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: 6835 Comm: syz.0.839 Not tainted 6.17.0-rc1-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 : [<813b7dd0>] lr : [<813b7dbc>] psr: 60000013 sp : dfa3dcb8 ip : dfa3dcb8 fp : dfa3dcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 83e4ac00 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 83e4ac00 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85be4ec0 DAC: fffffffd Register r0 information: slab kmalloc-192 start 83e4ac00 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 83e4ac00 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 0xdfa3c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Register r12 information: 2-page vmalloc region starting at 0xdfa3c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2605 Process syz.0.839 (pid: 6835, stack limit = 0xdfa3c000) Stack: (0xdfa3dcb8 to 0xdfa3e000) dca0: 813b7d70 83e4ac00 dcc0: 00004f27 00004f27 dfa3dcf4 dfa3dcd8 813b7aa8 813b7d7c 00004f27 80503c30 dce0: 84f8a000 84f8a000 dfa3dd14 dfa3dcf8 813b7e68 813b7a5c 84f8a000 83e4ac00 dd00: dfa3dda4 00004f27 dfa3dd54 dfa3dd18 813b805c 813b7de8 82ae3d60 846c7880 dd20: 82821598 00000000 00000000 829d0084 83e4ac00 83e4ac44 dfa3dd90 83e4ac00 dd40: 00000000 82b16f00 dfa3dd8c dfa3dd58 813a6f60 813b7fac 200000c0 00000000 dd60: dfa3dd7c 200000c0 83e4ac00 b5403587 200000c0 838b3c00 40946400 00000003 dd80: dfa3de4c dfa3dd90 813a2ae0 813a6e64 35353238 00000000 00000000 00000000 dda0: 00000000 00004f27 00000005 00000002 00000401 00000001 00000cc7 00000fff ddc0: 5c952399 00000005 000003ff 00000802 00001600 00000001 00000001 00000009 dde0: 0000e1cb 00000006 00000004 00000003 00000000 80000089 fffffffd 00000000 de00: fffffff5 ffffeadb 00000003 0000003c 00000008 00000004 08000000 dffffffa de20: 00000000 1dfab46b 00000000 84848300 83e4ac00 200000c0 200000c0 838b3c00 de40: dfa3df14 dfa3de50 813a3aac 813a29ec 00000000 00000000 00000000 1dfab46b de60: 00000000 00000000 8247054c 0000005f 83d7f858 83e4ac30 84046b94 838b3c00 de80: dfa3dee4 dfa3de90 80797824 8078db88 00000064 00000001 00000000 dfa3deac dea0: 84827c10 835b5550 00006400 0000000b dfa3dea0 00000000 00000000 1dfab46b dec0: 84848300 40946400 200000c0 200000c0 84848300 00000003 dfa3def4 dfa3dee8 dee0: 80797944 1dfab46b dfa3df14 40946400 00000000 84848301 200000c0 84848300 df00: 00000003 838b3c00 dfa3dfa4 dfa3df18 8056cdf8 813a34dc ecac8b10 838b3c00 df20: dfa3df3c dfa3df30 81a38778 81a38648 dfa3df54 dfa3df40 8025e490 8028ef8c df40: dfa3dfb0 40000000 dfa3df84 dfa3df58 802229ec 8025e44c 00000000 8281cddc df60: dfa3dfb0 0014c820 ecac8b10 80222940 00000000 1dfab46b dfa3dfac 00000000 df80: 00000000 002f6308 00000036 8020029c 838b3c00 00000036 00000000 dfa3dfa8 dfa0: 80200060 8056ccd4 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76fff0bc dfe0: 76ffeec0 76ffeeb0 0001948c 001322c0 60000010 00000003 00000000 00000000 Call trace: [<813b7d70>] (subdev_8255_io) from [<813b7aa8>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:83e4ac00 r4:813b7d70 [<813b7a50>] (subdev_8255_do_config) from [<813b7e68>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813b7a50>] (subdev_8255_do_config) from [<813b7e68>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:84f8a000 [<813b7ddc>] (subdev_8255_io_init) from [<813b805c>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813b7ddc>] (subdev_8255_io_init) from [<813b805c>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfa3dda4 r5:83e4ac00 r4:84f8a000 [<813b7fa0>] (dev_8255_attach) from [<813a6f60>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1006) r10:82b16f00 r9:00000000 r8:83e4ac00 r7:dfa3dd90 r6:83e4ac44 r5:83e4ac00 r4:829d0084 [<813a6e58>] (comedi_device_attach) from [<813a2ae0>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:838b3c00 r7:200000c0 r6:b5403587 r5:83e4ac00 r4:200000c0 [<813a29e0>] (do_devconfig_ioctl) from [<813a3aac>] (comedi_unlocked_ioctl+0x5dc/0x1c24 drivers/comedi/comedi_fops.c:2173) r8:838b3c00 r7:200000c0 r6:200000c0 r5:83e4ac00 r4:84848300 [<813a34d0>] (comedi_unlocked_ioctl) from [<8056cdf8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813a34d0>] (comedi_unlocked_ioctl) from [<8056cdf8>] (do_vfs_ioctl fs/ioctl.c:552 [inline]) [<813a34d0>] (comedi_unlocked_ioctl) from [<8056cdf8>] (__do_sys_ioctl fs/ioctl.c:596 [inline]) [<813a34d0>] (comedi_unlocked_ioctl) from [<8056cdf8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:584) r10:838b3c00 r9:00000003 r8:84848300 r7:200000c0 r6:84848301 r5:00000000 r4:40946400 [<8056ccc8>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfa3dfa8 to 0xdfa3dff0) dfa0: 00000000 00000000 00000003 40946400 200000c0 00000000 dfc0: 00000000 00000000 002f6308 00000036 002e0000 00000000 00006364 76fff0bc dfe0: 76ffeec0 76ffeeb0 0001948c 001322c0 r10:00000036 r9:838b3c00 r8:8020029c r7:00000036 r6:002f6308 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