Actually there is one waiting in state flush_work, one in call_rwsem_down_read_failed and 12 in call_rwsem_down_write_failed.
The "flush_work" task call trace genesplicer D 0 53332 52566 0x00000000 Call Trace: __schedule+0x291/0x8a0 ? __switch_to_asm+0x40/0x70 ? get_work_pool+0x40/0x40 schedule+0x2c/0x80 schedule_timeout+0x1cf/0x350 ? sched_clock+0x9/0x10 ? sched_clock+0x9/0x10 ? sched_clock_cpu+0x11/0xb0 ? get_work_pool+0x40/0x40 wait_for_completion+0xba/0x140 ? wake_up_q+0x80/0x80 flush_work+0x126/0x1e0 ? worker_detach_from_pool+0xa0/0xa0 __cancel_work_timer+0x131/0x1b0 cancel_work_sync+0x10/0x20 cifsFileInfo_put+0x1ab/0x400 [cifs] cifs_close+0x1e/0x40 [cifs] ? cifs_close+0x1e/0x40 [cifs] __fput+0xea/0x220 ____fput+0xe/0x10 task_work_run+0x9d/0xc0 exit_to_usermode_loop+0xc0/0xd0 do_syscall_64+0x115/0x130 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x14f9e4ecf947 RSP: 002b:00007ffe591c9898 EFLAGS: 00000206 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 000056367a99e260 RCX: 000014f9e4ecf947 RDX: 000014f9e51a6760 RSI: 0000000000000001 RDI: 000000000000000b RBP: 000014f9e51a72a0 R08: 000014f9e53c14c0 R09: 0000000000000000 R10: 000014f9e4f5dcc0 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffe592be0a0 R14: 0000000000000000 R15: 0000000000000000 -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1824981 Title: cifs set_oplock buffer overflow in strcat Status in linux package in Ubuntu: Confirmed Bug description: Ubuntu 18.04.2 LTS Linux SRV013 4.15.0-47-generic #50-Ubuntu SMP Wed Mar 13 10:44:52 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux DELL R740, 2 CPU (40 Cores, 80 Threads), 384 GiB RAM top - 12:39:53 up 3:41, 4 users, load average: 66.19, 64.06, 76.90 Tasks: 1076 total, 1 running, 675 sleeping, 12 stopped, 1 zombie %Cpu(s): 28.2 us, 0.3 sy, 0.0 ni, 71.5 id, 0.0 wa, 0.0 hi, 0.1 si, 0.0 st KiB Mem : 39483801+total, 24077185+free, 57428284 used, 96637872 buff/cache KiB Swap: 999420 total, 999420 free, 0 used. 33477683+avail Mem We've seen the following bug many times since we introduced new machines running Ubuntu 18. Wasn't an issue older machines running Ubuntu 16. Three different machines are affected, so it's rather not a hardware issue. | detected buffer overflow in strcat | ------------[ cut here ]------------ | kernel BUG at /build/linux-6ZmFRN/linux-4.15.0/lib/string.c:1052! | invalid opcode: 0000 [#1] SMP PTI | Modules linked in: [...] | Hardware name: Dell Inc. PowerEdge R740/0923K0, BIOS 1.6.11 11/20/2018 | RIP: 0010:fortify_panic+0x13/0x22 | [...] | Call Trace: | smb21_set_oplock_level+0x147/0x1a0 [cifs] | smb3_set_oplock_level+0x22/0x90 [cifs] | smb2_set_fid+0x76/0xb0 [cifs] | cifs_new_fileinfo+0x259/0x390 [cifs] | ? smb2_get_lease_key+0x40/0x40 [cifs] | ? cifs_new_fileinfo+0x259/0x390 [cifs] | cifs_open+0x3db/0x8d0 [cifs] | [...] (Full dmesg output attached) After hitting this bug there are many cifs related dmesg entries, processes lock up and eventually the systems freezes. The share is mounted using: //server/share /mnt/server/ cifs defaults,auto,iocharset=utf8,noperm,file_mode=0777,dir_mode=0777,credentials=/root/passwords/share,domain=myDomain,uid=myUser,gid=10513,mfsymlinks Currently we're testing the cifs mount options "cache=none" as the bug seems to be oplock related. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1824981/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
