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KASAN: slab-use-after-free Read in xfs_buf_rele

Status: auto-obsoleted due to no activity on 2024/09/11 19:16
Subsystems: xfs
[Documentation on labels]
Reported-by: syzbot+f0cdbc7b4728f7f37c98@syzkaller.appspotmail.com
First crash: 596d, last: 565d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in xfs_buf_rele (2) xfs 19 1 396d 386d 0/29 auto-obsoleted due to no activity on 2025/03/09 11:53
upstream KASAN: slab-use-after-free Read in xfs_buf_rele (3) xfs 19 1 246d 242d 0/29 auto-obsoleted due to no activity on 2025/07/27 00:40
upstream KASAN: slab-use-after-free Read in xfs_buf_rele (4) xfs 19 C 31 6h43m 119d 0/29 upstream: reported C repro on 2025/09/02 11:40
linux-4.14 KASAN: use-after-free Read in xfs_buf_rele xfs 19 C 1 1033d 1102d 0/1 upstream: reported C repro on 2022/12/24 01:04
linux-4.19 KASAN: use-after-free Read in xfs_buf_rele 19 syz error 3 1030d 1112d 0/1 upstream: reported syz repro on 2022/12/14 21:15

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in rht_key_hashfn include/linux/rhashtable.h:159 [inline]
BUG: KASAN: slab-use-after-free in rht_head_hashfn include/linux/rhashtable.h:174 [inline]
BUG: KASAN: slab-use-after-free in __rhashtable_remove_fast_one include/linux/rhashtable.h:1007 [inline]
BUG: KASAN: slab-use-after-free in __rhashtable_remove_fast include/linux/rhashtable.h:1093 [inline]
BUG: KASAN: slab-use-after-free in rhashtable_remove_fast include/linux/rhashtable.h:1122 [inline]
BUG: KASAN: slab-use-after-free in xfs_buf_rele_cached fs/xfs/xfs_buf.c:1125 [inline]
BUG: KASAN: slab-use-after-free in xfs_buf_rele+0x1ad1/0x1b40 fs/xfs/xfs_buf.c:1151
Read of size 4 at addr ffff88802bad2408 by task kswapd0/111

CPU: 2 PID: 111 Comm: kswapd0 Not tainted 6.10.0-rc3-syzkaller-00044-g2ccbdf43d5e7 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 rht_key_hashfn include/linux/rhashtable.h:159 [inline]
 rht_head_hashfn include/linux/rhashtable.h:174 [inline]
 __rhashtable_remove_fast_one include/linux/rhashtable.h:1007 [inline]
 __rhashtable_remove_fast include/linux/rhashtable.h:1093 [inline]
 rhashtable_remove_fast include/linux/rhashtable.h:1122 [inline]
 xfs_buf_rele_cached fs/xfs/xfs_buf.c:1125 [inline]
 xfs_buf_rele+0x1ad1/0x1b40 fs/xfs/xfs_buf.c:1151
 xfs_buftarg_shrink_scan+0x1e9/0x2f0 fs/xfs/xfs_buf.c:2003
 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
 shrink_slab+0x18a/0x1310 mm/shrinker.c:662
 shrink_one+0x493/0x7c0 mm/vmscan.c:4790
 shrink_many mm/vmscan.c:4851 [inline]
 lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
 shrink_node mm/vmscan.c:5910 [inline]
 kswapd_shrink_node mm/vmscan.c:6720 [inline]
 balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 9802:
 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:370 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slub.c:4122 [inline]
 __kmalloc_node_noprof+0x215/0x450 mm/slub.c:4129
 kmalloc_node_noprof include/linux/slab.h:681 [inline]
 kvmalloc_node_noprof+0x9d/0x1a0 mm/util.c:634
 bucket_table_alloc.isra.0+0x86/0x470 lib/rhashtable.c:186
 rhashtable_init_noprof+0x43b/0x7d0 lib/rhashtable.c:1071
 xfs_initialize_perag+0x4d8/0xca0 fs/xfs/libxfs/xfs_ag.c:423
 xfs_mountfs+0xdfc/0x1e80 fs/xfs/xfs_mount.c:809
 xfs_fs_fill_super+0x1434/0x1df0 fs/xfs/xfs_super.c:1753
 get_tree_bdev+0x36f/0x610 fs/super.c:1615
 vfs_get_tree+0x8f/0x380 fs/super.c:1780
 do_new_mount fs/namespace.c:3352 [inline]
 path_mount+0x6e1/0x1f10 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount fs/namespace.c:3875 [inline]
 __ia32_sys_mount+0x295/0x320 fs/namespace.c:3875
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Freed by task 9373:
 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:579
 poison_slab_object+0xf7/0x160 mm/kasan/common.c:240
 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2196 [inline]
 slab_free mm/slub.c:4437 [inline]
 kfree+0x12a/0x3b0 mm/slub.c:4558
 kvfree+0x47/0x50 mm/util.c:680
 rhashtable_free_and_destroy+0x16c/0x990 lib/rhashtable.c:1169
 xfs_free_perag+0x11d/0x2c0 fs/xfs/libxfs/xfs_ag.c:267
 xfs_unmountfs+0x15a/0x250 fs/xfs/xfs_mount.c:1128
 xfs_fs_put_super+0x61/0x110 fs/xfs/xfs_super.c:1145
 generic_shutdown_super+0x159/0x3d0 fs/super.c:642
 kill_block_super+0x3b/0x90 fs/super.c:1676
 xfs_kill_sb+0x15/0x50 fs/xfs/xfs_super.c:2045
 deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
 deactivate_super+0xde/0x100 fs/super.c:506
 cleanup_mnt+0x222/0x450 fs/namespace.c:1267
 task_work_run+0x14e/0x250 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218
 __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

The buggy address belongs to the object at ffff88802bad2400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 8 bytes inside of
 freed 512-byte region [ffff88802bad2400, ffff88802bad2600)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2bad0
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffefff(slab)
raw: 00fff00000000040 ffff888015442c80 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000100010 00000001ffffefff 0000000000000000
head: 00fff00000000040 ffff888015442c80 0000000000000000 dead000000000001
head: 0000000000000000 0000000000100010 00000001ffffefff 0000000000000000
head: 00fff00000000002 ffffea0000aeb401 ffffffffffffffff 0000000000000000
head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6076, tgid 6076 (syz-executor.3), ts 149892687950, free_ts 147164271877
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1468
 prep_new_page mm/page_alloc.c:1476 [inline]
 get_page_from_freelist+0x136a/0x2e50 mm/page_alloc.c:3420
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4678
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x56/0x110 mm/slub.c:2265
 allocate_slab mm/slub.c:2428 [inline]
 new_slab+0x84/0x260 mm/slub.c:2481
 ___slab_alloc+0xdac/0x1870 mm/slub.c:3667
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3757
 __slab_alloc_node mm/slub.c:3810 [inline]
 slab_alloc_node mm/slub.c:3989 [inline]
 __do_kmalloc_node mm/slub.c:4121 [inline]
 __kmalloc_noprof+0x37f/0x420 mm/slub.c:4135
 kmalloc_noprof include/linux/slab.h:664 [inline]
 kzalloc_noprof include/linux/slab.h:778 [inline]
 fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x337/0x1ae0 net/ipv6/route.c:3761
 addrconf_f6i_alloc+0x393/0x670 net/ipv6/route.c:4588
 ipv6_add_addr+0x538/0x2090 net/ipv6/addrconf.c:1120
 inet6_addr_add+0x3bb/0xbe0 net/ipv6/addrconf.c:3059
 inet6_rtm_newaddr+0x11ea/0x1ac0 net/ipv6/addrconf.c:5047
 rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6635
 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2564
page last free pid 45 tgid 45 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1088 [inline]
 free_unref_page+0x64a/0xe40 mm/page_alloc.c:2583
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3941 [inline]
 slab_alloc_node mm/slub.c:4001 [inline]
 kmalloc_trace_noprof+0x11e/0x310 mm/slub.c:4148
 kmalloc_noprof include/linux/slab.h:660 [inline]
 netdevice_queue_work drivers/infiniband/core/roce_gid_mgmt.c:642 [inline]
 netdevice_event+0x368/0xa10 drivers/infiniband/core/roce_gid_mgmt.c:801
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1992
 call_netdevice_notifiers_extack net/core/dev.c:2030 [inline]
 call_netdevice_notifiers net/core/dev.c:2044 [inline]
 unregister_netdevice_many_notify+0x8a1/0x19f0 net/core/dev.c:11219
 unregister_netdevice_many net/core/dev.c:11277 [inline]
 default_device_exit_batch+0x731/0x9b0 net/core/dev.c:11760
 ops_exit_list+0x128/0x180 net/core/net_namespace.c:178
 cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640
 process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147

Memory state around the buggy address:
 ffff88802bad2300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802bad2380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802bad2400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88802bad2480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802bad2500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/13 19:15 upstream 2ccbdf43d5e7 c2e07261 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 KASAN: slab-use-after-free Read in xfs_buf_rele
2024/05/13 15:11 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fda5695d692c 9026e142 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 KASAN: slab-use-after-free Read in xfs_buf_rele
* Struck through repros no longer work on HEAD.