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: 3765 Comm: syz.0.21 Not tainted syzkaller #0 PREEMPT 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 : [<814162f4>] lr : [<814162e0>] psr: 60000013 sp : e0169cb0 ip : e0169cb0 fp : e0169ccc r10: 00000001 r9 : 00000084 r8 : e0169d9c r7 : 00004f27 r6 : 0000009b r5 : 845fd3c0 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 845fd3c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85e64500 DAC: fffffffd Register r0 information: slab kmalloc-192 start 845fd3c0 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 845fd3c0 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 0xe0168000 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 0xe0168000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Register r12 information: 2-page vmalloc region starting at 0xe0168000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2651 Process syz.0.21 (pid: 3765, stack limit = 0xe0168000) Stack: (0xe0169cb0 to 0xe016a000) 9ca0: 81416294 845fd3c0 00004f27 00004f27 9cc0: e0169cec e0169cd0 81415fcc 814162a0 00004f27 805150e4 85146000 85146000 9ce0: e0169d0c e0169cf0 8141638c 81415f80 845fd3c0 00000000 85146000 00004f27 9d00: e0169d4c e0169d10 81416538 8141630c 8280ca60 833d4600 828215b0 00000000 9d20: 00000000 829d46e0 845fd3c0 845fd404 e0169d88 845fd3c0 00000000 82b28ad8 9d40: e0169d84 e0169d50 8140506c 814164d0 845fd3f0 00000000 e0169d74 200000c0 9d60: 845fd3c0 b5403587 845fd3f0 8598ec00 40946400 00000003 e0169e44 e0169d88 9d80: 814009c4 81404f70 35353238 00000000 00000000 00000000 00000000 00004f27 9da0: 0000000a 00000005 00000016 00000005 00000005 00000006 000000f8 0000000e 9dc0: 000000fd 00000002 ffffffff fffffffe 00000001 00000004 00000005 fffffbff 9de0: 0000007f 00000000 40000003 00000089 00000003 00000003 20001e58 00000008 9e00: 00000e66 00000003 00000004 00000000 00000d75 fffffffb 00000000 6a2cf02a 9e20: 00000000 85d49cc0 845fd3c0 200000c0 845fd3f0 8598ec00 e0169f14 e0169e48 9e40: 814019b8 814008d0 00000000 00000000 00000000 00000000 00000000 6a2cf02a 9e60: 00000000 00000000 824a45ec 0000005f 844e0250 00000064 846225ac 8598ec00 9e80: e0169ee4 e0169e90 807b81b8 807ae6dc 00000064 00000001 00000000 e0169eac 9ea0: 85d96c10 834e3198 00006400 0000000b e0169ea0 00000000 00000000 6a2cf02a 9ec0: 85d49cc0 40946400 200000c0 200000c0 85d49cc0 00000003 e0169ef4 e0169ee8 9ee0: 807b82d8 6a2cf02a e0169f14 40946400 00000000 85d49cc1 200000c0 85d49cc0 9f00: 00000003 8598ec00 e0169fa4 e0169f18 805857a0 81401408 ecac8b10 8598ec00 9f20: e0169f3c e0169f30 81ab01ec 81ab00bc e0169f54 e0169f40 8025bcbc 8028e0c4 9f40: e0169fb0 40000000 e0169f84 e0169f58 80221a38 8025bc78 00000000 8281cf7c 9f60: e0169fb0 0014c8c0 ecac8b10 8022198c 00000000 6a2cf02a e0169fac 00000000 9f80: 00000000 00326310 00000036 8020029c 8598ec00 00000036 00000000 e0169fa8 9fa0: 80200060 8058567c 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fc70bc 9fe0: 76fc6ec0 76fc6eb0 000192bc 00132360 60000010 00000003 00000000 00000000 Call trace: [<81416294>] (subdev_8255_io) from [<81415fcc>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:845fd3c0 r4:81416294 [<81415f74>] (subdev_8255_do_config) from [<8141638c>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<81415f74>] (subdev_8255_do_config) from [<8141638c>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85146000 [<81416300>] (subdev_8255_io_init) from [<81416538>] (dev_8255_attach drivers/comedi/drivers/8255.c:82 [inline]) [<81416300>] (subdev_8255_io_init) from [<81416538>] (dev_8255_attach+0x74/0x120 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:85146000 r5:00000000 r4:845fd3c0 [<814164c4>] (dev_8255_attach) from [<8140506c>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1069) r10:82b28ad8 r9:00000000 r8:845fd3c0 r7:e0169d88 r6:845fd404 r5:845fd3c0 r4:829d46e0 [<81404f64>] (comedi_device_attach) from [<814009c4>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:928) r10:00000003 r9:40946400 r8:8598ec00 r7:845fd3f0 r6:b5403587 r5:845fd3c0 r4:200000c0 [<814008c4>] (do_devconfig_ioctl) from [<814019b8>] (comedi_unlocked_ioctl+0x5bc/0x1c2c drivers/comedi/comedi_fops.c:2240) r8:8598ec00 r7:845fd3f0 r6:200000c0 r5:845fd3c0 r4:85d49cc0 [<814013fc>] (comedi_unlocked_ioctl) from [<805857a0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<814013fc>] (comedi_unlocked_ioctl) from [<805857a0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<814013fc>] (comedi_unlocked_ioctl) from [<805857a0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<814013fc>] (comedi_unlocked_ioctl) from [<805857a0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8598ec00 r9:00000003 r8:85d49cc0 r7:200000c0 r6:85d49cc1 r5:00000000 r4:40946400 [<80585670>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xe0169fa8 to 0xe0169ff0) 9fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 9fc0: 00000000 00000000 00326310 00000036 00310000 00000000 00006364 76fc70bc 9fe0: 76fc6ec0 76fc6eb0 000192bc 00132360 r10:00000036 r9:8598ec00 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