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: 6551 Comm: syz.1.507 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 : [<813db608>] lr : [<813db5f4>] psr: 60000013 sp : dfa31cb8 ip : dfa31cb8 fp : dfa31cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 84162cc0 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 84162cc0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8597f7c0 DAC: fffffffd Register r0 information: slab kmalloc-192 start 84162cc0 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 84162cc0 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: non-paged memory Register r8 information: non-paged memory Register r9 information: NULL pointer Register r10 information: NULL pointer Register r11 information: 2-page vmalloc region starting at 0xdfa30000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfa30000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.1.507 (pid: 6551, stack limit = 0xdfa30000) Stack: (0xdfa31cb8 to 0xdfa32000) 1ca0: 813db5a8 84162cc0 1cc0: 00004f27 00004f27 dfa31cf4 dfa31cd8 813db2e0 813db5b4 00004f27 8050a430 1ce0: 84f1f800 84f1f800 dfa31d14 dfa31cf8 813db6a0 813db294 84f1f800 84162cc0 1d00: dfa31da4 00004f27 dfa31d54 dfa31d18 813db894 813db620 82af1fe0 84065300 1d20: 828215f0 00000000 00000000 829d238c 84162cc0 84162d04 dfa31d90 84162cc0 1d40: 00000000 82b25910 dfa31d8c dfa31d58 813ca790 813db7e4 200000c0 00000000 1d60: dfa31d7c 200000c0 84162cc0 b5403587 200000c0 8563a400 40946400 00000003 1d80: dfa31e4c dfa31d90 813c62dc 813ca694 35353238 00000000 00000000 00000000 1da0: 00000000 00004f27 00000005 00000002 00000401 00000021 00000cc7 00000fff 1dc0: 5c952399 00000005 000003ff 00000000 00000005 00000001 00000000 00000009 1de0: 0000e1cb 00000004 00000004 00000003 00000395 80000089 00000002 00000000 1e00: 00000006 ffffeadb 00000003 80000000 00000008 80000001 08000000 00000005 1e20: 00000000 4e314f4a 00000000 84e66f00 84162cc0 200000c0 200000c0 8563a400 1e40: dfa31f14 dfa31e50 813c72a8 813c61e8 00000000 00000000 00000000 4e314f4a 1e60: 00000000 00000000 824625b4 0000005f 84202c28 84162cf0 84181cfc 8563a400 1e80: dfa31ee4 dfa31e90 807a7684 8079da7c 00000064 00000001 00000000 dfa31eac 1ea0: 84e63310 834337f8 00006400 0000000b dfa31ea0 00000000 00000000 4e314f4a 1ec0: 84e66f00 40946400 200000c0 200000c0 84e66f00 00000003 dfa31ef4 dfa31ee8 1ee0: 807a77a4 4e314f4a dfa31f14 40946400 00000000 84e66f01 200000c0 84e66f00 1f00: 00000003 8563a400 dfa31fa4 dfa31f18 805788b8 813c6cd8 ecac8b10 8563a400 1f20: dfa31f3c dfa31f30 81a60b38 81a60a08 dfa31f54 dfa31f40 8025c484 8028d914 1f40: dfa31fb0 40000000 dfa31f84 dfa31f58 802229ec 8025c440 00000000 8281cfb4 1f60: dfa31fb0 0014ced0 ecac8b10 80222940 00000000 4e314f4a dfa31fac 00000000 1f80: 00000000 00316308 00000036 8020029c 8563a400 00000036 00000000 dfa31fa8 1fa0: 80200060 80578794 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fdf0bc 1fe0: 76fdeec0 76fdeeb0 0001928c 00132970 60000010 00000003 00000000 00000000 Call trace: [<813db5a8>] (subdev_8255_io) from [<813db2e0>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:84162cc0 r4:813db5a8 [<813db288>] (subdev_8255_do_config) from [<813db6a0>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db288>] (subdev_8255_do_config) from [<813db6a0>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84f1f800 [<813db614>] (subdev_8255_io_init) from [<813db894>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db614>] (subdev_8255_io_init) from [<813db894>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfa31da4 r5:84162cc0 r4:84f1f800 [<813db7d8>] (dev_8255_attach) from [<813ca790>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:84162cc0 r7:dfa31d90 r6:84162d04 r5:84162cc0 r4:829d238c [<813ca688>] (comedi_device_attach) from [<813c62dc>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:8563a400 r7:200000c0 r6:b5403587 r5:84162cc0 r4:200000c0 [<813c61dc>] (do_devconfig_ioctl) from [<813c72a8>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:8563a400 r7:200000c0 r6:200000c0 r5:84162cc0 r4:84e66f00 [<813c6ccc>] (comedi_unlocked_ioctl) from [<805788b8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6ccc>] (comedi_unlocked_ioctl) from [<805788b8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6ccc>] (comedi_unlocked_ioctl) from [<805788b8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6ccc>] (comedi_unlocked_ioctl) from [<805788b8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8563a400 r9:00000003 r8:84e66f00 r7:200000c0 r6:84e66f01 r5:00000000 r4:40946400 [<80578788>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa31fa8 to 0xdfa31ff0) 1fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 1fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fdf0bc 1fe0: 76fdeec0 76fdeeb0 0001928c 00132970 r10:00000036 r9:8563a400 r8:8020029c r7:00000036 r6:00316308 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