On Tue, 1 Feb 2022 at 08:48, syzbot <syzbot+476bd1c816c8c9c340d7@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: 0280e3c58f92 Merge tag 'nfs-for-5.17-1' of git://git.linux.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=11b3dde4700000 > kernel config: https://syzkaller.appspot.com/x/.config?x=916d34c0d501b86 > dashboard link: https://syzkaller.appspot.com/bug?extid=476bd1c816c8c9c340d7 > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+476bd1c816c8c9c340d7@xxxxxxxxxxxxxxxxxxxxxxxxx There seems to be something with stacks reported by KASAN. The older report looked more consistent (matching stacks): https://syzkaller.appspot.com/bug?id=a2ca32319e8cd0cf8688611b1b69de781796d44e but looks like the same problem(?) BUG: KASAN: use-after-free in recv_work+0x2a2/0x2c0 drivers/block/nbd.c:787 Read of size 8 at addr ffff88801181ed20 by task kworker/u5:2/8465 CPU: 1 PID: 8465 Comm: kworker/u5:2 Not tainted 5.11.0-rc5-next-20210129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: knbd5-recv recv_work Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232 __kasan_report mm/kasan/report.c:399 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416 recv_work+0x2a2/0x2c0 drivers/block/nbd.c:787 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Allocated by task 17044: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:403 [inline] ____kasan_kmalloc mm/kasan/common.c:434 [inline] ____kasan_kmalloc.constprop.0+0xa0/0xd0 mm/kasan/common.c:406 kasan_slab_alloc include/linux/kasan.h:208 [inline] slab_post_alloc_hook mm/slab.h:516 [inline] slab_alloc_node mm/slub.c:2907 [inline] slab_alloc mm/slub.c:2915 [inline] __kmalloc_track_caller+0x16c/0x2e0 mm/slub.c:4550 __do_krealloc mm/slab_common.c:1149 [inline] krealloc+0x60/0xa0 mm/slab_common.c:1178 nbd_add_socket+0x263/0x6a0 drivers/block/nbd.c:1044 __nbd_ioctl drivers/block/nbd.c:1369 [inline] nbd_ioctl+0x388/0xa50 drivers/block/nbd.c:1425 blkdev_ioctl+0x2a1/0x6d0 block/ioctl.c:576 block_ioctl+0xf9/0x140 fs/block_dev.c:1650 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 17044: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357 ____kasan_slab_free.part.0+0xe1/0x110 mm/kasan/common.c:364 kasan_slab_free include/linux/kasan.h:191 [inline] slab_free_hook mm/slub.c:1562 [inline] slab_free_freelist_hook+0x82/0x1d0 mm/slub.c:1600 slab_free mm/slub.c:3161 [inline] kfree+0xe5/0x7b0 mm/slub.c:4202 krealloc+0x45/0xa0 mm/slab_common.c:1180 nbd_add_socket+0x263/0x6a0 drivers/block/nbd.c:1044 __nbd_ioctl drivers/block/nbd.c:1369 [inline] nbd_ioctl+0x388/0xa50 drivers/block/nbd.c:1425 blkdev_ioctl+0x2a1/0x6d0 block/ioctl.c:576 block_ioctl+0xf9/0x140 fs/block_dev.c:1650 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 > ================================================================== > BUG: KASAN: use-after-free in recv_work+0x840/0x8b0 drivers/block/nbd.c:863 > Read of size 8 at addr ffff88801886e9b0 by task kworker/u5:5/3653 > > CPU: 0 PID: 3653 Comm: kworker/u5:5 Not tainted 5.17.0-rc1-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Workqueue: nbd1-recv recv_work > Call Trace: > <TASK> > __dump_stack lib/dump_stack.c:88 [inline] > dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 > print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255 > __kasan_report mm/kasan/report.c:442 [inline] > kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 > recv_work+0x840/0x8b0 drivers/block/nbd.c:863 > process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 > worker_thread+0x657/0x1110 kernel/workqueue.c:2454 > kthread+0x2e9/0x3a0 kernel/kthread.c:377 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 > </TASK> > > Allocated by task 7763: > kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 > kasan_set_track mm/kasan/common.c:45 [inline] > set_alloc_info mm/kasan/common.c:436 [inline] > ____kasan_kmalloc mm/kasan/common.c:515 [inline] > ____kasan_kmalloc mm/kasan/common.c:474 [inline] > __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524 > kmalloc_node include/linux/slab.h:604 [inline] > __vmalloc_area_node mm/vmalloc.c:2948 [inline] > __vmalloc_node_range+0x444/0x1060 mm/vmalloc.c:3107 > __vmalloc_node mm/vmalloc.c:3157 [inline] > vzalloc+0x67/0x80 mm/vmalloc.c:3227 > do_ipt_get_ctl+0x60d/0x9d0 net/ipv4/netfilter/ip_tables.c:801 > nf_getsockopt+0x72/0xd0 net/netfilter/nf_sockopt.c:116 > ip_getsockopt net/ipv4/ip_sockglue.c:1786 [inline] > ip_getsockopt+0x164/0x1c0 net/ipv4/ip_sockglue.c:1765 > tcp_getsockopt+0x86/0xd0 net/ipv4/tcp.c:4284 > __sys_getsockopt+0x21f/0x5f0 net/socket.c:2224 > __do_sys_getsockopt net/socket.c:2239 [inline] > __se_sys_getsockopt net/socket.c:2236 [inline] > __x64_sys_getsockopt+0xba/0x150 net/socket.c:2236 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > > Freed by task 29418: > kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 > kasan_set_track+0x21/0x30 mm/kasan/common.c:45 > kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 > ____kasan_slab_free mm/kasan/common.c:366 [inline] > ____kasan_slab_free+0x130/0x160 mm/kasan/common.c:328 > kasan_slab_free include/linux/kasan.h:236 [inline] > slab_free_hook mm/slub.c:1728 [inline] > slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 > slab_free mm/slub.c:3509 [inline] > kfree+0xcb/0x280 mm/slub.c:4562 > krealloc+0x69/0xf0 mm/slab_common.c:1219 > nbd_add_socket+0x2cb/0x810 drivers/block/nbd.c:1130 > __nbd_ioctl drivers/block/nbd.c:1454 [inline] > nbd_ioctl+0x38c/0xb10 drivers/block/nbd.c:1511 > blkdev_ioctl+0x37a/0x800 block/ioctl.c:588 > vfs_ioctl fs/ioctl.c:51 [inline] > __do_sys_ioctl fs/ioctl.c:874 [inline] > __se_sys_ioctl fs/ioctl.c:860 [inline] > __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 > do_syscall_x64 arch/x86/entry/common.c:50 [inline] > do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 > entry_SYSCALL_64_after_hwframe+0x44/0xae > > The buggy address belongs to the object at ffff88801886e9b0 > which belongs to the cache kmalloc-8 of size 8 > The buggy address is located 0 bytes inside of > 8-byte region [ffff88801886e9b0, ffff88801886e9b8) > The buggy address belongs to the page: > page:ffffea0000621b80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1886e > flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) > raw: 00fff00000000200 ffffea0001d57400 dead000000000002 ffff888010c41280 > raw: 0000000000000000 0000000080660066 00000001ffffffff 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 0x12a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY), pid 3634, ts 181715914950, free_ts 181667651758 > prep_new_page mm/page_alloc.c:2434 [inline] > get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 > __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389 > alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271 > alloc_slab_page mm/slub.c:1799 [inline] > allocate_slab mm/slub.c:1944 [inline] > new_slab+0x28a/0x3b0 mm/slub.c:2004 > ___slab_alloc+0x87c/0xe90 mm/slub.c:3018 > __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105 > slab_alloc_node mm/slub.c:3196 [inline] > slab_alloc mm/slub.c:3238 [inline] > __kmalloc+0x2fb/0x340 mm/slub.c:4420 > kmalloc_array include/linux/slab.h:621 [inline] > kcalloc include/linux/slab.h:652 [inline] > nsim_fib6_event_init drivers/net/netdevsim/fib.c:807 [inline] > nsim_fib6_prepare_event drivers/net/netdevsim/fib.c:940 [inline] > nsim_fib_event_schedule_work drivers/net/netdevsim/fib.c:991 [inline] > nsim_fib_event_nb+0x2f1/0xc50 drivers/net/netdevsim/fib.c:1028 > call_fib_notifier+0x32/0x70 net/core/fib_notifier.c:24 > call_fib6_entry_notifier net/ipv6/ip6_fib.c:373 [inline] > fib6_rt_dump net/ipv6/ip6_fib.c:452 [inline] > fib6_node_dump+0x1c4/0x2d0 net/ipv6/ip6_fib.c:462 > fib6_walk_continue+0x3e9/0x6c0 net/ipv6/ip6_fib.c:2112 > fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2160 > fib6_table_dump net/ipv6/ip6_fib.c:474 [inline] > fib6_tables_dump+0x1dc/0x340 net/ipv6/ip6_fib.c:503 > fib6_dump+0x47/0x60 net/ipv6/fib6_notifier.c:39 > fib_net_dump net/core/fib_notifier.c:71 [inline] > register_fib_notifier+0x1fc/0x7b0 net/core/fib_notifier.c:109 > nsim_fib_create+0x7a5/0xa60 drivers/net/netdevsim/fib.c:1557 > page last free stack trace: > reset_page_owner include/linux/page_owner.h:24 [inline] > free_pages_prepare mm/page_alloc.c:1352 [inline] > free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 > free_unref_page_prepare mm/page_alloc.c:3325 [inline] > free_unref_page+0x19/0x690 mm/page_alloc.c:3404 > qlink_free mm/kasan/quarantine.c:157 [inline] > qlist_free_all+0x6d/0x160 mm/kasan/quarantine.c:176 > kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283 > __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446 > kasan_slab_alloc include/linux/kasan.h:260 [inline] > slab_post_alloc_hook mm/slab.h:732 [inline] > slab_alloc_node mm/slub.c:3230 [inline] > kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3266 > __alloc_skb+0x215/0x340 net/core/skbuff.c:414 > alloc_skb include/linux/skbuff.h:1158 [inline] > nlmsg_new include/net/netlink.h:953 [inline] > devlink_param_notify+0xba/0x230 net/core/devlink.c:4729 > devlink_notify_register net/core/devlink.c:9112 [inline] > devlink_register+0x398/0x4a0 net/core/devlink.c:9164 > nsim_drv_probe+0xd81/0x11c0 drivers/net/netdevsim/dev.c:1604 > call_driver_probe drivers/base/dd.c:517 [inline] > really_probe+0x245/0xcc0 drivers/base/dd.c:596 > __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:752 > driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:782 > __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:899 > bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427 > __device_attach+0x228/0x4a0 drivers/base/dd.c:970 > > Memory state around the buggy address: > ffff88801886e880: fc fc fc fa fc fc fc fc fa fc fc fc fc fb fc fc > ffff88801886e900: fc fc fa fc fc fc fc fa fc fc fc fc fa fc fc fc > >ffff88801886e980: fc fa fc fc fc fc fa fc fc fc fc fa fc fc fc fc > ^ > ffff88801886ea00: fa fc fc fc fc fa fc fc fc fc fb fc fc fc fc fa > ffff88801886ea80: fc fc fc fc fa fc fc fc fc fb fc fc fc fc fa fc > ================================================================== > > > --- > 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. > > -- > You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/00000000000008b80505d6f02054%40google.com.
