mailmap: do not respect symlinks for in-tree .mailmap

As with .gitattributes and .gitignore, we would like to make sure that
.mailmap files are handled consistently whether read from the a blob (as
is the default behavior in a bare repo) or from the filesystem.
Likewise, we would like to avoid reading out-of-tree files pointed to by
a symlink, which could have security implications in certain setups.

We can cover both by using open_nofollow() when opening the in-tree
files. We'll continue to follow links for mailmap.file, as well as when
reading .mailmap from the current directory when outside of a repository
entirely.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Jeff King 2021-02-16 09:44:37 -05:00 committed by Junio C Hamano
parent feb9b7792f
commit adcd9f5472
2 changed files with 48 additions and 5 deletions

View File

@ -157,20 +157,30 @@ static void read_mailmap_line(struct string_list *map, char *buffer)
add_mapping(map, name1, email1, name2, email2);
}
static int read_mailmap_file(struct string_list *map, const char *filename)
/* Flags for read_mailmap_file() */
#define MAILMAP_NOFOLLOW (1<<0)
static int read_mailmap_file(struct string_list *map, const char *filename,
unsigned flags)
{
char buffer[1024];
FILE *f;
int fd;
if (!filename)
return 0;
f = fopen(filename, "r");
if (!f) {
if (flags & MAILMAP_NOFOLLOW)
fd = open_nofollow(filename, O_RDONLY);
else
fd = open(filename, O_RDONLY);
if (fd < 0) {
if (errno == ENOENT)
return 0;
return error_errno("unable to open mailmap at %s", filename);
}
f = xfdopen(fd, "r");
while (fgets(buffer, sizeof(buffer), f) != NULL)
read_mailmap_line(map, buffer);
@ -225,10 +235,12 @@ int read_mailmap(struct string_list *map)
if (!git_mailmap_blob && is_bare_repository())
git_mailmap_blob = "HEAD:.mailmap";
err |= read_mailmap_file(map, ".mailmap");
err |= read_mailmap_file(map, ".mailmap",
startup_info->have_repository ?
MAILMAP_NOFOLLOW : 0);
if (startup_info->have_repository)
err |= read_mailmap_blob(map, git_mailmap_blob);
err |= read_mailmap_file(map, git_mailmap_file);
err |= read_mailmap_file(map, git_mailmap_file, 0);
return err;
}

View File

@ -889,4 +889,35 @@ test_expect_success 'empty syntax: setup' '
test_cmp expect actual
'
test_expect_success SYMLINKS 'set up symlink tests' '
git commit --allow-empty -m foo --author="Orig <orig@example.com>" &&
echo "New <new@example.com> <orig@example.com>" >map &&
rm -f .mailmap
'
test_expect_success SYMLINKS 'symlinks respected in mailmap.file' '
test_when_finished "rm symlink" &&
ln -s map symlink &&
git -c mailmap.file="$(pwd)/symlink" log -1 --format=%aE >actual &&
echo "new@example.com" >expect &&
test_cmp expect actual
'
test_expect_success SYMLINKS 'symlinks respected in non-repo shortlog' '
git log -1 >input &&
test_when_finished "nongit rm .mailmap" &&
nongit ln -sf "$TRASH_DIRECTORY/map" .mailmap &&
nongit git shortlog -s <input >actual &&
echo " 1 New" >expect &&
test_cmp expect actual
'
test_expect_success SYMLINKS 'symlinks not respected in-tree' '
test_when_finished "rm .mailmap" &&
ln -s map .mailmap &&
git log -1 --format=%aE >actual &&
echo "orig@example.com" >expect&&
test_cmp expect actual
'
test_done