Re: [PATCH 1/2] read_and_strip_branch: fix typo'd address-of operator
From: Junio C Hamano <hidden>
Date: 2016-06-15 23:03:41
Jeff King [off-list ref] writes:
When we are chomping newlines from the end of a strbuf, we must check "sb.len != 0" before accessing "sb.buf[sb.len - 1]". However, this code mistakenly checks "&sb.len", which is always true (it is a part of an auto struct, so the address is always non-zero). This could lead to us accessing memory outside the strbuf when we read an empty file. Signed-off-by: Jeff King <redacted> --- This dates back to 8b87cfd (wt-status: move strbuf into read_and_strip_branch(), 2013-03-16), so it is not a bug that needs addressed during the -rc period. This is the most minimal fix, but I kind of wonder if it should just be using strbuf_rtrim (or even strbuf_trim) in the first place.
Yeah. Or strbuf_chomp(), which does not exist ;-) It is tempting to apply this directly to maint and merge up immediately, as there is no way this 1-byte change will break things (of course that is not necessarily true for random 1-byte changes, though). It sometimes gets really hard to resist that temptation during the pre-release freeze period.
quoted hunk
wt-status.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/wt-status.c b/wt-status.c index b54eac5..29666d0 100644 --- a/wt-status.c +++ b/wt-status.c@@ -1140,7 +1140,7 @@ static char *read_and_strip_branch(const char *path) if (strbuf_read_file(&sb, git_path("%s", path), 0) <= 0) goto got_nothing; - while (&sb.len && sb.buf[sb.len - 1] == '\n') + while (sb.len && sb.buf[sb.len - 1] == '\n') strbuf_setlen(&sb, sb.len - 1); if (!sb.len) goto got_nothing;