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: 1 UID: 0 PID: 6558 Comm: syz.1.487 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 : [<813db868>] lr : [<813db854>] psr: 60000013 sp : ea809cb8 ip : ea809cb8 fp : ea809cd4 r10: 00000000 r9 : 00000000 r8 : 00000084 r7 : 00004f27 r6 : 0000009b r5 : 841666c0 r4 : 00004f2a r3 : 0000009b r2 : fee04f2a r1 : 00000001 r0 : 841666c0 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 8581c000 DAC: 00000000 Register r0 information: slab kmalloc-192 start 841666c0 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 841666c0 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 0xea808000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Register r12 information: 2-page vmalloc region starting at 0xea808000 allocated at kernel_clone+0xac/0x3ec kernel/fork.c:2609 Process syz.1.487 (pid: 6558, stack limit = 0xea808000) Stack: (0xea809cb8 to 0xea80a000) 9ca0: 813db808 841666c0 9cc0: 00004f27 00004f27 ea809cf4 ea809cd8 813db540 813db814 00004f27 8050a88c 9ce0: 83396000 83396000 ea809d14 ea809cf8 813db900 813db4f4 83396000 841666c0 9d00: ea809da4 00004f27 ea809d54 ea809d18 813dbaf4 813db880 82af1fe0 832a0a80 9d20: 828215f0 00000000 00000000 829d23cc 841666c0 84166704 ea809d90 841666c0 9d40: 00000000 82b25910 ea809d8c ea809d58 813ca9ec 813dba44 200000c0 00000000 9d60: ea809d7c 200000c0 841666c0 b5403587 200000c0 83ae5400 40946400 00000003 9d80: ea809e4c ea809d90 813c6538 813ca8f0 35353238 00000000 00000000 00000000 9da0: 00000000 00004f27 00000005 00000002 000003fd 00000001 00000cc7 00000fff 9dc0: 5c952399 00010005 000003ff 00000802 00001600 00000001 00000001 00000009 9de0: 0000e1cb 00000009 00000004 08000007 00000395 80000089 fffffffd 00000000 9e00: 00000004 ffffeadb 00000003 0000003c 00000008 00000002 08000000 dffffffa 9e20: 00000000 0e087476 00000000 84e3a000 841666c0 200000c0 200000c0 83ae5400 9e40: ea809f14 ea809e50 813c7504 813c6444 00000000 00000000 00000000 0e087476 9e60: 00000000 00000000 824625b4 0000005f 83d8d7f8 841666f0 84094dd4 83ae5400 9e80: ea809ee4 ea809e90 807a7cbc 8079e0b4 00000064 00000001 00000000 ea809eac 9ea0: 85792850 834dd990 00006400 0000000b ea809ea0 00000000 00000000 0e087476 9ec0: 84e3a000 40946400 200000c0 200000c0 84e3a000 00000006 ea809ef4 ea809ee8 9ee0: 807a7ddc 0e087476 ea809f14 40946400 00000000 84e3a001 200000c0 84e3a000 9f00: 00000006 83ae5400 ea809fa4 ea809f18 80578ee0 813c6f34 ecac8b10 83ae5400 9f20: ea809f3c ea809f30 81a60d80 81a60c50 ea809f54 ea809f40 8025c484 8028d914 9f40: ea809fb0 40000000 ea809f84 ea809f58 802229ec 8025c440 00000000 8281cfb4 9f60: ea809fb0 0014ced0 ecac8b10 80222940 00000000 0e087476 ea809fac 00000000 9f80: 00000000 00316308 00000036 8020029c 83ae5400 00000036 00000000 ea809fa8 9fa0: 80200060 80578dbc 00000000 00000000 00000006 40946400 200000c0 00000000 9fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f700bc 9fe0: 76f6fec0 76f6feb0 0001928c 00132970 60000010 00000006 00000000 00000000 Call trace: [<813db808>] (subdev_8255_io) from [<813db540>] (subdev_8255_do_config+0x58/0x60 drivers/comedi/drivers/comedi_8255.c:115) r7:00004f27 r6:00004f27 r5:841666c0 r4:813db808 [<813db4e8>] (subdev_8255_do_config) from [<813db900>] (__subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]) [<813db4e8>] (subdev_8255_do_config) from [<813db900>] (subdev_8255_io_init+0x8c/0x9c drivers/comedi/drivers/comedi_8255.c:192) r4:83396000 [<813db874>] (subdev_8255_io_init) from [<813dbaf4>] (dev_8255_attach drivers/comedi/drivers/8255.c:83 [inline]) [<813db874>] (subdev_8255_io_init) from [<813dbaf4>] (dev_8255_attach+0xbc/0x114 drivers/comedi/drivers/8255.c:46) r7:00004f27 r6:ea809da4 r5:841666c0 r4:83396000 [<813dba38>] (dev_8255_attach) from [<813ca9ec>] (comedi_device_attach+0x108/0x250 drivers/comedi/drivers.c:1007) r10:82b25910 r9:00000000 r8:841666c0 r7:ea809d90 r6:84166704 r5:841666c0 r4:829d23cc [<813ca8e4>] (comedi_device_attach) from [<813c6538>] (do_devconfig_ioctl+0x100/0x220 drivers/comedi/comedi_fops.c:872) r10:00000003 r9:40946400 r8:83ae5400 r7:200000c0 r6:b5403587 r5:841666c0 r4:200000c0 [<813c6438>] (do_devconfig_ioctl) from [<813c7504>] (comedi_unlocked_ioctl+0x5dc/0x1c50 drivers/comedi/comedi_fops.c:2178) r8:83ae5400 r7:200000c0 r6:200000c0 r5:841666c0 r4:84e3a000 [<813c6f28>] (comedi_unlocked_ioctl) from [<80578ee0>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<813c6f28>] (comedi_unlocked_ioctl) from [<80578ee0>] (do_vfs_ioctl fs/ioctl.c:551 [inline]) [<813c6f28>] (comedi_unlocked_ioctl) from [<80578ee0>] (__do_sys_ioctl fs/ioctl.c:595 [inline]) [<813c6f28>] (comedi_unlocked_ioctl) from [<80578ee0>] (sys_ioctl+0x130/0xba0 fs/ioctl.c:583) r10:83ae5400 r9:00000006 r8:84e3a000 r7:200000c0 r6:84e3a001 r5:00000000 r4:40946400 [<80578db0>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:67) Exception stack(0xea809fa8 to 0xea809ff0) 9fa0: 00000000 00000000 00000006 40946400 200000c0 00000000 9fc0: 00000000 00000000 00316308 00000036 00300000 00000000 00006364 76f700bc 9fe0: 76f6fec0 76f6feb0 0001928c 00132970 r10:00000036 r9:83ae5400 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