Thank you for your further analyzation and explanation. I would love to make a patch for this bug, but sadly I'm not fully aware of what is going on in this functions and how they are affecting other git functionality. I hope @szeder can look into this bug and provide more explanation as he knows this code best. Best regards, Ondřej Pohořelský On Fri, Mar 6, 2020 at 3:58 PM Alexandr Miloslavskiy <alexandr.miloslavskiy@xxxxxxxxxxx> wrote: > > Since I like studying crashes and noone else replied, I decided to have > a look. > > The problem is easy to reproduce with this (replace 1.c with any file): > git log --follow -L 1,1:1.c -- 1.c > > It occurs because `opt->pathspec.items` gets cleaned here: > clear_pathspec > queue_diffs > /* must look at the full tree diff to detect renames */ > clear_pathspec(&opt->pathspec); > DIFF_QUEUE_CLEAR(&diff_queued_diff); > process_ranges_ordinary_commit > process_ranges_arbitrary_commit > line_log_filter > prepare_revision_walk > cmd_log_walk > cmd_log > > And on next iteration it crashes in 'try_to_follow_renames' on this line: > diff_opts.single_follow = opt->pathspec.items[0].match; > > I think that bug comes from commit: > a2bb801f by SZEDER Gábor, 2019-08-21 13:04:24 > line-log: avoid unnecessary full tree diffs > > @szeder could you please look into that? > > On 27.02.2020 13:56, Ondrej Pohorelsky wrote: > > Hi, > > > > there is a SIGSEGV appearing in Fedora[0] with Git 2.24.1 > > > > This bug started to appear after update to Git 2.24.1. > > Bug reporter said that Git crashed on him while running VS Code with > > Git Lens extension[1] > > I have tried to reproduce this bug with my own compiled Git with debug > > flags, but sadly SIGSEGV never appeared. > > > > To me it seems like there is a problem in commit a2bb801f6a[2] which > > changes move_diff_queue() function. This function calls > > diff_tree_oid() that calls try_to_follow_renames(). In the last two > > functions there are no arguments checks. > > > > Best regards, > > Ondřej Pohořelský > > > > [0] https://retrace.fedoraproject.org/faf/problems/bthash/?bth=25aa7d7267ab5de548ffca337115cb68f7b65105 > > [1] https://bugzilla.redhat.com/show_bug.cgi?id=1791810 > > [2] https://git.kernel.org/pub/scm/git/git.git/commit/?id=a2bb801f6a430f6049e5c9729a8f3bf9097d9b34 > > >
