8<--- cut here --- Unable to handle kernel paging request at virtual address fee00005 when write [fee00005] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 1 UID: 0 PID: 17357 Comm: syz.4.10788 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 : [<813dc260>] lr : [<813dc24c>] psr: 60000013 sp : dfb3dcb8 ip : dfb3dcb8 fp : dfb3dcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00000002 r6 : 0000009b r5 : 841896c0 r4 : 00000005 r3 : 0000009b r2 : fee00005 r1 : 00000001 r0 : 841896c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 84972a40 DAC: 00000000 Register r0 information: slab kmalloc-192 start 841896c0 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 841896c0 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 0xdfb3c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfb3c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.4.10788 (pid: 17357, stack limit = 0xdfb3c000) Stack: (0xdfb3dcb8 to 0xdfb3e000) dca0: 813dc200 841896c0 dcc0: 00000002 00000002 dfb3dcf4 dfb3dcd8 813dbf38 813dc20c 00000002 8050a85c dce0: 85254000 85254000 dfb3dd14 dfb3dcf8 813dc2f8 813dbeec 85254000 841896c0 dd00: dfb3dda4 00000002 dfb3dd54 dfb3dd18 813dc4ec 813dc278 82af1fe0 866c7880 dd20: 828215f0 00000000 00000000 829d240c 841896c0 84189704 dfb3dd90 841896c0 dd40: 00000000 82b25910 dfb3dd8c dfb3dd58 813cb3e8 813dc43c 20000180 00000000 dd60: dfb3dd7c 20000180 841896c0 b5403587 20000180 8330bc00 40946400 00000003 dd80: dfb3de4c dfb3dd90 813c6f34 813cb2ec 35353238 00000000 00000000 00000000 dda0: 00000000 00000002 0000000c 00000fff ffffbff9 00000005 00000cc5 0000000f ddc0: 00800007 0000000a 00000009 00000008 80000001 ffffbffd 00000005 fffffffe dde0: 00000007 00000004 00000040 000003fb 02000002 00000099 0000caa7 00008000 de00: 20001e57 00000007 00000e6b 0000003c 000000d0 fffffffe 00000001 00000fce de20: 00000000 6dabaa00 00000000 850c1cc0 841896c0 20000180 20000180 8330bc00 de40: dfb3df14 dfb3de50 813c7f00 813c6e40 00000000 00000000 00000000 6dabaa00 de60: 00000000 00000000 824625b4 0000005f 84114e20 841896f0 840d112c 8330bc00 de80: dfb3dee4 dfb3de90 807a7ab8 8079e204 00000064 00000001 00000000 dfb3deac dea0: 859e3910 8342f198 00006400 0000000b dfb3dea0 00000000 00000000 6dabaa00 dec0: 850c1cc0 40946400 20000180 20000180 850c1cc0 00000003 dfb3def4 dfb3dee8 dee0: 807a7bd8 6dabaa00 dfb3df14 40946400 00000000 850c1cc1 20000180 850c1cc0 df00: 00000003 8330bc00 dfb3dfa4 dfb3df18 80578f40 813c7930 ecac8b10 8330bc00 df20: dfb3df3c dfb3df30 81a61ce0 81a61bb0 dfb3df54 dfb3df40 8025c484 8028d914 df40: dfb3dfb0 40000000 dfb3df84 dfb3df58 802229ec 8025c440 00000000 8281cfb4 df60: dfb3dfb0 0014cf70 ecac8b10 80222940 00000000 6dabaa00 dfb3dfac 00000000 df80: 00000000 00316308 00000036 8020029c 8330bc00 00000036 00000000 dfb3dfa8 dfa0: 80200060 80578e1c 00000000 00000000 00000003 40946400 20000180 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fb50bc dfe0: 76fb4ec0 76fb4eb0 00019294 00132a10 60000010 00000003 00000000 00000000 Call trace: [<813dc200>] (subdev_8255_io) from [<813dbf38>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000002 r6:00000002 r5:841896c0 r4:813dc200 [<813dbee0>] (subdev_8255_do_config) from [<813dc2f8>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813dbee0>] (subdev_8255_do_config) from [<813dc2f8>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:85254000 [<813dc26c>] (subdev_8255_io_init) from [<813dc4ec>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813dc26c>] (subdev_8255_io_init) from [<813dc4ec>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00000002 r6:dfb3dda4 r5:841896c0 r4:85254000 [<813dc430>] (dev_8255_attach) from [<813cb3e8>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:841896c0 r7:dfb3dd90 r6:84189704 r5:841896c0 r4:829d240c [<813cb2e0>] (comedi_device_attach) from [<813c6f34>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:8330bc00 r7:20000180 r6:b5403587 r5:841896c0 r4:20000180 [<813c6e34>] (do_devconfig_ioctl) from [<813c7f00>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:8330bc00 r7:20000180 r6:20000180 r5:841896c0 r4:850c1cc0 [<813c7924>] (comedi_unlocked_ioctl) from [<80578f40>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c7924>] (comedi_unlocked_ioctl) from [<80578f40>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c7924>] (comedi_unlocked_ioctl) from [<80578f40>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c7924>] (comedi_unlocked_ioctl) from [<80578f40>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:8330bc00 r9:00000003 r8:850c1cc0 r7:20000180 r6:850c1cc1 r5:00000000 r4:40946400 [<80578e10>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb3dfa8 to 0xdfb3dff0) dfa0: 00000000 00000000 00000003 40946400 20000180 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76fb50bc dfe0: 76fb4ec0 76fb4eb0 00019294 00132a10 r10:00000036 r9:8330bc00 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