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BUG: KASAN: slab-use-after-free in __up_read+0x627/0x750 kernel/locking/rwsem.c:1342
Read of size 8 at addr ffff8880208dc868 by task syz-executor.4/6642

CPU: 1 PID: 6642 Comm: syz-executor.4 Not tainted 6.6.0-rc7-syzkaller-00195-g2af9b20dbb39 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xc4/0x620 mm/kasan/report.c:475
 kasan_report+0xda/0x110 mm/kasan/report.c:588
 __up_read+0x627/0x750 kernel/locking/rwsem.c:1342
 iommufd_put_object drivers/iommu/iommufd/iommufd_private.h:149 [inline]
 iommufd_vfio_ioas+0x46c/0x580 drivers/iommu/iommufd/vfio_compat.c:146
 iommufd_fops_ioctl+0x347/0x4d0 drivers/iommu/iommufd/main.c:398
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl fs/ioctl.c:857 [inline]
 __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f904e27cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f904efc20c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f904e39bf80 RCX: 00007f904e27cae9
RDX: 0000000020000080 RSI: 0000000000003b88 RDI: 0000000000000003
RBP: 00007f904e2c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f904e39bf80 R15: 00007ffdd373db28
 </TASK>

Allocated by task 6642:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0xa3/0xb0 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:198 [inline]
 __do_kmalloc_node mm/slab_common.c:1026 [inline]
 __kmalloc+0x60/0x100 mm/slab_common.c:1039
 kmalloc include/linux/slab.h:603 [inline]
 kzalloc include/linux/slab.h:720 [inline]
 _iommufd_object_alloc+0x26/0x1b0 drivers/iommu/iommufd/main.c:40
 iommufd_ioas_alloc drivers/iommu/iommufd/ioas.c:27 [inline]
 iommufd_ioas_alloc_ioctl+0xaf/0x370 drivers/iommu/iommufd/ioas.c:46
 iommufd_fops_ioctl+0x347/0x4d0 drivers/iommu/iommufd/main.c:398
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl fs/ioctl.c:857 [inline]
 __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 6644:
 kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
 kasan_set_track+0x25/0x30 mm/kasan/common.c:52
 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522
 ____kasan_slab_free mm/kasan/common.c:236 [inline]
 ____kasan_slab_free+0x138/0x190 mm/kasan/common.c:200
 kasan_slab_free include/linux/kasan.h:164 [inline]
 __cache_free mm/slab.c:3370 [inline]
 __do_kmem_cache_free mm/slab.c:3557 [inline]
 __kmem_cache_free+0xcc/0x2d0 mm/slab.c:3564
 iommufd_destroy+0x11e/0x180 drivers/iommu/iommufd/main.c:216
 iommufd_fops_ioctl+0x347/0x4d0 drivers/iommu/iommufd/main.c:398
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl fs/ioctl.c:857 [inline]
 __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff8880208dc800
 which belongs to the cache kmalloc-cg-1k of size 1024
The buggy address is located 104 bytes inside of
 freed 1024-byte region [ffff8880208dc800, ffff8880208dcc00)

The buggy address belongs to the physical page:
page:ffffea0000823700 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x208dc
memcg:ffff888028404b41
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0x2()
raw: 00fff00000000800 ffff888012c4d800 ffffea0000836090 ffffea00008d8c90
raw: 0000000000000000 ffff8880208dc000 0000000100000002 ffff888028404b41
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 5066, tgid 5066 (syz-executor.1), ts 323466088331, free_ts 323465997336
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1536
 prep_new_page mm/page_alloc.c:1543 [inline]
 get_page_from_freelist+0xee0/0x2f20 mm/page_alloc.c:3170
 __alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4426
 __alloc_pages_node include/linux/gfp.h:237 [inline]
 kmem_getpages mm/slab.c:1356 [inline]
 cache_grow_begin+0x99/0x3a0 mm/slab.c:2550
 cache_alloc_refill+0x294/0x3a0 mm/slab.c:2923
 ____cache_alloc mm/slab.c:2999 [inline]
 ____cache_alloc mm/slab.c:2982 [inline]
 __do_cache_alloc mm/slab.c:3182 [inline]
 slab_alloc_node mm/slab.c:3230 [inline]
 __kmem_cache_alloc_node+0x3c5/0x470 mm/slab.c:3521
 __do_kmalloc_node mm/slab_common.c:1025 [inline]
 __kmalloc_node+0x52/0x110 mm/slab_common.c:1033
 kmalloc_node include/linux/slab.h:619 [inline]
 kvmalloc_node+0x99/0x1a0 mm/util.c:607
 kvmalloc include/linux/slab.h:737 [inline]
 xt_alloc_table_info+0x3e/0xa0 net/netfilter/x_tables.c:1192
 do_replace net/ipv6/netfilter/ip6_tables.c:1139 [inline]
 do_ip6t_set_ctl+0x534/0xbc0 net/ipv6/netfilter/ip6_tables.c:1636
 nf_setsockopt+0x87/0xe0 net/netfilter/nf_sockopt.c:101
 ipv6_setsockopt+0x12b/0x190 net/ipv6/ipv6_sockglue.c:1017
 tcp_setsockopt+0x9d/0x100 net/ipv4/tcp.c:3673
 __sys_setsockopt+0x2cd/0x5b0 net/socket.c:2325
 __do_sys_setsockopt net/socket.c:2336 [inline]
 __se_sys_setsockopt net/socket.c:2333 [inline]
 __x64_sys_setsockopt+0xbd/0x150 net/socket.c:2333
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1136 [inline]
 free_unref_page_prepare+0x476/0xa40 mm/page_alloc.c:2312
 free_unref_page+0x33/0x3b0 mm/page_alloc.c:2405
 vfree+0x181/0x7a0 mm/vmalloc.c:2842
 copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:882 [inline]
 get_entries net/ipv6/netfilter/ip6_tables.c:1039 [inline]
 do_ip6t_get_ctl+0x8bf/0xab0 net/ipv6/netfilter/ip6_tables.c:1669
 nf_getsockopt+0x76/0xe0 net/netfilter/nf_sockopt.c:116
 ipv6_getsockopt+0x1f9/0x2b0 net/ipv6/ipv6_sockglue.c:1500
 tcp_getsockopt+0x97/0xf0 net/ipv4/tcp.c:4280
 __sys_getsockopt+0x220/0x6a0 net/socket.c:2371
 __do_sys_getsockopt net/socket.c:2386 [inline]
 __se_sys_getsockopt net/socket.c:2383 [inline]
 __x64_sys_getsockopt+0xbd/0x150 net/socket.c:2383
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Memory state around the buggy address:
 ffff8880208dc700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880208dc780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880208dc800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff8880208dc880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880208dc900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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