comedi comedi3: c6xdigio: I/O port conflict (0x4f27,3) ================================================================== BUG: KASAN: slab-use-after-free in sysfs_remove_file_ns+0x63/0x70 fs/sysfs/file.c:522 Read of size 8 at addr ffff8880367e9e30 by task syz.2.2739/15328 CPU: 0 UID: 0 PID: 15328 Comm: syz.2.2739 Not tainted 6.16.0-rc7-syzkaller-00127-g302f88ff3584 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 sysfs_remove_file_ns+0x63/0x70 fs/sysfs/file.c:522 sysfs_remove_file include/linux/sysfs.h:777 [inline] driver_remove_file drivers/base/driver.c:201 [inline] driver_remove_file+0x4a/0x60 drivers/base/driver.c:197 remove_bind_files drivers/base/bus.c:605 [inline] bus_remove_driver+0x224/0x2c0 drivers/base/bus.c:743 driver_unregister+0x76/0xb0 drivers/base/driver.c:277 comedi_device_detach+0x13d/0x9e0 drivers/comedi/drivers.c:207 comedi_device_attach+0x43d/0x900 drivers/comedi/drivers.c:1003 do_devconfig_ioctl+0x1a7/0x580 drivers/comedi/comedi_fops.c:855 comedi_unlocked_ioctl+0x165d/0x2f00 drivers/comedi/comedi_fops.c:2156 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff8d718e9a9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff8d803d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ff8d73b5fa0 RCX: 00007ff8d718e9a9 RDX: 00002000000000c0 RSI: 0000000040946400 RDI: 0000000000000003 RBP: 00007ff8d7210d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ff8d73b5fa0 R15: 00007ffff7fe3d58 Allocated by task 12100: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] bus_add_driver+0x92/0x690 drivers/base/bus.c:662 driver_register+0x15c/0x4b0 drivers/base/driver.c:249 c6xdigio_attach drivers/comedi/drivers/c6xdigio.c:253 [inline] c6xdigio_attach+0xa3/0x4b0 drivers/comedi/drivers/c6xdigio.c:238 comedi_device_attach+0x3b3/0x900 drivers/comedi/drivers.c:999 do_devconfig_ioctl+0x1a7/0x580 drivers/comedi/comedi_fops.c:855 comedi_unlocked_ioctl+0x165d/0x2f00 drivers/comedi/comedi_fops.c:2156 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 15329: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x2b4/0x4d0 mm/slub.c:4842 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1e7/0x5a0 lib/kobject.c:737 bus_remove_driver+0x16e/0x2c0 drivers/base/bus.c:749 driver_unregister+0x76/0xb0 drivers/base/driver.c:277 comedi_device_detach+0x13d/0x9e0 drivers/comedi/drivers.c:207 comedi_device_attach+0x43d/0x900 drivers/comedi/drivers.c:1003 do_devconfig_ioctl+0x1a7/0x580 drivers/comedi/comedi_fops.c:855 comedi_unlocked_ioctl+0x165d/0x2f00 drivers/comedi/comedi_fops.c:2156 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880367e9e00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 48 bytes inside of freed 256-byte region [ffff8880367e9e00, ffff8880367e9f00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x367e8 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b842b40 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b842b40 dead000000000100 dead000000000122 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000001 ffffea0000d9fa01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5955, tgid 5955 (udevd), ts 48018947111, free_ts 48004259765 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab mm/slub.c:2619 [inline] new_slab+0x23b/0x330 mm/slub.c:2673 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949 __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x2f2/0x510 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] kmalloc_array_noprof include/linux/slab.h:948 [inline] security_inode_init_security+0x13f/0x390 security/security.c:1829 shmem_mknod+0x22e/0x450 mm/shmem.c:3851 lookup_open.isra.0+0x11d3/0x1580 fs/namei.c:3717 open_last_lookups fs/namei.c:3816 [inline] path_openat+0x893/0x2cb0 fs/namei.c:4052 do_filp_open+0x20b/0x470 fs/namei.c:4082 do_sys_openat2+0x11b/0x1d0 fs/open.c:1437 do_sys_open fs/open.c:1452 [inline] __do_sys_openat fs/open.c:1468 [inline] __se_sys_openat fs/open.c:1463 [inline] __x64_sys_openat+0x174/0x210 fs/open.c:1463 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 page last free pid 5360 tgid 5360 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706 discard_slab mm/slub.c:2717 [inline] __put_partials+0x16d/0x1c0 mm/slub.c:3186 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_lru_noprof+0x1d0/0x3b0 mm/slub.c:4216 alloc_inode+0xc3/0x240 fs/inode.c:348 iget_locked+0x2e4/0x830 fs/inode.c:1439 kernfs_get_inode+0x48/0x460 fs/kernfs/inode.c:251 kernfs_iop_lookup+0x1a7/0x2d0 fs/kernfs/dir.c:1236 __lookup_slow+0x251/0x460 fs/namei.c:1817 lookup_slow fs/namei.c:1834 [inline] walk_component+0x353/0x5b0 fs/namei.c:2138 lookup_last fs/namei.c:2639 [inline] path_lookupat+0x142/0x6d0 fs/namei.c:2663 filename_lookup+0x224/0x5f0 fs/namei.c:2692 do_readlinkat+0xce/0x3a0 fs/stat.c:576 __do_sys_readlink fs/stat.c:613 [inline] __se_sys_readlink fs/stat.c:610 [inline] __x64_sys_readlink+0x78/0xc0 fs/stat.c:610 Memory state around the buggy address: ffff8880367e9d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880367e9d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880367e9e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880367e9e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880367e9f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc 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