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
