8<--- cut here --- Unable to handle kernel paging request at virtual address fee00103 when write [fee00103] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] SMP ARM Modules linked in: CPU: 0 UID: 0 PID: 15866 Comm: syz.0.3909 Not tainted syzkaller #0 PREEMPT Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:99 [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 : [<814a0770>] lr : [<814a075c>] psr: 60000013 sp : dfb65cb8 ip : dfb65cb8 fp : dfb65cd4 r10: 00000100 r9 : 00000004 r8 : dfb65da4 r7 : 00000000 r6 : 0000009b r5 : 843e6e40 r4 : 00000103 r3 : 0000009b r2 : fee00103 r1 : 00000001 r0 : 843e6e40 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 8640b940 DAC: fffffffd Register r0 information: slab kmalloc-192 start 843e6e40 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:1048 Register r3 information: non-paged memory Register r4 information: non-paged memory Register r5 information: slab kmalloc-192 start 843e6e40 pointer offset 0 size 192 Register r6 information: non-paged memory Register r7 information: NULL pointer Register r8 information: 2-page vmalloc region starting at 0xdfb64000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: 2-page vmalloc region starting at 0xdfb64000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Register r12 information: 2-page vmalloc region starting at 0xdfb64000 allocated at kernel_clone+0xc4/0x43c kernel/fork.c:2748 Process syz.0.3909 (pid: 15866, stack limit = 0xdfb64000) Stack: (0xdfb65cb8 to 0xdfb66000) 5ca0: 814a0710 00000100 5cc0: 843e6e40 00000000 dfb65cf4 dfb65cd8 814a044c 814a071c 00000100 80546014 5ce0: 840b7000 840b7000 dfb65d14 dfb65cf8 814a0804 814a0400 843e6e40 00000000 5d00: 840b7000 00000000 dfb65d54 dfb65d18 814a09b4 814a0788 ffffffff 00000004 5d20: 00000000 00000000 843e6e40 82bd965c 843e6e40 00000000 dfb65d90 843e6e40 5d40: 00000000 82d30dfc dfb65d8c dfb65d58 8148f358 814a094c 40946400 00000000 5d60: dfb65d7c 20000600 843e6e40 b5403587 40946400 00000003 00000003 85441880 5d80: dfb65e4c dfb65d90 8148ab5c 8148f25c 35353238 00000000 00000000 00000000 5da0: 00000000 00000100 10000007 00000002 00001000 0000000e 00000005 00000079 5dc0: 00000003 00000800 00000006 ffffffff 00000001 00800008 00400001 00000100 5de0: 00000101 fffffdfb 00000009 0000007f 7fffffff 00000089 0000ca9f fffffffe 5e00: 20001e58 ffffffff 0000f39e 00000003 00000008 0000a6b5 00000000 fffffff8 5e20: 00000000 b6ac00e8 00000000 83832b80 843e6e40 20000600 40946400 00000003 5e40: dfb65f14 dfb65e50 8148be84 8148aa9c 00000000 b6ac00e8 00000000 00000000 5e60: 8254980c dfb65ea4 0000005f 841d9a28 00000064 843e6e70 dfb65ee4 dfb65e88 5e80: 80806188 807fc404 00000064 00000001 00000000 dfb65ea4 8664f210 83434cc0 5ea0: 00006400 0000000b dfb65e98 00000000 00000000 b6ac00e8 00000000 83832b80 5ec0: 40946400 20000600 20000600 83832b80 00000003 85441880 dfb65ef4 dfb65ee8 5ee0: 808062bc b6ac00e8 dfb65f14 00000000 83832b81 40946400 20000600 83832b80 5f00: 00000003 85441880 dfb65fa4 dfb65f18 805bab28 8148bb3c ecac8b10 85441880 5f20: dfb65f3c dfb65f30 81b58280 81b5814c dfb65f54 dfb65f40 8025a7a8 8028e490 5f40: dfb65fb0 40000000 dfb65f84 dfb65f58 80220bdc 8025a764 00000000 82a1eb0c 5f60: dfb65fb0 0013ea70 ecac8b10 80220b30 00000000 b6ac00e8 dfb65fac 00000000 5f80: 00000000 00356310 00000036 8020029c 85441880 00000036 00000000 dfb65fa8 5fa0: 80200060 805ba8f0 00000000 00000000 00000003 40946400 20000600 00000000 5fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f320dc 5fe0: 76f31e88 76f31e78 00018ebc 001308d0 60000010 00000003 00000000 00000000 Call trace: [<814a0710>] (subdev_8255_io) from [<814a044c>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00000000 r6:843e6e40 r5:00000100 r4:814a0710 [<814a03f4>] (subdev_8255_do_config) from [<814a0804>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<814a03f4>] (subdev_8255_do_config) from [<814a0804>] (subdev_8255_io_init+0x88/0x98 drivers/comedi/drivers/comedi_8255.c:192) r4:840b7000 [<814a077c>] (subdev_8255_io_init) from [<814a09b4>] (dev_8255_attach drivers/comedi/drivers/8255.c:84 [inline]) [<814a077c>] (subdev_8255_io_init) from [<814a09b4>] (dev_8255_attach+0x74/0x138 drivers/comedi/drivers/8255.c:46) r7:00000000 r6:840b7000 r5:00000000 r4:843e6e40 [<814a0940>] (dev_8255_attach) from [<8148f358>] (comedi_device_attach+0x108/0x244 drivers/comedi/drivers.c:1101) r10:82d30dfc r9:00000000 r8:843e6e40 r7:dfb65d90 r6:00000000 r5:843e6e40 r4:82bd965c [<8148f250>] (comedi_device_attach) from [<8148ab5c>] (do_devconfig_ioctl+0xcc/0x218 drivers/comedi/comedi_fops.c:930) r10:85441880 r9:00000003 r8:00000003 r7:40946400 r6:b5403587 r5:843e6e40 r4:20000600 [<8148aa90>] (do_devconfig_ioctl) from [<8148be84>] (comedi_unlocked_ioctl+0x354/0x1db8 drivers/comedi/comedi_fops.c:2302) r8:00000003 r7:40946400 r6:20000600 r5:843e6e40 r4:83832b80 [<8148bb30>] (comedi_unlocked_ioctl) from [<805bab28>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<8148bb30>] (comedi_unlocked_ioctl) from [<805bab28>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<8148bb30>] (comedi_unlocked_ioctl) from [<805bab28>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<8148bb30>] (comedi_unlocked_ioctl) from [<805bab28>] (sys_ioctl+0x244/0xb5c fs/ioctl.c:583) r10:85441880 r9:00000003 r8:83832b80 r7:20000600 r6:40946400 r5:83832b81 r4:00000000 [<805ba8e4>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xdfb65fa8 to 0xdfb65ff0) 5fa0: 00000000 00000000 00000003 40946400 20000600 00000000 5fc0: 00000000 00000000 00356310 00000036 003562d8 00000000 00000001 76f320dc 5fe0: 76f31e88 76f31e78 00018ebc 001308d0 r10:00000036 r9:85441880 r8:8020029c r7:00000036 r6:00356310 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