Created attachment 9083 [details] full backtrace from this PANIC I am running Samba 4.0.6 as an AD DC on two Ubuntu 12.04 servers, dc0 (which currently holds the FSMO roles) and dc1. Replication occurs between the two DCs. Recently, samba on dc0 has started PANICing fairly frequently with this error in the syslog: Jul 27 23:25:23 dc0 smbd[27824]: [2013/07/27 23:25:23.081517, 0] ../lib/util/fault.c:72(fault_report) Jul 27 23:25:23 dc0 smbd[27824]: =============================================================== Jul 27 23:25:23 dc0 smbd[27824]: [2013/07/27 23:25:23.082650, 0] ../lib/util/fault.c:73(fault_report) Jul 27 23:25:23 dc0 smbd[27824]: INTERNAL ERROR: Signal 11 in pid 27824 (4.0.6-Debian) Jul 27 23:25:23 dc0 smbd[27824]: Please read the Trouble-Shooting section of the Samba HOWTO Jul 27 23:25:23 dc0 smbd[27824]: [2013/07/27 23:25:23.082767, 0] ../lib/util/fault.c:75(fault_report) Jul 27 23:25:23 dc0 smbd[27824]: =============================================================== Jul 27 23:25:23 dc0 smbd[27824]: [2013/07/27 23:25:23.082828, 0] ../source3/lib/util.c:810(smb_panic_s3) Jul 27 23:25:23 dc0 smbd[27824]: PANIC (pid 27824): internal error Jul 27 23:25:23 dc0 smbd[27824]: [2013/07/27 23:25:23.083881, 0] ../source3/lib/util.c:921(log_stack_trace) Jul 27 23:25:23 dc0 smbd[27824]: BACKTRACE: 30 stack frames: Jul 27 23:25:23 dc0 smbd[27824]: #0 /usr/lib/x86_64-linux-gnu/libsmbconf.so.0(log_stack_trace+0x1a) [0x7f8b63ea307a] Jul 27 23:25:23 dc0 smbd[27824]: #1 /usr/lib/x86_64-linux-gnu/libsmbconf.so.0(smb_panic_s3+0x22) [0x7f8b63ea3152] Jul 27 23:25:23 dc0 smbd[27824]: #2 /usr/lib/x86_64-linux-gnu/libsamba-util.so.0(smb_panic+0x2f) [0x7f8b653a94bf] Jul 27 23:25:23 dc0 smbd[27824]: #3 /usr/lib/x86_64-linux-gnu/libsamba-util.so.0(+0x1a6d8) [0x7f8b653a96d8] Jul 27 23:25:23 dc0 smbd[27824]: #4 /lib/x86_64-linux-gnu/libpthread.so.0(+0xfcb0) [0x7f8b655cecb0] Jul 27 23:25:23 dc0 smbd[27824]: #5 /usr/lib/x86_64-linux-gnu/samba/libdfs_server_ad.so(+0x1412) [0x7f8b61888412] Jul 27 23:25:23 dc0 smbd[27824]: #6 /usr/lib/x86_64-linux-gnu/samba/libdfs_server_ad.so(+0x1985) [0x7f8b61888985] Jul 27 23:25:23 dc0 smbd[27824]: #7 /usr/lib/x86_64-linux-gnu/samba/libdfs_server_ad.so(dfs_server_ad_get_referrals+0xa82) [0x7f8b61889aa2] Jul 27 23:25:23 dc0 smbd[27824]: #8 /usr/lib/x86_64-linux-gnu/samba/libsmbd_base.so(+0x16b98c) [0x7f8b6501198c] Jul 27 23:25:23 dc0 smbd[27824]: #9 /usr/lib/x86_64-linux-gnu/samba/libsmbd_base.so(smb_vfs_call_get_dfs_referrals+0x2a) [0x7f8b64fa17ea] Jul 27 23:25:23 dc0 smbd[27824]: #10 /usr/lib/x86_64-linux-gnu/samba/libsmbd_base.so(setup_dfs_referral+0xa6) [0x7f8b64fc2926] Jul 27 23:25:23 dc0 smbd[27824]: #11 /usr/lib/x86_64-linux-gnu/samba/libsmbd_base.so(smbd_smb2_request_process_ioctl+0xab8) [0x7f8b64fd9018] Jul 27 23:25:23 dc0 smbd[27824]: #12 /usr/lib/x86_64-linux-gnu/samba/libsmbd_base.so(smbd_smb2_request_dispatch+0xc69) [0x7f8b64fcb439] Jul 27 23:25:23 dc0 smbd[27824]: #13 /usr/lib/x86_64-linux-gnu/samba/libsmbd_base.so(+0x1259b1) [0x7f8b64fcb9b1] Jul 27 23:25:23 dc0 smbd[27824]: #14 /usr/lib/x86_64-linux-gnu/samba/libsmbd_base.so(+0x1224d6) [0x7f8b64fc84d6] Jul 27 23:25:23 dc0 smbd[27824]: #15 /usr/lib/x86_64-linux-gnu/samba/libsamba-sockets.so(+0xa1e2) [0x7f8b63c751e2] Jul 27 23:25:23 dc0 smbd[27824]: #16 /usr/lib/x86_64-linux-gnu/samba/libsamba-sockets.so(+0x9cb4) [0x7f8b63c74cb4] Jul 27 23:25:23 dc0 smbd[27824]: #17 /usr/lib/x86_64-linux-gnu/samba/libsamba-sockets.so(+0x8bb4) [0x7f8b63c73bb4] Jul 27 23:25:23 dc0 smbd[27824]: #18 /usr/lib/x86_64-linux-gnu/libtevent.so.0(tevent_common_loop_immediate+0xe2) [0x7f8b62899dc2] Jul 27 23:25:23 dc0 smbd[27824]: #19 /usr/lib/x86_64-linux-gnu/libsmbconf.so.0(run_events_poll+0x48) [0x7f8b63eba148] Jul 27 23:25:23 dc0 smbd[27824]: #20 /usr/lib/x86_64-linux-gnu/libsmbconf.so.0(+0x3843b) [0x7f8b63eba43b] Jul 27 23:25:23 dc0 smbd[27824]: #21 /usr/lib/x86_64-linux-gnu/libtevent.so.0(_tevent_loop_once+0x9d) [0x7f8b6289950d] Jul 27 23:25:23 dc0 smbd[27824]: #22 /usr/lib/x86_64-linux-gnu/samba/libsmbd_base.so(smbd_process+0xa7e) [0x7f8b64fb657e] Jul 27 23:25:23 dc0 smbd[27824]: #23 /usr/sbin/smbd() [0x4096a4] Jul 27 23:25:23 dc0 smbd[27824]: #24 /usr/lib/x86_64-linux-gnu/libsmbconf.so.0(run_events_poll+0x294) [0x7f8b63eba394] Jul 27 23:25:23 dc0 smbd[27824]: #25 /usr/lib/x86_64-linux-gnu/libsmbconf.so.0(+0x384e8) [0x7f8b63eba4e8] Jul 27 23:25:23 dc0 smbd[27824]: #26 /usr/lib/x86_64-linux-gnu/libtevent.so.0(_tevent_loop_once+0x9d) [0x7f8b6289950d] Jul 27 23:25:23 dc0 smbd[27824]: #27 /usr/sbin/smbd(main+0x1200) [0x406670] Jul 27 23:25:23 dc0 smbd[27824]: #28 /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed) [0x7f8b624f876d] Jul 27 23:25:23 dc0 smbd[27824]: #29 /usr/sbin/smbd() [0x406b69] Jul 27 23:25:23 dc0 smbd[27824]: [2013/07/27 23:25:23.085784, 0] ../source3/lib/dumpcore.c:317(dump_core) Jul 27 23:25:23 dc0 smbd[27824]: dumping core in /var/log/samba/cores/smbd I have attached a full backtrace (with debug symbols) from the core dump. I think that Samba is actually restarting whatever is failing when this happens, as it is still running after this error occurs, and then this error appears again in the syslog within a few minutes or up to a couple hours. At first glance, this appears to be very similar to #10004, however I believe it to be a different problem since the backtrace differs widely. I have also attached the compile options I used, as well as my smb.conf file. Any ideas on what is causing this, or how to resolve/debug it? Thanks!
Created attachment 9084 [details] compile options used when building samba
Created attachment 9085 [details] smb.conf
Created attachment 9086 [details] patch to use dsdb_search_one to avoid this crash Can you try this patch?
A bit more debug: it appears that after this PANIC happens, group policy is not applied from this DC until samba is manually restarted. (In reply to comment #3) > Created attachment 9086 [details] > patch to use dsdb_search_one to avoid this crash > > Can you try this patch? The patch you provided appears to resolve this bug! :) Thanks a lot for the help!
Comment on attachment 9086 [details] patch to use dsdb_search_one to avoid this crash I was having the same problem and this patch has fixed it for me. I was epxeriencing this crash starting with 4.0.9, also in 4.0.10 and 4.1.0.
Comment on attachment 9086 [details] patch to use dsdb_search_one to avoid this crash Metze, Can you add my sign-off and review this into master?
Comment on attachment 9086 [details] patch to use dsdb_search_one to avoid this crash This looks good. Andrew can you push it to master with my review?
Comment on attachment 9086 [details] patch to use dsdb_search_one to avoid this crash This is already in master as commit 859182da6d06be0e9d37d7ed3448efc3dc78bdb2
Created attachment 9290 [details] Patch for v4-1-test
Created attachment 9291 [details] Patch for v4-0-test
Pushed to autobuild-v4-1-test and autobuild-v4-0-test.
Pushed to v4-1-test and v4-0-test. Closing out bug report. Thanks!