ec 0000005f 84344250 00000064 84426d8c 869a3c00 9e80: e0089ee4 e0089e90 807b7f68 807ae48c 00000064 00000001 00000000 e0089eac 9ea0: 86809490 834efb28 00006400 0000000b e0089ea0 00000000 00000000 35c66824 9ec0: 874b09c0 40946400 20000080 20000080 874b09c0 00000003 e0089ef4 e0089ee8 9ee0: 807b8088 35c66824 e0089f14 40946400 00000000 874b09c1 20000080 874b09c0 9f00: 00000003 869a3c00 e0089fa4 e0089f18 805855f0 81400be4 ecac8b10 869a3c00 9f20: e0089f3c e0089f30 81aaf80c 81aaf6dc e0089f54 e0089f40 8025bcbc 8028e0c4 9f40: e0089fb0 40000000 e0089f84 e0089f58 80221a38 8025bc78 00000000 8281d17c 9f60: e0089fb0 0014c8c0 ecac8b10 8022198c 00000000 35c66824 e0089fac 00000000 9f80: 00000000 00326310 00000036 8020029c 869a3c00 00000036 00000000 e0089fa8 9fa0: 80200060 805854cc 00000000 00000000 00000003 40946400 20000080 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fc00bc 9fe0: 76fbfec0 76fbfeb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<81415a74>] (subdev_8255_io) from [<814157ac>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000401 r6:00000401 r5:845260c0 r4:81415a74 [<81415754>] (subdev_8255_do_config) from [<81415b6c>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81415754>] (subdev_8255_do_config) from [<81415b6c>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:861fb800 [<81415ae0>] (subdev_8255_io_init) from [<81415d18>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81415ae0>] (subdev_8255_io_init) from [<81415d18>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00000401 r6:861fb800 r5:00000000 r4:845260c0 [<81415ca4>] (dev_8255_attach) from [<81404848>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:845260c0 r7:e0089d88 r6:84526104 r5:845260c0 r4:829d46a0 [<81404740>] (comedi_device_attach) from [<814001a0>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000000 r9:40946400 r8:869a3c00 r7:845260f0 r6:b5403587 r5:845260c0 r4:20000080 [<814000a0>] (do_devconfig_ioctl) from [<81401194>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:869a3c00 r7:845260f0 r6:20000080 r5:845260c0 r4:874b09c0 [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<81400bd8>] (comedi_unlocked_ioctl) from [<805855f0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:869a3c00 r9:00000003 r8:874b09c0 r7:20000080 r6:874b09c1 r5:00000000 r4:40946400 [<805854c0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe0089fa8 to 0xe0089ff0) 9fa0: 00000000 00000000 00000003 40946400 20000080 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fc00bc 9fe0: 76fbfec0 76fbfeb0 000192bc 00132360 r10:00000036 r9:869a3c00 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