diff options
authorVasil Dimov <>2020-04-15 20:32:24 (GMT)
committerJunio C Hamano <>2020-04-16 01:32:47 (GMT)
commit8cf51561d1e15e8f5ad907df00884a7596737dcd (patch)
parentde49261b050d9cd8ec73842356077bc5b606640f (diff)
range-diff: fix a crash in parsing git-log output
`git range-diff` calls `git log` internally and tries to parse its output. But `git log` output can be customized by the user in their git config and for certain configurations either an error will be returned by `git range-diff` or it will crash. To fix this explicitly set the output format of the internally executed `git log` with `--pretty=medium`. Because that cancels `--notes`, add explicitly `--notes` at the end. Also, make sure we never crash in the same way - trying to dereference `util` which was never created and has remained NULL. It would happen if the first line of `git log` output does not begin with 'commit '. Alternative considered but discarded - somehow disable all git configs and behave as if no config is present in the internally executed `git log`, but that does not seem to be possible. GIT_CONFIG_NOSYSTEM is the closest to it, but even with that we would still read `.git/config`. Signed-off-by: Vasil Dimov <> Signed-off-by: Junio C Hamano <>
2 files changed, 23 insertions, 0 deletions
diff --git a/range-diff.c b/range-diff.c
index f745567..5cc920b 100644
--- a/range-diff.c
+++ b/range-diff.c
@@ -63,6 +63,8 @@ static int read_patches(const char *range, struct string_list *list,
+ "--pretty=medium",
+ "--notes",
if (other_arg)
argv_array_pushv(&cp.args, other_arg->argv);
@@ -106,6 +108,17 @@ static int read_patches(const char *range, struct string_list *list,
+ if (!util) {
+ error(_("could not parse first line of `log` output: "
+ "did not start with 'commit ': '%s'"),
+ line);
+ string_list_clear(list, 1);
+ strbuf_release(&buf);
+ strbuf_release(&contents);
+ finish_command(&cp);
+ return -1;
+ }
if (starts_with(line, "diff --git")) {
struct patch patch = { 0 };
struct strbuf root = STRBUF_INIT;
diff --git a/t/ b/t/
index bd808f8..e024cff 100755
--- a/t/
+++ b/t/
@@ -513,6 +513,16 @@ test_expect_success 'range-diff overrides diff.noprefix internally' '
git -c diff.noprefix=true range-diff HEAD^...
+test_expect_success 'basic with modified format.pretty with suffix' '
+ git -c format.pretty="format:commit %H%d%n" range-diff \
+ master..topic master..unmodified
+test_expect_success 'basic with modified format.pretty without "commit "' '
+ git -c format.pretty="format:%H%n" range-diff \
+ master..topic master..unmodified
test_expect_success 'range-diff compares notes by default' '
git notes add -m "topic note" topic &&
git notes add -m "unmodified note" unmodified &&