# [PATCH] dir.c: clean the entire struct in clear_exclude_list() 2 messages from 2015-12-27 to 2015-12-28. Participants: Nguyễn Thái Ngọc Duy, Junio C Hamano. Thread: https://gitlist.dev/t/41080 ## Nguyễn Thái Ngọc Duy, 2015-12-27 01:54 Subject: [PATCH] dir.c: clean the entire struct in clear_exclude_list() Message-ID: <1451181274-26213-1-git-send-email-pclouds@gmail.com> URL: https://gitlist.dev/e/1451181274-26213-1-git-send-email-pclouds%40gmail.com ``` Make sure "el" can be reuseable again. The problem was el->alloc is not cleared and may cause segfaults next time because add_exclude() thinks el->excludes (being NULL) has enough space. Just clear the entire struct to be safe. Signed-off-by: Nguyễn Thái Ngọc Duy --- This was needed in the worktree config split series because the same exclude_list could be reused. But that series is changing and will not need exclude_list any more. So instead of dropping this patch, I submit it separately. It's a good fix anyway. dir.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/dir.c b/dir.c index d2a8f06..b8b4576 100644 --- a/dir.c +++ b/dir.c @@ -564,9 +564,7 @@ void clear_exclude_list(struct exclude_list *el) free(el->excludes); free(el->filebuf); - el->nr = 0; - el->excludes = NULL; - el->filebuf = NULL; + memset(el, 0, sizeof(*el)); } static void trim_trailing_spaces(char *buf) -- 2.3.0.rc1.137.g477eb31 ``` ## Junio C Hamano, 2015-12-28 20:47 Subject: Re: [PATCH] dir.c: clean the entire struct in clear_exclude_list() Message-ID: URL: https://gitlist.dev/e/xmqqtwn2jo5d.fsf%40gitster.mtv.corp.google.com In-Reply-To: <1451181274-26213-1-git-send-email-pclouds@gmail.com> ``` Nguyễn Thái Ngọc Duy writes: > Make sure "el" can be reuseable again. The problem was el->alloc is > not cleared and may cause segfaults next time because add_exclude() > thinks el->excludes (being NULL) has enough space. Just clear the > entire struct to be safe. OK. If somebody ever adds a field to this structure that should not be cleared by filling it with '\0', that person would notice and turn this memset() back to individual field assignment, but until then, I think memset is a reasonable thing to do, as that is how it is initialized by add_exclude_list() in the first place anyway. Will apply. > Signed-off-by: Nguyễn Thái Ngọc Duy > --- > This was needed in the worktree config split series because the same > exclude_list could be reused. But that series is changing and will not > need exclude_list any more. So instead of dropping this patch, I > submit it separately. It's a good fix anyway. > > dir.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/dir.c b/dir.c > index d2a8f06..b8b4576 100644 > --- a/dir.c > +++ b/dir.c > @@ -564,9 +564,7 @@ void clear_exclude_list(struct exclude_list *el) > free(el->excludes); > free(el->filebuf); > > - el->nr = 0; > - el->excludes = NULL; > - el->filebuf = NULL; > + memset(el, 0, sizeof(*el)); > } > > static void trim_trailing_spaces(char *buf) ```