Re: format-patch crashes with a huge patchset
From: Junio C Hamano <hidden>
Date: 2016-06-15 23:01:16
Jeff King [off-list ref] writes:
On Mon, May 19, 2014 at 10:35:56PM +0300, Michael S. Tsirkin wrote:quoted
I tried to fump the whole history of qemu with format-patch. It crashes both with v2.0.0-rc2-21-g6087111 and with git 1.8.3.1: ~/opt/libexec/git-core/git-format-patch --follow -o patches/all e63c3dc74bfb90e4522d075d0d5a7600c5145745..You can't use "--follow" without specifying a single pathspec. Running "git log --follow" notices and blocks this, but format-patch doesn't (and segfaults later when the follow code assumes there is a pathspec). I think we need:
Looks sensible. Intrestingly enough, this dates all the way back to the original 750f7b66 (Finally implement "git log --follow", 2007-06-19). Re-reading the log message of that commit was amusing for other reasons, by the way (the most interesting part comes after "One thing to look out for:" and especially "Put another way:").
quoted hunk
-- >8 -- Subject: move "--follow needs one pathspec" rule to diff_setup_done Because of the way "--follow" is implemented, we must have exactly one pathspec. "git log" enforces this restriction, but other users of the revision traversal code do not. For example, "git format-patch --follow" will segfault during try_to_follow_renames, as we have no pathspecs at all. We can push this check down into diff_setup_done, which is probably a better place anyway. It is the diff code that introduces this restriction, so other parts of the code should not need to care themselves. Reported-by: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Jeff King <redacted> --- I didn't include a test, as I don't think the current behavior is what we want in the long run. That is, it would be nice if eventually --follow learned to be more flexible. Any test for this would necessarily be looking for the opposite of that behavior. But maybe it's worth it to just have in the meantime, and anyone who works on --follow can rip out the test. builtin/log.c | 8 ++------ diff.c | 3 +++ 2 files changed, 5 insertions(+), 6 deletions(-)diff --git a/builtin/log.c b/builtin/log.c index 39e8836..3b6a6bb 100644 --- a/builtin/log.c +++ b/builtin/log.c@@ -158,13 +158,9 @@ static void cmd_log_init_finish(int argc, const char **argv, const char *prefix, if (rev->show_notes) init_display_notes(&rev->notes_opt); - if (rev->diffopt.pickaxe || rev->diffopt.filter) + if (rev->diffopt.pickaxe || rev->diffopt.filter || + DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) rev->always_show_header = 0; - if (DIFF_OPT_TST(&rev->diffopt, FOLLOW_RENAMES)) { - rev->always_show_header = 0; - if (rev->diffopt.pathspec.nr != 1) - usage("git logs can only follow renames on one pathname at a time"); - } if (source) rev->show_source = 1;diff --git a/diff.c b/diff.c index f72769a..68bb8c5 100644 --- a/diff.c +++ b/diff.c@@ -3325,6 +3325,9 @@ void diff_setup_done(struct diff_options *options) } options->diff_path_counter = 0; + + if (DIFF_OPT_TST(options, FOLLOW_RENAMES) && options->pathspec.nr != 1) + die(_("--follow requires exactly one pathspec")); } static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)