Don't permit ref/branch names to end with ".lock"

We already skip over loose refs under $GIT_DIR/refs if the name ends with ".lock", so creating a branch named "foo.lock" will not appear in the output of "git branch", "git for-each-ref", nor will its commit be considered reachable by "git rev-list --all". In the latter case this is especially evil, as it may cause repository corruption when objects reachable only through such a ref are deleted by "git prune". It should be reasonably safe to deny use of ".lock" as a ref suffix. In prior versions of Git such branches would be "phantom branches"; you can create it, but you can't see it in "git branch" output. Signed-off-by: Shawn O. Pearce <spearce@spearce.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Shawn O. Pearce committed Mar 24, 2009 at 16:31 UTC 3e262b95c50991de12cc5e180b72256561606a19

2 files changed +5

Documentation/git-check-ref-format.txt

@@ -34,6 +34,8 @@ imposes the following rules on how refs are named:

35 . They cannot end with a slash `/` nor a dot `.`.

37 +. They cannot end with the sequence `.lock`.

38 +

39 . They cannot contain a sequence `@{`.

41 These rules makes it easy for shell script based tools to parse

refs.c

@@ -676,6 +676,7 @@ int for_each_rawref(each_ref_fn fn, void *cb_data)

676 * - it has double dots "..", or

677 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or

678 * - it ends with a "/".

679 + * - it ends with ".lock"

680 */

681

682 static inline int bad_ref_char(int ch)

@@ -737,6 +738,8 @@ int check_ref_format(const char *ref)

738 return CHECK_REF_FORMAT_ERROR;

739 if (level < 2)

740 return CHECK_REF_FORMAT_ONELEVEL;

741 + if (has_extension(ref, ".lock"))

742 + return CHECK_REF_FORMAT_ERROR;

743 return ret;

744 }

745 }