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: 10118 Comm: syz.6.1184 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 : [<813db598>] lr : [<813db584>] psr: 60000013 sp : dfab5cb8 ip : dfab5cb8 fp : dfab5cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 8402bf00 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 8402bf00 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 85ad3340 DAC: fffffffd Register r0 information: slab kmalloc-192 start 8402bf00 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 8402bf00 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 0xdfab4000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xdfab4000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.6.1184 (pid: 10118, stack limit = 0xdfab4000) Stack: (0xdfab5cb8 to 0xdfab6000) 5ca0: 813db538 8402bf00 5cc0: 00004f27 00004f27 dfab5cf4 dfab5cd8 813db270 813db544 00004f27 b5403587 5ce0: 8398b000 8398b000 dfab5d14 dfab5cf8 813db630 813db224 8398b000 8402bf00 5d00: dfab5da4 00004f27 dfab5d54 dfab5d18 813db824 813db5b0 82af1fe0 86e21880 5d20: 828215f0 00000000 00000000 829d238c 8402bf00 8402bf44 dfab5d90 8402bf00 5d40: 00000000 82b25910 dfab5d8c dfab5d58 813ca720 813db774 200000c0 00000000 5d60: dfab5d7c 200000c0 8402bf00 b5403587 200000c0 83a5b000 40946400 00000003 5d80: dfab5e4c dfab5d90 813c626c 813ca624 35353238 00000000 00000000 00000000 5da0: 00000000 00004f27 00000005 00000003 00000004 00000001 0000000c 00000007 5dc0: 00000004 0000000a 00000007 00000002 00000001 fffffffe 00000001 00000002 5de0: 00000101 00000004 00000009 00000003 0000352f 00000099 0000caa7 00000084 5e00: 20001e58 00000007 02000e67 0000001c 00000004 0000007f 00000000 fffffff8 5e20: 00000000 6904e4aa 00000000 849b9d80 8402bf00 200000c0 200000c0 83a5b000 5e40: dfab5f14 dfab5e50 813c7238 813c6178 00000000 00000000 00000000 6904e4aa 5e60: 00000000 00000000 824625b4 0000005f 83e5d408 8402bf30 84103a2c 83a5b000 5e80: dfab5ee4 dfab5e90 807a7684 8079da7c 00000064 00000001 00000000 dfab5eac 5ea0: 85b70910 83427000 00006400 0000000b dfab5ea0 00000000 00000000 6904e4aa 5ec0: 849b9d80 40946400 200000c0 200000c0 849b9d80 00000003 dfab5ef4 dfab5ee8 5ee0: 807a77a4 6904e4aa dfab5f14 40946400 00000000 849b9d81 200000c0 849b9d80 5f00: 00000003 83a5b000 dfab5fa4 dfab5f18 805788b8 813c6c68 ecac8b10 83a5b000 5f20: dfab5f3c dfab5f30 81a60ab8 81a60988 dfab5f54 dfab5f40 8025c484 8028d914 5f40: dfab5fb0 40000000 dfab5f84 dfab5f58 802229ec 8025c440 00000000 8281cfb4 5f60: dfab5fb0 0014ca70 ecac8b10 80222940 00000000 6904e4aa dfab5fac 00000000 5f80: 00000000 00316308 00000036 8020029c 83a5b000 00000036 00000000 dfab5fa8 5fa0: 80200060 80578794 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f840bc 5fe0: 76f83ec0 76f83eb0 000195a4 00132510 60000010 00000003 00000000 00000000 Call trace: [<813db538>] (subdev_8255_io) from [<813db270>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:8402bf00 r4:813db538 [<813db218>] (subdev_8255_do_config) from [<813db630>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db218>] (subdev_8255_do_config) from [<813db630>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:8398b000 [<813db5a4>] (subdev_8255_io_init) from [<813db824>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db5a4>] (subdev_8255_io_init) from [<813db824>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:dfab5da4 r5:8402bf00 r4:8398b000 [<813db768>] (dev_8255_attach) from [<813ca720>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:8402bf00 r7:dfab5d90 r6:8402bf44 r5:8402bf00 r4:829d238c [<813ca618>] (comedi_device_attach) from [<813c626c>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83a5b000 r7:200000c0 r6:b5403587 r5:8402bf00 r4:200000c0 [<813c616c>] (do_devconfig_ioctl) from [<813c7238>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83a5b000 r7:200000c0 r6:200000c0 r5:8402bf00 r4:849b9d80 [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6c5c>] (comedi_unlocked_ioctl) from [<805788b8>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83a5b000 r9:00000003 r8:849b9d80 r7:200000c0 r6:849b9d81 r5:00000000 r4:40946400 [<80578788>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfab5fa8 to 0xdfab5ff0) 5fa0: 00000000 00000000 00000003 40946400 200000c0 00000000 5fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f840bc 5fe0: 76f83ec0 76f83eb0 000195a4 00132510 r10:00000036 r9:83a5b000 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