From: Nicolas Morey-Chaisemartin Date: Tue, 30 Aug 2011 13:45:38 +0000 (+0200) Subject: grep: Fix race condition in delta_base_cache X-Git-Tag: v1.7.7.1~21^2 X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=8cb5775b2b9885708c3f646a1e273de1ac778a88;p=git.git grep: Fix race condition in delta_base_cache When running large git grep (ie: git grep regexp $(git rev-list --all)), glibc error sometimes occur: *** glibc detected *** git: double free or corruption (!prev): 0x00000000010abdf0 *** According to gdb the problem originate from release_delta_cash (sha1_file.c:1703) free(ent->data); >From my analysis it seems that git grep threads do acquire lock before calling read_sha1_file but not before calling read_object_with_reference who ends up calling read_sha1_file too. Adding the lock around read_object_with_reference seems to fix the issue for me. I've ran git grep about a dozen time and seen no more error while it usually happened half the time before. Signed-off-by: Nicolas Morey-Chaisemartin Signed-off-by: Junio C Hamano --- diff --git a/builtin-grep.c b/builtin-grep.c index 6cc743d7c..0eb192d48 100644 --- a/builtin-grep.c +++ b/builtin-grep.c @@ -632,8 +632,12 @@ static int grep_object(struct grep_opt *opt, const char **paths, void *data; unsigned long size; int hit; + + read_sha1_lock(); data = read_object_with_reference(obj->sha1, tree_type, &size, NULL); + read_sha1_unlock(); + if (!data) die("unable to read tree (%s)", sha1_to_hex(obj->sha1)); init_tree_desc(&tree, data, size);