On Wed, Sep 18, 2024 at 09:26:27AM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 57719771a244 Merge tag 'sound-6.11' of git://git.kernel.or.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=122c17c7980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=96be9a618e50f19f > dashboard link: https://syzkaller.appspot.com/bug?extid=6926ab9f6f7d7b50002e > compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1559749f980000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1359749f980000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/87498efcab61/disk-57719771.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/5703d19e746c/vmlinux-57719771.xz > kernel image: https://storage.googleapis.com/syzbot-assets/3744ba66862a/bzImage-57719771.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+6926ab9f6f7d7b50002e@xxxxxxxxxxxxxxxxxxxxxxxxx > > svc: failed to register nfsdv3 RPC service (errno 512). > svc: failed to register nfsaclv3 RPC service (errno 512). > ================================================================== > BUG: KASAN: slab-use-after-free in shrinker_free+0x3b7/0x430 mm/shrinker.c:775 > Read of size 4 at addr ffff8880206cbb1c by task syz-executor313/5320 > > CPU: 0 UID: 0 PID: 5320 Comm: syz-executor313 Not tainted 6.11.0-rc7-syzkaller-00145-g57719771a244 #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 > shrinker_free+0x3b7/0x430 mm/shrinker.c:775 > nfsd_file_cache_shutdown+0xbc/0x480 fs/nfsd/filecache.c:891 > 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 This looks like an issue with nfsd startup error handling (maybe resulting in a double free?) and not a shrinker issue as such. CC'ing the NFS people. -Dave. > 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+0x9b4/0xb50 net/socket.c:2597 > ___sys_sendmsg+0x135/0x1e0 net/socket.c:2651 > __sys_sendmsg+0x117/0x1f0 net/socket.c:2680 > 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: 0033:0x7f51ae6e5ab9 > Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 1d 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:00007f51ae634158 EFLAGS: 00000246 ORIG_RAX: 000000000000002e > RAX: ffffffffffffffda RBX: 00007f51ae768438 RCX: 00007f51ae6e5ab9 > RDX: 0000000000000004 RSI: 0000000020000280 RDI: 0000000000000003 > RBP: 00007f51ae768430 R08: 0000000000000008 R09: 0000000000000000 > R10: 0000000000000003 R11: 0000000000000246 R12: 00007f51ae76843c > R13: 000000000000006e R14: 00007ffc1415e4a0 R15: 00007ffc1415e588 > </TASK> > > Allocated by task 5309: > 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 > kmalloc_noprof include/linux/slab.h:681 [inline] > kzalloc_noprof include/linux/slab.h:807 [inline] > shrinker_alloc+0xf8/0xb00 mm/shrinker.c:683 > nfsd_file_cache_init+0x152/0x450 fs/nfsd/filecache.c:743 > nfsd_startup_generic fs/nfsd/nfssvc.c:307 [inline] > nfsd_startup_net fs/nfsd/nfssvc.c:402 [inline] > nfsd_svc+0x542/0x970 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+0x9b4/0xb50 net/socket.c:2597 > ___sys_sendmsg+0x135/0x1e0 net/socket.c:2651 > __sys_sendmsg+0x117/0x1f0 net/socket.c:2680 > 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 > > Freed by task 0: > 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:2256 [inline] > slab_free mm/slub.c:4477 [inline] > kfree+0x12a/0x3b0 mm/slub.c:4598 > rcu_do_batch kernel/rcu/tree.c:2569 [inline] > rcu_core+0x828/0x16b0 kernel/rcu/tree.c:2843 > handle_softirqs+0x216/0x8f0 kernel/softirq.c:554 > __do_softirq kernel/softirq.c:588 [inline] > invoke_softirq kernel/softirq.c:428 [inline] > __irq_exit_rcu kernel/softirq.c:637 [inline] > irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649 > instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] > sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 > asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 > > Last potentially related work creation: > kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 > __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:541 > __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:3106 > shrinker_free+0xfe/0x430 mm/shrinker.c:807 > nfsd_file_cache_shutdown+0xbc/0x480 fs/nfsd/filecache.c:891 > 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+0x9b4/0xb50 net/socket.c:2597 > ___sys_sendmsg+0x135/0x1e0 net/socket.c:2651 > __sys_sendmsg+0x117/0x1f0 net/socket.c:2680 > 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 > > The buggy address belongs to the object at ffff8880206cbb00 > which belongs to the cache kmalloc-192 of size 192 > The buggy address is located 28 bytes inside of > freed 192-byte region [ffff8880206cbb00, ffff8880206cbbc0) > > The buggy address belongs to the physical page: > page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x206cb > flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) > page_type: 0xfdffffff(slab) > raw: 00fff00000000000 ffff88801ac413c0 dead000000000100 dead000000000122 > raw: 0000000000000000 0000000080100010 00000001fdffffff 0000000000000000 > page dumped because: kasan: bad access detected > page_owner tracks the page as allocated > page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 4560085887, free_ts 0 > 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:2325 > allocate_slab mm/slub.c:2488 [inline] > new_slab+0x84/0x260 mm/slub.c:2541 > ___slab_alloc+0xdac/0x1870 mm/slub.c:3727 > __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3817 > __slab_alloc_node mm/slub.c:3870 [inline] > slab_alloc_node mm/slub.c:4029 [inline] > __kmalloc_cache_noprof+0x2c5/0x310 mm/slub.c:4188 > kmalloc_noprof include/linux/slab.h:681 [inline] > kzalloc_noprof include/linux/slab.h:807 [inline] > call_usermodehelper_setup+0x9a/0x340 kernel/umh.c:363 > kobject_uevent_env+0xde3/0x1670 lib/kobject_uevent.c:628 > kset_register+0x1b6/0x2b0 lib/kobject.c:877 > class_register+0x22e/0x340 drivers/base/class.c:203 > typec_init+0x63/0x110 drivers/usb/typec/class.c:2518 > do_one_initcall+0x128/0x630 init/main.c:1267 > do_initcall_level init/main.c:1329 [inline] > do_initcalls init/main.c:1345 [inline] > do_basic_setup init/main.c:1364 [inline] > kernel_init_freeable+0x660/0xc50 init/main.c:1578 > kernel_init+0x1c/0x2b0 init/main.c:1467 > page_owner free stack trace missing > > Memory state around the buggy address: > ffff8880206cba00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ffff8880206cba80: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc > >ffff8880206cbb00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ^ > ffff8880206cbb80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc > ffff8880206cbc00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ================================================================== > > > --- > 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 syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. > > 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 > -- Dave Chinner david@xxxxxxxxxxxxx
