On Sun, 22 Sept 2024 at 21:30, 'Chuck Lever III' via syzkaller-bugs <syzkaller-bugs@xxxxxxxxxxxxxxxx> wrote: > > > > > On Sep 20, 2024, at 3:13 PM, Jeff Layton <jlayton@xxxxxxxxxx> wrote: > > > > On Fri, 2024-09-20 at 18:51 +0000, Chuck Lever III wrote: > >> > >>> On Sep 19, 2024, at 10:57 PM, NeilBrown <neilb@xxxxxxx> wrote: > >>> > >>> On Thu, 19 Sep 2024, Jeff Layton wrote: > >>>> On Wed, 2024-09-18 at 08:38 -0700, syzbot wrote: > >>>>> Hello, > >>>>> > >>>>> syzbot found the following issue on: > >>>>> > >>>>> HEAD commit: a430d95c5efa Merge tag 'lsm-pr-20240911' of git://git.kern.. > >>>>> git tree: upstream > >>>>> console output: https://syzkaller.appspot.com/x/log.txt?x=17c7469f980000 > >>>>> kernel config: https://syzkaller.appspot.com/x/.config?x=a69c66e868285a9d > >>>>> dashboard link: https://syzkaller.appspot.com/bug?extid=24cd636199753ac5e0ca > >>>>> compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 > >>>>> > >>>>> Unfortunately, I don't have any reproducer for this issue yet. > >>>>> > >>>>> Downloadable assets: > >>>>> disk image: https://storage.googleapis.com/syzbot-assets/7f3aff905e91/disk-a430d95c.raw.xz > >>>>> vmlinux: https://storage.googleapis.com/syzbot-assets/a468ce8431f0/vmlinux-a430d95c.xz > >>>>> kernel image: https://storage.googleapis.com/syzbot-assets/80d4f1150155/bzImage-a430d95c.xz > >>>>> > >>>>> IMPORTANT: if you fix the issue, please add the following tag to the commit: > >>>>> Reported-by: syzbot+24cd636199753ac5e0ca@xxxxxxxxxxxxxxxxxxxxxxxxx > >>>>> > >>>>> svc: failed to register nfsdv3 RPC service (errno 111). > >>>>> svc: failed to register nfsaclv3 RPC service (errno 111). > >>>>> ================================================================== > >>>>> BUG: KASAN: slab-use-after-free in list_add include/linux/list.h:169 [inline] > >>>>> BUG: KASAN: slab-use-after-free in rhashtable_walk_enter+0x333/0x370 lib/rhashtable.c:684 > >>>>> Read of size 8 at addr ffff8880773fa010 by task syz.2.11924/9970 > >>>>> > >>>>> CPU: 0 UID: 0 PID: 9970 Comm: syz.2.11924 Not tainted 6.11.0-syzkaller-02574-ga430d95c5efa #0 > >>>>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 > >>>>> Call Trace: > >>>>> <TASK> > >>>>> __dump_stack lib/dump_stack.c:93 [inline] > >>>>> dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 > >>>>> 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 > >>>>> list_add include/linux/list.h:169 [inline] > >>>>> rhashtable_walk_enter+0x333/0x370 lib/rhashtable.c:684 > >>>>> rhltable_walk_enter include/linux/rhashtable.h:1262 [inline] > >>>>> __nfsd_file_cache_purge+0xad/0x490 fs/nfsd/filecache.c:805 > >>>>> nfsd_file_cache_shutdown+0xcf/0x480 fs/nfsd/filecache.c:897 > >>>>> nfsd_shutdown_generic fs/nfsd/nfssvc.c:329 [inline] > >>>>> nfsd_shutdown_generic fs/nfsd/nfssvc.c:323 [inline] > >>>>> nfsd_startup_net fs/nfsd/nfssvc.c:444 [inline] > >>>>> nfsd_svc+0x6d4/0x970 fs/nfsd/nfssvc.c:817 > >>>>> nfsd_nl_threads_set_doit+0x52c/0xbc0 fs/nfsd/nfsctl.c:1714 > >>>>> genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115 > >>>>> genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] > >>>>> genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210 > >>>>> netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2550 > >>>>> genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 > >>>>> netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline] > >>>>> netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357 > >>>>> netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901 > >>>>> sock_sendmsg_nosec net/socket.c:730 [inline] > >>>>> __sock_sendmsg net/socket.c:745 [inline] > >>>>> ____sys_sendmsg+0x9ae/0xb40 net/socket.c:2603 > >>>>> ___sys_sendmsg+0x135/0x1e0 net/socket.c:2657 > >>>>> __sys_sendmsg+0x117/0x1f0 net/socket.c:2686 > >>>>> do_syscall_x64 arch/x86/entry/common.c:52 [inline] > >>>>> do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 > >>>>> entry_SYSCALL_64_after_hwframe+0x77/0x7f > >>>>> RIP: 0033:0x7fd947f7def9 > >>>>> 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:00007fd948e38038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e > >>>>> RAX: ffffffffffffffda RBX: 00007fd948135f80 RCX: 00007fd947f7def9 > >>>>> RDX: 0000000000000004 RSI: 0000000020000280 RDI: 0000000000000003 > >>>>> RBP: 00007fd947ff0b76 R08: 0000000000000000 R09: 0000000000000000 > >>>>> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > >>>>> R13: 0000000000000000 R14: 00007fd948135f80 R15: 00007ffc6cab9d78 > >>>>> </TASK> > >>>>> > >>>>> Allocated by task 8716: > >>>>> 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:4159 [inline] > >>>>> __kmalloc_node_track_caller_noprof+0x20f/0x440 mm/slub.c:4178 > >>>>> kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609 > >>>>> __alloc_skb+0x164/0x380 net/core/skbuff.c:678 > >>>>> alloc_skb include/linux/skbuff.h:1322 [inline] > >>>>> nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] > >>>>> nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] > >>>>> nsim_dev_trap_report_work+0x2a4/0xc80 drivers/net/netdevsim/dev.c:850 > >>>>> process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231 > >>>>> process_scheduled_works kernel/workqueue.c:3312 [inline] > >>>>> worker_thread+0x6c8/0xf00 kernel/workqueue.c:3393 > >>>>> 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 > >>>>> > >>>>> Freed by task 8716: > >>>>> 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:2250 [inline] > >>>>> slab_free mm/slub.c:4474 [inline] > >>>>> kfree+0x12a/0x3b0 mm/slub.c:4595 > >>>>> skb_kfree_head net/core/skbuff.c:1086 [inline] > >>>>> skb_free_head+0x108/0x1d0 net/core/skbuff.c:1098 > >>>>> skb_release_data+0x75d/0x990 net/core/skbuff.c:1125 > >>>>> skb_release_all net/core/skbuff.c:1190 [inline] > >>>>> __kfree_skb net/core/skbuff.c:1204 [inline] > >>>>> consume_skb net/core/skbuff.c:1436 [inline] > >>>>> consume_skb+0xbf/0x100 net/core/skbuff.c:1430 > >>>>> nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline] > >>>>> nsim_dev_trap_report_work+0x878/0xc80 drivers/net/netdevsim/dev.c:850 > >>>>> process_one_work+0x958/0x1ad0 kernel/workqueue.c:3231 > >>>>> process_scheduled_works kernel/workqueue.c:3312 [inline] > >>>>> worker_thread+0x6c8/0xf00 kernel/workqueue.c:3393 > >>>>> 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 > >>>>> > >>>>> The buggy address belongs to the object at ffff8880773fa000 > >>>>> which belongs to the cache kmalloc-4k of size 4096 > >>>>> The buggy address is located 16 bytes inside of > >>>>> freed 4096-byte region [ffff8880773fa000, ffff8880773fb000) > >>>>> > >>>>> The buggy address belongs to the physical page: > >>>>> page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x773f8 > >>>>> head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 > >>>>> flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) > >>>>> page_type: 0xfdffffff(slab) > >>>>> raw: 00fff00000000040 ffff88801ac42140 ffffea0001e63600 dead000000000002 > >>>>> raw: 0000000000000000 0000000000040004 00000001fdffffff 0000000000000000 > >>>>> head: 00fff00000000040 ffff88801ac42140 ffffea0001e63600 dead000000000002 > >>>>> head: 0000000000000000 0000000000040004 00000001fdffffff 0000000000000000 > >>>>> head: 00fff00000000003 ffffea0001dcfe01 ffffffffffffffff 0000000000000000 > >>>>> head: 0000000700000008 0000000000000000 00000000ffffffff 0000000000000000 > >>>>> page dumped because: kasan: bad access detected > >>>>> page_owner tracks the page as allocated > >>>>> page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5240, tgid 5240 (syz-executor), ts 74499202771, free_ts 74134964798 > >>>>> set_page_owner include/linux/page_owner.h:32 [inline] > >>>>> post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1500 > >>>>> prep_new_page mm/page_alloc.c:1508 [inline] > >>>>> get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3446 > >>>>> __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4702 > >>>>> __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] > >>>>> alloc_pages_node_noprof include/linux/gfp.h:296 [inline] > >>>>> alloc_slab_page+0x4e/0xf0 mm/slub.c:2319 > >>>>> allocate_slab mm/slub.c:2482 [inline] > >>>>> new_slab+0x84/0x260 mm/slub.c:2535 > >>>>> ___slab_alloc+0xdac/0x1870 mm/slub.c:3721 > >>>>> __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3811 > >>>>> __slab_alloc_node mm/slub.c:3864 [inline] > >>>>> slab_alloc_node mm/slub.c:4026 [inline] > >>>>> __do_kmalloc_node mm/slub.c:4158 [inline] > >>>>> __kmalloc_noprof+0x379/0x410 mm/slub.c:4171 > >>>>> kmalloc_noprof include/linux/slab.h:694 [inline] > >>>>> tomoyo_realpath_from_path+0xbf/0x710 security/tomoyo/realpath.c:251 > >>>>> tomoyo_get_realpath security/tomoyo/file.c:151 [inline] > >>>>> tomoyo_path_number_perm+0x245/0x5b0 security/tomoyo/file.c:723 > >>>>> security_file_ioctl+0x9b/0x240 security/security.c:2908 > >>>>> __do_sys_ioctl fs/ioctl.c:901 [inline] > >>>>> __se_sys_ioctl fs/ioctl.c:893 [inline] > >>>>> __x64_sys_ioctl+0xbb/0x210 fs/ioctl.c:893 > >>>>> do_syscall_x64 arch/x86/entry/common.c:52 [inline] > >>>>> do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 > >>>>> entry_SYSCALL_64_after_hwframe+0x77/0x7f > >>>>> page last free pid 5233 tgid 5233 stack trace: > >>>>> reset_page_owner include/linux/page_owner.h:25 [inline] > >>>>> free_pages_prepare mm/page_alloc.c:1101 [inline] > >>>>> free_unref_folios+0x9e9/0x1390 mm/page_alloc.c:2667 > >>>>> folios_put_refs+0x560/0x760 mm/swap.c:1039 > >>>>> free_pages_and_swap_cache+0x36d/0x510 mm/swap_state.c:332 > >>>>> __tlb_batch_free_encoded_pages+0xf9/0x290 mm/mmu_gather.c:136 > >>>>> tlb_batch_pages_flush mm/mmu_gather.c:149 [inline] > >>>>> tlb_flush_mmu_free mm/mmu_gather.c:366 [inline] > >>>>> tlb_flush_mmu mm/mmu_gather.c:373 [inline] > >>>>> tlb_finish_mmu+0x168/0x7b0 mm/mmu_gather.c:465 > >>>>> unmap_region+0x342/0x420 mm/mmap.c:2441 > >>>>> do_vmi_align_munmap+0x1107/0x19c0 mm/mmap.c:2754 > >>>>> do_vmi_munmap+0x231/0x410 mm/mmap.c:2830 > >>>>> __vm_munmap+0x142/0x330 mm/mmap.c:3109 > >>>>> __do_sys_munmap mm/mmap.c:3126 [inline] > >>>>> __se_sys_munmap mm/mmap.c:3123 [inline] > >>>>> __x64_sys_munmap+0x61/0x90 mm/mmap.c:3123 > >>>>> do_syscall_x64 arch/x86/entry/common.c:52 [inline] > >>>>> do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 > >>>>> entry_SYSCALL_64_after_hwframe+0x77/0x7f > >>>>> > >>>>> Memory state around the buggy address: > >>>>> ffff8880773f9f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > >>>>> ffff8880773f9f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > >>>>>> ffff8880773fa000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > >>>>> ^ > >>>>> ffff8880773fa080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > >>>>> ffff8880773fa100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > >>>>> ================================================================== > >>>>> > >>>>> > >>>>> --- > >>>>> This report is generated by a bot. It may contain errors. > >>>>> See https://goo.gl/tpsmEJ for more information about syzbot. > >>>>> syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > >>>>> > >>>>> syzbot will keep track of this issue. See: > >>>>> https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > >>>>> > >>>>> If the report is already addressed, let syzbot know by replying with: > >>>>> #syz fix: exact-commit-title > >>>>> > >>>>> If you want to overwrite report's subsystems, reply with: > >>>>> #syz set subsystems: new-subsystem > >>>>> (See the list of subsystem names on the web dashboard) > >>>>> > >>>>> If the report is a duplicate of another one, reply with: > >>>>> #syz dup: exact-subject-of-another-report > >>>>> > >>>>> If you want to undo deduplication, reply with: > >>>>> #syz undup > >>>> > >>>> So we're tearing down the server and cleaning out the nfsd_file hash, > >>>> and we hit a UAF. That probably means that we freed a nfsd_file without > >>>> removing it from the hash? Maybe we should add a WARN_ON() in > >>>> nfsd_file_slab_free that checks whether the item is still hashed? > >>>> > >>>> It is strange though. struct nfsd_file is 112 bytes on my machine, but > >>>> the warning is about a 4k allocation. I guess that just means that the > >>>> page got recycled into a different slabcache. > >>> > >>> The code that is crashing hasn't come close to touching anything that is > >>> thought to be an nfsd_file. > >>> The error is detected in the list_add() in rhashtable_walk_enter() when > >>> the new on-stack iterator is being attached to the bucket_table that is being > >>> iterated. So that bucket_table must (now) be an invalid address. > >>> > >>> The handling of NFSD_FILE_CACHE_UP is strange. nfsd_file_cache_init() > >>> sets it, but doesn't clear it on failure. So if nfsd_file_cache_init() > >>> fails for some reason, nfsd_file_cache_shutdown() would still try to > >>> clean up if it was called. > >>> > >>> So suppose nfsd_startup_generic() is called. It increments nfsd_users > >>> from 0 so continues to nfsd_file_cache_init() which fails for some > >>> reason after initialising nfsd_file_rhltable and then destroying it. > >>> This will leave nfsd_file_rhltable.tbl as a pointer to a large > >>> allocation which has been freed. nfsd_startup_generic() will then > >>> decrement nfsd_users back to zero, but NFSD_FILE_CACHE_UP will still be > >>> set. > >>> > >>> When nfsd_startup_generic() is called again, nfsd_file_cache_init() will > >>> skip initialisation because NFSD_FILE_CACHE_UP is set. When > >>> nfsd_file_cache_shutdown() is then called it will clean up an rhltable > >>> that has already been destroyed. We get exactly the reported symptom. > >>> > >>> I *think* nfsd_file_cache_init() can only fail with -ENOMEM and I would > >>> expect to see a warning when that happened. In any case > >>> nfsd_file_cache_init() uses pr_err() for any failure except > >>> rhltable_init(), and that only fails if the params are inconsistent. > >>> > >>> So I think there are problems with NFSD_FILE_CACHE_UP settings and I > >>> think they could trigger this bug if a kmalloc failed, but I don't think > >>> that a kmalloc failed and I think there must be some other explanation > >>> here. > >> > >> Also, the FILE_CACHE_UP logic has been around for several releases. > >> Why is this UAF showing up only now? The "unable to register" > >> messages suggest a possible reason. > >> > > > > Good point. I didn't notice those. 111 is ECONNREFUSED, so it sounds > > like rpcbind isn't up in this situation. Maybe that's a hint toward a > > reproducer? > > I've enabled KASAN, shut down NFSD, and disabled rpcbind. > Using the /proc/fs/nfsd/threads interface, I can reproduce > the "unable to register" messages, but not the KASAN splat. > > I think Neil's analysis above is correct or very close. I > don't have nfsdctl set up here, but my guess is that the > syzbot is abusing the new netlink command API, causing > nfsd_file_cache_init() to fail somehow and the error > flow is leaving the kernel vulnerable to a UAF. Based on the fact that it happened 8 times and no reproducer so far: 1. Likely to be a true bug in nsfd 2. LIkely to be a hard to trigger race condition 3. The fact that alloc/free frequently don't match access tack suggests that the access happens long after the free (pointer left in some global structure) I also found one with matching stacks here: https://syzkaller.appspot.com/text?tag=CrashLog&x=128bd39f980000 It looks like the object is freed during creation: [ 3239.085992][ T8199] __kmem_cache_create_args(nfsd_file) failed with error -22 [ 3239.117916][ T8199] CPU: 1 UID: 0 PID: 8199 Comm: syz.1.6492 Not tainted 6.12.0-rc1-syzkaller-00031-ge32cde8d2bd7 #0 [ 3239.129138][ T8199] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 [ 3239.139255][ T8199] Call Trace: [ 3239.142756][ T8199] <TASK> [ 3239.145753][ T8199] dump_stack_lvl+0x16c/0x1f0 [ 3239.150510][ T8199] __kmem_cache_create_args+0x130/0x3c0 [ 3239.156126][ T8199] nfsd_file_cache_init+0x126/0x4d0 [ 3239.161408][ T8199] ? net_generic+0xf4/0x2a0 [ 3239.165992][ T8199] nfsd_svc+0x5db/0x940 [ 3239.170309][ T8199] nfsd_nl_threads_set_doit+0x535/0xbe0 [ 3239.175933][ T8199] genl_family_rcv_msg_doit+0x202/0x2f0 [ 3239.181560][ T8199] ? __pfx_genl_family_rcv_msg_doit+0x10/0x10 [ 3239.187720][ T8199] ? bpf_lsm_capable+0x9/0x10 [ 3239.192470][ T8199] ? security_capable+0x7e/0x260 [ 3239.197482][ T8199] genl_rcv_msg+0x565/0x800 [ 3239.202063][ T8199] ? __pfx_genl_rcv_msg+0x10/0x10 [ 3239.207201][ T8199] ? __pfx_nfsd_nl_threads_set_doit+0x10/0x10 [ 3239.213336][ T8199] netlink_rcv_skb+0x165/0x410 [ 3239.218144][ T8199] ? __pfx_genl_rcv_msg+0x10/0x10 [ 3239.223301][ T8199] ? __pfx_netlink_rcv_skb+0x10/0x10 [ 3239.228636][ T8199] ? down_read+0xc9/0x330 [ 3239.233012][ T8199] ? __pfx_down_read+0x10/0x10 [ 3239.237833][ T8199] ? netlink_deliver_tap+0x1ae/0xcf0 [ 3239.243429][ T8199] genl_rcv+0x28/0x40 [ 3239.247447][ T8199] netlink_unicast+0x53c/0x7f0 [ 3239.252257][ T8199] ? __pfx_netlink_unicast+0x10/0x10 [ 3239.257579][ T8199] ? __phys_addr_symbol+0x30/0x80 [ 3239.262641][ T8199] ? __check_object_size+0x488/0x710 [ 3239.267972][ T8199] netlink_sendmsg+0x8b8/0xd70 [ 3239.272776][ T8199] ? __pfx_netlink_sendmsg+0x10/0x10 [ 3239.278115][ T8199] ____sys_sendmsg+0x9ae/0xb40 [ 3239.282921][ T8199] ? copy_msghdr_from_user+0x10b/0x160 [ 3239.288434][ T8199] ? __pfx_____sys_sendmsg+0x10/0x10 [ 3239.293765][ T8199] ? netlink_recvmsg+0x81c/0xf30 [ 3239.298736][ T8199] ? __pfx___lock_acquire+0x10/0x10 [ 3239.303989][ T8199] ___sys_sendmsg+0x135/0x1e0 [ 3239.308715][ T8199] ? __pfx____sys_sendmsg+0x10/0x10 [ 3239.313976][ T8199] ? lock_acquire+0x2f/0xb0 [ 3239.318521][ T8199] ? __fget_files+0x40/0x3f0 [ 3239.323155][ T8199] ? fdget+0x176/0x210 [ 3239.327348][ T8199] __sys_sendmsg+0x117/0x1f0 [ 3239.331985][ T8199] ? __pfx___sys_sendmsg+0x10/0x10 [ 3239.337153][ T8199] ? __x64_sys_futex+0x1e1/0x4c0 [ 3239.342236][ T8199] do_syscall_64+0xcd/0x250 [ 3239.346787][ T8199] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 3239.352716][ T8199] RIP: 0033:0x7fd3c577dff9 [ 3239.357157][ T8199] 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 [ 3239.376798][ T8199] RSP: 002b:00007fd3c65a7038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 3239.385282][ T8199] RAX: ffffffffffffffda RBX: 00007fd3c5935f80 RCX: 00007fd3c577dff9 [ 3239.393282][ T8199] RDX: 0000000000008004 RSI: 0000000020000140 RDI: 0000000000000006 [ 3239.401287][ T8199] RBP: 00007fd3c57f0296 R08: 0000000000000000 R09: 0000000000000000 [ 3239.409291][ T8199] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 3239.417296][ T8199] R13: 0000000000000000 R14: 00007fd3c5935f80 R15: 00007ffca7d46f08 [ 3239.425314][ T8199] </TASK> [ 3239.605040][ T8199] nfsd: unable to create nfsd_file_slab [ 3242.331528][ T8252] netlink: zone id is out of range [ 3242.353608][ T8252] netlink: zone id is out of range [ 3242.375964][ T8252] netlink: zone id is out of range [ 3242.381340][ T8252] netlink: zone id is out of range [ 3242.432868][ T8252] netlink: zone id is out of range [ 3242.506182][ T8252] netlink: zone id is out of range [ 3242.529087][ T8252] netlink: zone id is out of range [ 3242.574253][ T8252] netlink: zone id is out of range [ 3245.016756][ T8292] sock: sock_set_timeout: `syz.3.6511' (pid 8292) tries to set negative timeout [ 3245.419913][ T8295] svc: failed to register nfsdv3 RPC service (errno 111). [ 3245.467727][ T8295] svc: failed to register nfsaclv3 RPC service (errno 111). [ 3245.693668][ T8295] ================================================================== [ 3245.701818][ T8295] BUG: KASAN: slab-use-after-free in rhashtable_walk_enter+0x333/0x370 [ 3245.710150][ T8295] Read of size 8 at addr ffff8880301ac010 by task syz.1.6512/8295 [ 3245.718011][ T8295] [ 3245.720376][ T8295] CPU: 1 UID: 0 PID: 8295 Comm: syz.1.6512 Not tainted 6.12.0-rc1-syzkaller-00031-ge32cde8d2bd7 #0 [ 3245.731118][ T8295] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 [ 3245.741404][ T8295] Call Trace: [ 3245.744728][ T8295] <TASK> [ 3245.747702][ T8295] dump_stack_lvl+0x116/0x1f0 [ 3245.752629][ T8295] print_report+0xc3/0x620 [ 3245.757152][ T8295] ? __virt_addr_valid+0x5e/0x590 [ 3245.762261][ T8295] ? __phys_addr+0xc6/0x150 [ 3245.766862][ T8295] kasan_report+0xd9/0x110 [ 3245.771374][ T8295] ? rhashtable_walk_enter+0x333/0x370 [ 3245.776919][ T8295] ? rhashtable_walk_enter+0x333/0x370 [ 3245.782467][ T8295] rhashtable_walk_enter+0x333/0x370 [ 3245.787843][ T8295] __nfsd_file_cache_purge+0xad/0x470 [ 3245.793299][ T8295] ? __pfx___nfsd_file_cache_purge+0x10/0x10 [ 3245.799445][ T8295] ? lockdep_hardirqs_on+0x7c/0x110 [ 3245.804721][ T8295] ? enable_work+0x246/0x340 [ 3245.809637][ T8295] ? __pfx_enable_work+0x10/0x10 [ 3245.814651][ T8295] nfsd_file_cache_shutdown+0xcf/0x4e0 [ 3245.820203][ T8295] nfsd_svc+0x6a9/0x940 [ 3245.824435][ T8295] nfsd_nl_threads_set_doit+0x535/0xbe0 [ 3245.830066][ T8295] genl_family_rcv_msg_doit+0x202/0x2f0 [ 3245.835692][ T8295] ? __pfx_genl_family_rcv_msg_doit+0x10/0x10 [ 3245.841845][ T8295] ? bpf_lsm_capable+0x9/0x10 [ 3245.846733][ T8295] ? security_capable+0x7e/0x260 [ 3245.851836][ T8295] genl_rcv_msg+0x565/0x800 [ 3245.856427][ T8295] ? __pfx_genl_rcv_msg+0x10/0x10 [ 3245.861530][ T8295] ? __pfx_nfsd_nl_threads_set_doit+0x10/0x10 [ 3245.867684][ T8295] netlink_rcv_skb+0x165/0x410 [ 3245.872559][ T8295] ? __pfx_genl_rcv_msg+0x10/0x10 [ 3245.877679][ T8295] ? __pfx_netlink_rcv_skb+0x10/0x10 [ 3245.883041][ T8295] ? down_read+0xc9/0x330 [ 3245.887446][ T8295] ? __pfx_down_read+0x10/0x10 [ 3245.892295][ T8295] ? netlink_deliver_tap+0x1ae/0xcf0 [ 3245.897649][ T8295] genl_rcv+0x28/0x40 [ 3245.901698][ T8295] netlink_unicast+0x53c/0x7f0 [ 3245.906584][ T8295] ? __pfx_netlink_unicast+0x10/0x10 [ 3245.912041][ T8295] ? __phys_addr_symbol+0x30/0x80 [ 3245.917161][ T8295] ? __check_object_size+0x488/0x710 [ 3245.922542][ T8295] netlink_sendmsg+0x8b8/0xd70 [ 3245.927393][ T8295] ? __pfx_netlink_sendmsg+0x10/0x10 [ 3245.932758][ T8295] ____sys_sendmsg+0x9ae/0xb40 [ 3245.937616][ T8295] ? copy_msghdr_from_user+0x10b/0x160 [ 3245.943164][ T8295] ? __pfx_____sys_sendmsg+0x10/0x10 [ 3245.948531][ T8295] ? netlink_recvmsg+0x81c/0xf30 [ 3245.953535][ T8295] ? __pfx___lock_acquire+0x10/0x10 [ 3245.958906][ T8295] ___sys_sendmsg+0x135/0x1e0 [ 3245.963667][ T8295] ? __pfx____sys_sendmsg+0x10/0x10 [ 3245.968960][ T8295] ? lock_acquire+0x2f/0xb0 [ 3245.973562][ T8295] ? __fget_files+0x40/0x3f0 [ 3245.978240][ T8295] ? fdget+0x176/0x210 [ 3245.982379][ T8295] __sys_sendmsg+0x117/0x1f0 [ 3245.987050][ T8295] ? __pfx___sys_sendmsg+0x10/0x10 [ 3245.992252][ T8295] ? __x64_sys_futex+0x1e1/0x4c0 [ 3245.997285][ T8295] do_syscall_64+0xcd/0x250 [ 3246.001884][ T8295] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 3246.007856][ T8295] RIP: 0033:0x7fd3c577dff9 [ 3246.012333][ T8295] 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 [ 3246.032094][ T8295] RSP: 002b:00007fd3c65a7038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 3246.040597][ T8295] RAX: ffffffffffffffda RBX: 00007fd3c5935f80 RCX: 00007fd3c577dff9 [ 3246.048626][ T8295] RDX: 0000000000008004 RSI: 0000000020000140 RDI: 0000000000000003 [ 3246.056739][ T8295] RBP: 00007fd3c57f0296 R08: 0000000000000000 R09: 0000000000000000 [ 3246.064770][ T8295] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 3246.072801][ T8295] R13: 0000000000000000 R14: 00007fd3c5935f80 R15: 00007ffca7d46f08 [ 3246.080840][ T8295] </TASK> [ 3246.083901][ T8295] [ 3246.086354][ T8295] Allocated by task 8199: [ 3246.090716][ T8295] kasan_save_stack+0x33/0x60 [ 3246.095449][ T8295] kasan_save_track+0x14/0x30 [ 3246.100192][ T8295] __kasan_kmalloc+0xaa/0xb0 [ 3246.104861][ T8295] __kmalloc_node_noprof+0x211/0x440 [ 3246.110263][ T8295] __kvmalloc_node_noprof+0xad/0x1a0 [ 3246.115630][ T8295] bucket_table_alloc.isra.0+0x86/0x460 [ 3246.121336][ T8295] rhashtable_init_noprof+0x43b/0x7d0 [ 3246.126797][ T8295] rhltable_init_noprof+0x20/0x60 [ 3246.131899][ T8295] nfsd_file_cache_init+0xd2/0x4d0 [ 3246.137089][ T8295] nfsd_svc+0x5db/0x940 [ 3246.141306][ T8295] nfsd_nl_threads_set_doit+0x535/0xbe0 [ 3246.147008][ T8295] genl_family_rcv_msg_doit+0x202/0x2f0 [ 3246.152628][ T8295] genl_rcv_msg+0x565/0x800 [ 3246.157209][ T8295] netlink_rcv_skb+0x165/0x410 [ 3246.162039][ T8295] genl_rcv+0x28/0x40 [ 3246.166089][ T8295] netlink_unicast+0x53c/0x7f0 [ 3246.170946][ T8295] netlink_sendmsg+0x8b8/0xd70 [ 3246.175774][ T8295] ____sys_sendmsg+0x9ae/0xb40 [ 3246.180605][ T8295] ___sys_sendmsg+0x135/0x1e0 [ 3246.185447][ T8295] __sys_sendmsg+0x117/0x1f0 [ 3246.190110][ T8295] do_syscall_64+0xcd/0x250 [ 3246.194685][ T8295] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 3246.200643][ T8295] [ 3246.203001][ T8295] Freed by task 8199: [ 3246.207011][ T8295] kasan_save_stack+0x33/0x60 [ 3246.211840][ T8295] kasan_save_track+0x14/0x30 [ 3246.216587][ T8295] kasan_save_free_info+0x3b/0x60 [ 3246.221674][ T8295] __kasan_slab_free+0x51/0x70 [ 3246.226594][ T8295] kfree+0x14f/0x4b0 [ 3246.230547][ T8295] kvfree+0x47/0x50 [ 3246.234426][ T8295] rhashtable_free_and_destroy+0x16c/0x990 [ 3246.240316][ T8295] nfsd_file_cache_init+0x3e0/0x4d0 [ 3246.245587][ T8295] nfsd_svc+0x5db/0x940 [ 3246.249802][ T8295] nfsd_nl_threads_set_doit+0x535/0xbe0 [ 3246.255425][ T8295] genl_family_rcv_msg_doit+0x202/0x2f0 [ 3246.261048][ T8295] genl_rcv_msg+0x565/0x800 [ 3246.265634][ T8295] netlink_rcv_skb+0x165/0x410 [ 3246.270463][ T8295] genl_rcv+0x28/0x40 [ 3246.274539][ T8295] netlink_unicast+0x53c/0x7f0 [ 3246.279369][ T8295] netlink_sendmsg+0x8b8/0xd70 [ 3246.284200][ T8295] ____sys_sendmsg+0x9ae/0xb40 [ 3246.289023][ T8295] ___sys_sendmsg+0x135/0x1e0 [ 3246.293760][ T8295] __sys_sendmsg+0x117/0x1f0 [ 3246.298430][ T8295] do_syscall_64+0xcd/0x250 [ 3246.303005][ T8295] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 3246.308966][ T8295] [ 3246.311330][ T8295] The buggy address belongs to the object at ffff8880301ac000 [ 3246.311330][ T8295] which belongs to the cache kmalloc-4k of size 4096 [ 3246.325434][ T8295] The buggy address is located 16 bytes inside of [ 3246.325434][ T8295] freed 4096-byte region [ffff8880301ac000, ffff8880301ad000) [ 3246.339289][ T8295] [ 3246.341654][ T8295] The buggy address belongs to the physical page: [ 3246.348116][ T8295] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x301a8 [ 3246.356987][ T8295] head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 3246.365630][ T8295] flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) [ 3246.373252][ T8295] page_type: f5(slab) [ 3246.377291][ T8295] raw: 00fff00000000040 ffff88801ac42140 ffffea0000db9800 dead000000000002 [ 3246.385938][ T8295] raw: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000 [ 3246.394589][ T8295] head: 00fff00000000040 ffff88801ac42140 ffffea0000db9800 dead000000000002 [ 3246.403325][ T8295] head: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000 [ 3246.412047][ T8295] head: 00fff00000000003 ffffea0000c06a01 ffffffffffffffff 0000000000000000 [ 3246.420777][ T8295] head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 [ 3246.429501][ T8295] page dumped because: kasan: bad access detected [ 3246.435995][ T8295] page_owner tracks the page as allocated [ 3246.441746][ T8295] page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 21493, tgid 21493 (syz.0.3187), ts 1292101106947, free_ts 1292053895765 [ 3246.462737][ T8295] post_alloc_hook+0x2d1/0x350 [ 3246.467575][ T8295] get_page_from_freelist+0x101e/0x3070 [ 3246.473199][ T8295] __alloc_pages_noprof+0x223/0x25c0 [ 3246.478567][ T8295] alloc_pages_mpol_noprof+0x2c9/0x610 [ 3246.484105][ T8295] new_slab+0x2ba/0x3f0 [ 3246.488335][ T8295] ___slab_alloc+0xd1d/0x16f0 [ 3246.493128][ T8295] __slab_alloc.constprop.0+0x56/0xb0 [ 3246.498579][ T8295] __kmalloc_noprof+0x379/0x410 [ 3246.503511][ T8295] tomoyo_realpath_from_path+0xbf/0x710 [ 3246.509162][ T8295] tomoyo_check_open_permission+0x2a7/0x3b0 [ 3246.515145][ T8295] tomoyo_file_open+0xcf/0x100 [ 3246.519975][ T8295] security_file_open+0x64c/0x9d0 [ 3246.525092][ T8295] do_dentry_open+0x57c/0x1530 [ 3246.530014][ T8295] vfs_open+0x82/0x3f0 [ 3246.534177][ T8295] path_openat+0x1e6a/0x2d60 [ 3246.538831][ T8295] do_filp_open+0x1dc/0x430 [ 3246.543412][ T8295] page last free pid 12198 tgid 12198 stack trace: [ 3246.549952][ T8295] free_unref_page+0x5f4/0xdc0 [ 3246.554884][ T8295] __put_partials+0x14c/0x170 [ 3246.559637][ T8295] qlist_free_all+0x4e/0x120 [ 3246.564302][ T8295] kasan_quarantine_reduce+0x192/0x1e0 [ 3246.569924][ T8295] __kasan_slab_alloc+0x69/0x90 [ 3246.574848][ T8295] kmem_cache_alloc_node_noprof+0x153/0x310 [ 3246.580821][ T8295] __alloc_skb+0x2b3/0x380 [ 3246.585351][ T8295] alloc_skb_with_frags+0xe4/0x850 [ 3246.590526][ T8295] sock_alloc_send_pskb+0x7f1/0x980 [ 3246.595806][ T8295] mld_newpack.isra.0+0x1d4/0x7e0 [ 3246.600904][ T8295] add_grhead+0x299/0x340 [ 3246.605299][ T8295] add_grec+0x111e/0x1670 [ 3246.609696][ T8295] mld_ifc_work+0x41f/0xca0 [ 3246.614273][ T8295] process_one_work+0x958/0x1b30 [ 3246.619294][ T8295] worker_thread+0x6c8/0xf00 [ 3246.623964][ T8295] kthread+0x2c1/0x3a0 [ 3246.628104][ T8295] [ 3246.630461][ T8295] Memory state around the buggy address: [ 3246.636132][ T8295] ffff8880301abf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 3246.644246][ T8295] ffff8880301abf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 3246.652375][ T8295] >ffff8880301ac000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 3246.660488][ T8295] ^ [ 3246.665151][ T8295] ffff8880301ac080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 3246.673265][ T8295] ffff8880301ac100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 3246.681390][ T8295] ==================================================================
