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: 21153 Comm: syz.4.3538 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 : [<8141c3e0>] lr : [<8141c3cc>] psr: 60000013 sp : e00d9cb8 ip : e00d9cb8 fp : e00d9cd4 r10: 00000000 r9 : 00000084 r8 : e00d9da4 r7 : 00004f27 r6 : 0000009b r5 : 833a0840 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 833a0840 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 869603c0 DAC: fffffffd Register r0 information: slab kmalloc-192 start 833a0840 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 833a0840 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 0xe00d8000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2654 Register r9 information: non-paged memory Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xe00d8000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2654 Register r12 information: 2-page vmalloc region starting at 0xe00d8000 allocated at kernel_clone+0xac/0x3f4 kernel/fork.c:2654 Process syz.4.3538 (pid: 21153, stack limit = 0xe00d8000) Stack: (0xe00d9cb8 to 0xe00da000) 9ca0: 8141c380 00004f27 9cc0: 833a0840 00004f27 e00d9cf4 e00d9cd8 8141c0bc 8141c38c 00004f27 80518988 9ce0: 85863000 85863000 e00d9d14 e00d9cf8 8141c474 8141c070 833a0840 00000000 9d00: 85863000 00004f27 e00d9d54 e00d9d18 8141c624 8141c3f8 82b06134 83ed7380 9d20: 82821780 00000000 00000000 829d6444 833a0840 00000000 e00d9d90 833a0840 9d40: 00000000 82b2df9c e00d9d8c e00d9d58 8140b014 8141c5bc 40946400 00000000 9d60: e00d9d7c 200000c0 833a0840 b5403587 40946400 87214800 00000003 833a0870 9d80: e00d9e4c e00d9d90 8140694c 8140af14 35353238 00000000 00000000 00000000 9da0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff 9dc0: 5c952399 00000005 000003ff 00000802 00001600 00000001 00000001 00000009 9de0: 0000e1cb 00000008 000000d4 00000003 00000000 00000000 0000d5f2 00000020 9e00: f7fffff5 ffffeadb ffffffff 0000003c 00000008 00000004 08000000 00000009 9e20: 00000000 ef87355b 00000000 860c83c0 833a0840 200000c0 40946400 87214800 9e40: e00d9f14 e00d9e50 814074cc 81406884 00000000 ef87355b 00000000 00000000 9e60: 824b457c e00d9ea4 0000005f 84156640 00000064 841daa2c e00d9ee4 e00d9e88 9e80: 807ba9a4 807b0d7c 00000064 00000001 00000000 e00d9ea4 86b37a90 834e0000 9ea0: 00006400 0000000b e00d9e98 00000000 00000000 ef87355b 00000000 860c83c0 9ec0: 40946400 200000c0 200000c0 860c83c0 00000003 87214800 e00d9ef4 e00d9ee8 9ee0: 807baad4 ef87355b e00d9f14 00000000 860c83c1 40946400 200000c0 860c83c0 9f00: 00000003 87214800 e00d9fa4 e00d9f18 80584f98 814073d4 ecac8b10 87214800 9f20: e00d9f3c e00d9f30 81ab95fc 81ab94c8 e00d9f54 e00d9f40 8025a030 8028d8bc 9f40: e00d9fb0 40000000 e00d9f84 e00d9f58 80220a4c 80259fec 00000000 8281d27c 9f60: e00d9fb0 0013ddc0 ecac8b10 802209a0 00000000 ef87355b e00d9fac 00000000 9f80: 00000000 00346310 00000036 8020029c 87214800 00000036 00000000 e00d9fa8 9fa0: 80200060 80584d60 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f160dc 9fe0: 76f15e88 76f15e78 00018734 0012fc20 60000010 00000003 00000000 00000000 Call trace: [<8141c380>] (subdev_8255_io) from [<8141c0bc>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:833a0840 r5:00004f27 r4:8141c380 [<8141c064>] (subdev_8255_do_config) from [<8141c474>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<8141c064>] (subdev_8255_do_config) from [<8141c474>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:85863000 [<8141c3ec>] (subdev_8255_io_init) from [<8141c624>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<8141c3ec>] (subdev_8255_io_init) from [<8141c624>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:85863000 r5:00000000 r4:833a0840 [<8141c5b0>] (dev_8255_attach) from [<8140b014>] (comedi_device_attach+0x10c/0x248 drivers/comedi/drivers.c:1069) r10:82b2df9c r9:00000000 r8:833a0840 r7:e00d9d90 r6:00000000 r5:833a0840 r4:829d6444 [<8140af08>] (comedi_device_attach) from [<8140694c>] (do_devconfig_ioctl+0xd4/0x21c drivers/comedi/comedi_fops.c:928) r10:833a0870 r9:00000003 r8:87214800 r7:40946400 r6:b5403587 r5:833a0840 r4:200000c0 [<81406878>] (do_devconfig_ioctl) from [<814074cc>] (comedi_unlocked_ioctl+0x104/0x1c80 drivers/comedi/comedi_fops.c:2240) r8:87214800 r7:40946400 r6:200000c0 r5:833a0840 r4:860c83c0 [<814073c8>] (comedi_unlocked_ioctl) from [<80584f98>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814073c8>] (comedi_unlocked_ioctl) from [<80584f98>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814073c8>] (comedi_unlocked_ioctl) from [<80584f98>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814073c8>] (comedi_unlocked_ioctl) from [<80584f98>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:87214800 r9:00000003 r8:860c83c0 r7:200000c0 r6:40946400 r5:860c83c1 r4:00000000 [<80584d54>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe00d9fa8 to 0xe00d9ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00346310 00000036 003462d8 00000000 00000001 76f160dc 9fe0: 76f15e88 76f15e78 00018734 0012fc20 r10:00000036 r9:87214800 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