[Bug 1931391] Re: git bisect start crashed with SIGSEGV in buffer_slab_peek()

[Anatoly Pugachev]

$ dpkg -l git
||/ Name           Version              Architecture Description
+++-==============-====================-============-===================================================
ii  git            1:2.25.1-1ubuntu3.11 amd64        fast, scalable, distributed revision control system

$ gdb -q /usr/bin/git /tmp/core_git.691604
Reading symbols from /usr/bin/git...
Reading symbols from /usr/lib/debug/.build-id/35/7565dd8d992f17428ea299da06e82213052b9c.debug...
[New LWP 691604]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `git bisect--helper --bisect-start recipes/gtest/all/conandata.yml'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x000055b8b6ab22be in buffer_slab_peek (c=0x0, s=<optimized out>) at commit.c:290
290     commit.c: No such file or directory.
(gdb) bt
#0  0x000055b8b6ab22be in buffer_slab_peek (c=0x0, s=<optimized out>) at commit.c:290
#1  get_cached_commit_buffer (r=r at entry=0x55b8b6ce5680 <the_repo>, commit=commit at entry=0x0, sizep=sizep at entry=0x0) at commit.c:290
#2  0x000055b8b6ab231b in repo_get_commit_buffer (r=r at entry=0x55b8b6ce5680 <the_repo>, commit=commit at entry=0x0, sizep=sizep at entry=0x0) at commit.c:306
#3  0x000055b8b6b42835 in repo_logmsg_reencode (r=r at entry=0x55b8b6ce5680 <the_repo>, commit=commit at entry=0x0, commit_encoding=commit_encoding at entry=0x7ffff4c3e818,
    output_encoding=output_encoding at entry=0x55b8b6c075ba "UTF-8") at pretty.c:621
#4  0x000055b8b6b445c4 in repo_format_commit_message (r=0x55b8b6ce5680 <the_repo>, commit=commit at entry=0x0, format=format at entry=0x55b8b6c1a273 "%s",
    sb=sb at entry=0x7ffff4c3e910, pretty_ctx=pretty_ctx at entry=0x7ffff4c3e930) at pretty.c:1681
#5  0x000055b8b69de7b6 in log_commit (fmt=0x55b8b6c1a273 "%s", commit=0x0, state=0x55b8b7aa3710 "bad", fp=0x55b8b7a9da90) at builtin/bisect--helper.c:193
#6  bisect_write (state=0x55b8b7aa3710 "bad", rev=0x55b8b7aa3540 '0' <repeats 40 times>, nolog=nolog at entry=1, terms=<optimized out>, terms=<optimized out>)
    at builtin/bisect--helper.c:238
#7  0x000055b8b69df735 in bisect_start (argc=<optimized out>, argv=..., no_checkout=<optimized out>, terms=0x7ffff4c3ea70) at builtin/bisect--helper.c:590
#8  cmd_bisect__helper (argc=<optimized out>, argv=0x7ffff4c3f370, prefix=<optimized out>) at builtin/bisect--helper.c:708
#9  0x000055b8b69d4304 in run_builtin (argv=<optimized out>, argc=<optimized out>, p=<optimized out>) at git.c:444
#10 handle_builtin (argc=<optimized out>, argv=<optimized out>) at git.c:674
#11 0x000055b8b69d53d4 in run_argv (argv=0x7ffff4c3f0c0, argcp=0x7ffff4c3f0cc) at git.c:741
#12 cmd_main (argc=<optimized out>, argv=<optimized out>) at git.c:872
#13 0x000055b8b69d3e9e in main (argc=4, argv=0x7ffff4c3f368) at common-main.c:52
(gdb)

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to git in Ubuntu.
https://bugs.launchpad.net/bugs/1931391

Title:
  git bisect start crashed with SIGSEGV in buffer_slab_peek()

Status in git package in Ubuntu:
  Confirmed

Bug description:
  `git bisect start <filename>` always exits with a Segmentation fault.

  ProblemType: Crash
  DistroRelease: Ubuntu 20.04
  Package: git 1:2.25.1-1ubuntu3.1
  ProcVersionSignature: Ubuntu 5.4.0-65.73-generic 5.4.78
  Uname: Linux 5.4.0-65-generic x86_64
  ApportVersion: 2.20.11-0ubuntu27.18
  Architecture: amd64
  CasperMD5CheckResult: skip
  CurrentDesktop: XFCE
  Date: Wed Jun  9 11:24:04 2021
  ExecutablePath: /usr/bin/git
  InstallationDate: Installed on 2016-02-27 (1929 days ago)
  InstallationMedia: Xubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021)
  ProcCmdline: git bisect--helper --bisect-start synapse/storage/persist_events.py
  SegvAnalysis:
   Segfault happened at: 0x55d3ab6b0cde <get_cached_commit_buffer+14>:	mov    0x48(%rsi),%esi
   PC (0x55d3ab6b0cde) ok
   source "0x48(%rsi)" (0x00000048) not located in a known VMA region (needed readable region)!
   destination "%esi" ok
  SegvReason: reading NULL VMA
  Signal: 11
  SourcePackage: git
  StacktraceTop:
   buffer_slab_peek (c=0x0, s=<optimized out>) at commit.c:290
   get_cached_commit_buffer (r=r at entry=0x55d3ab8e0680 <the_repo>, commit=commit at entry=0x0, sizep=sizep at entry=0x0) at commit.c:290
   repo_get_commit_buffer (r=r at entry=0x55d3ab8e0680 <the_repo>, commit=commit at entry=0x0, sizep=sizep at entry=0x0) at commit.c:306
   repo_logmsg_reencode (r=r at entry=0x55d3ab8e0680 <the_repo>, commit=commit at entry=0x0, commit_encoding=commit_encoding at entry=0x7ffc63d83518, output_encoding=output_encoding at entry=0x55d3ab80257a "UTF-8") at pretty.c:614
   repo_format_commit_message (r=0x55d3ab8e0680 <the_repo>, commit=commit at entry=0x0, format=format at entry=0x55d3ab815233 "%s", sb=sb at entry=0x7ffc63d83610, pretty_ctx=pretty_ctx at entry=0x7ffc63d83630) at pretty.c:1640
  Title: git crashed with SIGSEGV in buffer_slab_peek()
  UpgradeStatus: Upgraded to focal on 2021-02-16 (112 days ago)
  UserGroups: adm cdrom dialout dip docker input libvirt libvirtd lpadmin plugdev sambashare sbuild sudo wireshark
  modified.conffile..etc.apport.crashdb.conf: [modified]
  mtime.conffile..etc.apport.crashdb.conf: 2021-06-09T11:10:35.636012
  separator:

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/git/+bug/1931391/+subscriptions