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: 7722 Comm: syz.0.1158 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 : [<813db5b0>] lr : [<813db59c>] psr: 60000013 sp : dfb4dcb8 ip : dfb4dcb8 fp : dfb4dcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 842260c0 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 842260c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85a0fd40 DAC: 00000000 Register r0 information: slab kmalloc-192 start 842260c0 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 842260c0 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 0xdfb4c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfb4c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.0.1158 (pid: 7722, stack limit = 0xdfb4c000) Stack: (0xdfb4dcb8 to 0xdfb4e000) dca0: 813db550 842260c0 dcc0: 00004f27 00004f27 dfb4dcf4 dfb4dcd8 813db288 813db55c 00004f27 8050a430 dce0: 8499a000 8499a000 dfb4dd14 dfb4dcf8 813db648 813db23c 8499a000 842260c0 dd00: dfb4dda4 00004f27 dfb4dd54 dfb4dd18 813db83c 813db5c8 82af1fe0 83ffa100 dd20: 828215f0 00000000 00000000 829d238c 842260c0 84226104 dfb4dd90 842260c0 dd40: 00000000 82b25910 dfb4dd8c dfb4dd58 813ca738 813db78c 200000c0 00000000 dd60: dfb4dd7c 200000c0 842260c0 b5403587 200000c0 865b6c00 40946400 00000003 dd80: dfb4de4c dfb4dd90 813c6284 813ca63c 35353238 00000000 00000000 00000000 dda0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff ddc0: 5c952399 00000005 00000401 00000802 00001600 00000001 00000001 00000009 dde0: 0000e1cb 00000006 00000004 00000003 00000395 fffffffe fffffffd 00000000 de00: fffffff5 ffffeadb 00000003 0000003c 00000008 00000004 08000000 dffffffa de20: 00000000 a5340e0b 00000000 856ed780 842260c0 200000c0 200000c0 865b6c00 de40: dfb4df14 dfb4de50 813c7250 813c6190 00000000 00000000 00000000 a5340e0b de60: 00000000 00000000 824625b4 0000005f 83c58a30 842260f0 8420187c 865b6c00 de80: dfb4dee4 dfb4de90 807a7684 8079da7c 00000064 00000001 00000000 dfb4deac dea0: 85a4b790 83432a18 00006400 0000000b dfb4dea0 00000000 00000000 a5340e0b dec0: 856ed780 40946400 200000c0 200000c0 856ed780 00000003 dfb4def4 dfb4dee8 dee0: 807a77a4 a5340e0b dfb4df14 40946400 00000000 856ed781 200000c0 856ed780 df00: 00000003 865b6c00 dfb4dfa4 dfb4df18 805788b8 813c6c80 ecac8b10 865b6c00 df20: dfb4df3c dfb4df30 81a60ad8 81a609a8 dfb4df54 dfb4df40 8025c484 8028d914 df40: dfb4dfb0 40000000 dfb4df84 dfb4df58 802229ec 8025c440 00000000 8281cfb4 df60: dfb4dfb0 0014ced0 ecac8b10 80222940 00000000 a5340e0b dfb4dfac 00000000 df80: 00000000 00316308 00000036 8020029c 865b6c00 00000036 00000000 dfb4dfa8 dfa0: 80200060 80578794 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f7f0bc dfe0: 76f7eec0 76f7eeb0 0001928c 00132970 60000010 00000003 00000000 00000000 Call trace: [<813db550>] (subdev_8255_io) from [<813db288>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:842260c0 r4:813db550 [<813db230>] (subdev_8255_do_config) from [<813db648>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db230>] (subdev_8255_do_config) from [<813db648>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:8499a000 [<813db5bc>] (subdev_8255_io_init) from [<813db83c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db5bc>] (subdev_8255_io_init) from [<813db83c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfb4dda4 r5:842260c0 r4:8499a000 [<813db780>] (dev_8255_attach) from [<813ca738>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:842260c0 r7:dfb4dd90 r6:84226104 r5:842260c0 r4:829d238c [<813ca630>] (comedi_device_attach) from [<813c6284>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:865b6c00 r7:200000c0 r6:b5403587 r5:842260c0 r4:200000c0 [<813c6184>] (do_devconfig_ioctl) from [<813c7250>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:865b6c00 r7:200000c0 r6:200000c0 r5:842260c0 r4:856ed780 [<813c6c74>] (comedi_unlocked_ioctl) from [<805788b8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6c74>] (comedi_unlocked_ioctl) from [<805788b8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6c74>] (comedi_unlocked_ioctl) from [<805788b8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6c74>] (comedi_unlocked_ioctl) from [<805788b8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:865b6c00 r9:00000003 r8:856ed780 r7:200000c0 r6:856ed781 r5:00000000 r4:40946400 [<80578788>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb4dfa8 to 0xdfb4dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f7f0bc dfe0: 76f7eec0 76f7eeb0 0001928c 00132970 r10:00000036 r9:865b6c00 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