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: 1 UID: 0 PID: 6080 Comm: syz.0.520 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 : [<813db3a0>] lr : [<813db38c>] psr: 60000013 sp : dfa95cb8 ip : dfa95cb8 fp : dfa95cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 83cd9600 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 83cd9600 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 848ba100 DAC: 00000000 Register r0 information: slab kmalloc-192 start 83cd9600 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 83cd9600 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 0xdfa94000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfa94000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.0.520 (pid: 6080, stack limit = 0xdfa94000) Stack: (0xdfa95cb8 to 0xdfa96000) 5ca0: 813db340 83cd9600 5cc0: 00004f27 00004f27 dfa95cf4 dfa95cd8 813db078 813db34c 00004f27 8050a310 5ce0: 84e5e000 84e5e000 dfa95d14 dfa95cf8 813db438 813db02c 84e5e000 83cd9600 5d00: dfa95da4 00004f27 dfa95d54 dfa95d18 813db62c 813db3b8 82af1fe0 838ade00 5d20: 828215f0 00000000 00000000 829d238c 83cd9600 83cd9644 dfa95d90 83cd9600 5d40: 00000000 82b25910 dfa95d8c dfa95d58 813ca528 813db57c 200000c0 00000000 5d60: dfa95d7c 200000c0 83cd9600 b5403587 200000c0 83c1bc00 40946400 00000003 5d80: dfa95e4c dfa95d90 813c6074 813ca42c 35353238 00000000 00000000 00000000 5da0: 00000000 00004f27 00000005 00000022 00000401 00000001 00006dc4 00000fff 5dc0: 5c95239c 00000005 000003ff 00000000 00000401 fffffffe 00000002 00000009 5de0: 0000e1cb 00000005 00000004 00000003 00000395 8000008b fffffffe 0000000a 5e00: fffffff5 00000001 00000003 00000000 00000000 00000004 08000000 dffffff9 5e20: 00000000 08c58c45 00000000 84a489c0 83cd9600 200000c0 200000c0 83c1bc00 5e40: dfa95f14 dfa95e50 813c7040 813c5f80 00000000 00000000 00000000 08c58c45 5e60: 00000000 00000000 824625b4 0000005f 83e84058 83cd9630 84139564 83c1bc00 5e80: dfa95ee4 dfa95e90 807a755c 8079d954 00000064 00000001 00000000 dfa95eac 5ea0: 8499bf10 8341d220 00006400 0000000b dfa95ea0 00000000 00000000 08c58c45 5ec0: 84a489c0 40946400 200000c0 200000c0 84a489c0 00000003 dfa95ef4 dfa95ee8 5ee0: 807a767c 08c58c45 dfa95f14 40946400 00000000 84a489c1 200000c0 84a489c0 5f00: 00000003 83c1bc00 dfa95fa4 dfa95f18 80578798 813c6a70 ecac8b10 83c1bc00 5f20: dfa95f3c dfa95f30 81a606d8 81a605a8 dfa95f54 dfa95f40 8025c484 8028d914 5f40: dfa95fb0 40000000 dfa95f84 dfa95f58 802229ec 8025c440 00000000 8281cfb4 5f60: dfa95fb0 0014ca70 ecac8b10 80222940 00000000 08c58c45 dfa95fac 00000000 5f80: 00000000 00316308 00000036 8020029c 83c1bc00 00000036 00000000 dfa95fa8 5fa0: 80200060 80578674 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f290bc 5fe0: 76f28ec0 76f28eb0 000195a4 00132510 60000010 00000003 00000000 00000000 Call trace: [<813db340>] (subdev_8255_io) from [<813db078>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:83cd9600 r4:813db340 [<813db020>] (subdev_8255_do_config) from [<813db438>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db020>] (subdev_8255_do_config) from [<813db438>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84e5e000 [<813db3ac>] (subdev_8255_io_init) from [<813db62c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db3ac>] (subdev_8255_io_init) from [<813db62c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfa95da4 r5:83cd9600 r4:84e5e000 [<813db570>] (dev_8255_attach) from [<813ca528>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:83cd9600 r7:dfa95d90 r6:83cd9644 r5:83cd9600 r4:829d238c [<813ca420>] (comedi_device_attach) from [<813c6074>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83c1bc00 r7:200000c0 r6:b5403587 r5:83cd9600 r4:200000c0 [<813c5f74>] (do_devconfig_ioctl) from [<813c7040>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83c1bc00 r7:200000c0 r6:200000c0 r5:83cd9600 r4:84a489c0 [<813c6a64>] (comedi_unlocked_ioctl) from [<80578798>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6a64>] (comedi_unlocked_ioctl) from [<80578798>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6a64>] (comedi_unlocked_ioctl) from [<80578798>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6a64>] (comedi_unlocked_ioctl) from [<80578798>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83c1bc00 r9:00000003 r8:84a489c0 r7:200000c0 r6:84a489c1 r5:00000000 r4:40946400 [<80578668>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa95fa8 to 0xdfa95ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f290bc 5fe0: 76f28ec0 76f28eb0 000195a4 00132510 r10:00000036 r9:83c1bc00 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