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: 18588 Comm: syz.4.2065 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: 60000113 sp : ebe1dcb8 ip : ebe1dcb8 fp : ebe1dcd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 83d27cc0 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 83d27cc0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 849ef9c0 DAC: fffffffd Register r0 information: slab kmalloc-192 start 83d27cc0 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 83d27cc0 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 0xebe1c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xebe1c000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.4.2065 (pid: 18588, stack limit = 0xebe1c000) Stack: (0xebe1dcb8 to 0xebe1e000) dca0: 813dc200 83d27cc0 dcc0: 00004f27 00004f27 ebe1dcf4 ebe1dcd8 813dbf38 813dc20c 00004f27 8050a85c dce0: 862c0800 862c0800 ebe1dd14 ebe1dcf8 813dc2f8 813dbeec 862c0800 83d27cc0 dd00: ebe1dda4 00004f27 ebe1dd54 ebe1dd18 813dc4ec 813dc278 82af1fe0 86b8ea80 dd20: 828215f0 00000000 00000000 829d240c 83d27cc0 83d27d04 ebe1dd90 83d27cc0 dd40: 00000000 82b25910 ebe1dd8c ebe1dd58 813cb3e8 813dc43c 20000180 00000000 dd60: ebe1dd7c 20000180 83d27cc0 b5403587 20000180 86fcbc00 40946400 00000003 dd80: ebe1de4c ebe1dd90 813c6f34 813cb2ec 35353238 00000000 00000000 00000000 dda0: 00000000 00004f27 00000009 00000002 00000003 00000005 00000cc5 00000007 ddc0: 00000005 0000000a 0000e8ad 00000005 00000001 ffffbffd 00000001 00000000 dde0: 00000000 00000000 0001a44c 000003ff 40000003 00000099 0000caaa 00000006 de00: 20001e57 10000007 00002e6b 00000000 000000d0 00000002 00000001 00000fcc de20: 00000000 3e5a5867 00000000 85592780 83d27cc0 20000180 20000180 86fcbc00 de40: ebe1df14 ebe1de50 813c7f00 813c6e40 00000000 00000000 00000000 3e5a5867 de60: 00000000 00000000 824625b4 0000005f 83ce3de0 83d27cf0 842bd1bc 86fcbc00 de80: ebe1dee4 ebe1de90 807a7ab8 8079e204 00000064 00000001 00000000 ebe1deac dea0: 84fc8550 834eb330 00006400 0000000b ebe1dea0 00000000 00000000 3e5a5867 dec0: 85592780 40946400 20000180 20000180 85592780 00000003 ebe1def4 ebe1dee8 dee0: 807a7bd8 3e5a5867 ebe1df14 40946400 00000000 85592781 20000180 85592780 df00: 00000003 86fcbc00 ebe1dfa4 ebe1df18 80578f40 813c7930 ecac8b10 86fcbc00 df20: ebe1df3c ebe1df30 81a61ce0 81a61bb0 ebe1df54 ebe1df40 8025c484 8028d914 df40: ebe1dfb0 40000000 ebe1df84 ebe1df58 802229ec 8025c440 00000000 8281cfb4 df60: ebe1dfb0 0014cf70 ecac8b10 80222940 00000000 3e5a5867 ebe1dfac 00000000 df80: 00000000 00316308 00000036 8020029c 86fcbc00 00000036 00000000 ebe1dfa8 dfa0: 80200060 80578e1c 00000000 00000000 00000003 40946400 20000180 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f1b0bc dfe0: 76f1aec0 76f1aeb0 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) r7:00004f27 r6:00004f27 r5:83d27cc0 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) r4:862c0800 [<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) r7:00004f27 r6:ebe1dda4 r5:83d27cc0 r4:862c0800 [<813dc430>] (dev_8255_attach) from [<813cb3e8>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:83d27cc0 r7:ebe1dd90 r6:83d27d04 r5:83d27cc0 r4:829d240c [<813cb2e0>] (comedi_device_attach) from [<813c6f34>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:86fcbc00 r7:20000180 r6:b5403587 r5:83d27cc0 r4:20000180 [<813c6e34>] (do_devconfig_ioctl) from [<813c7f00>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:86fcbc00 r7:20000180 r6:20000180 r5:83d27cc0 r4:85592780 [<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) r10:86fcbc00 r9:00000003 r8:85592780 r7:20000180 r6:85592781 r5:00000000 r4:40946400 [<80578e10>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xebe1dfa8 to 0xebe1dff0) dfa0: 00000000 00000000 00000003 40946400 20000180 00000000 dfc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f1b0bc dfe0: 76f1aec0 76f1aeb0 00019294 00132a10 r10:00000036 r9:86fcbc00 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