From 36c831972497c1141a704fb5ad179675111ee321 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Thu, 11 Apr 2019 09:49:25 -0400 Subject: [PATCH] xdiff: use xmalloc/xrealloc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Most of xdiff uses a bare malloc() to allocate memory, and returns an error when we get NULL. However, there are a few spots which don't check the return value and may segfault, including at least xdl_merge() and xpatience.c's find_longest_common_sequence(). Let's use xmalloc() everywhere instead, so that we get a graceful die() for these cases, without having to do further auditing. This does mean the existing cases which check errors will now die() instead of returning an error up the stack. But: - that's how the rest of Git behaves already for malloc errors - all of the callers of xdi_diff(), etc, die upon seeing an error So while we might one day want to fully lib-ify the diff code and make it possible to use as part of a long-running process, we're not close to that now. And because we're just tweaking the xdl_malloc() macro here, we're not really moving ourselves any further away from that. We could, for example, simplify some of the functions which handle malloc() errors which can no longer occur. But that would probably be taking us in the wrong direction. This also makes our malloc handling more consistent with the rest of Git, including enforcing GIT_ALLOC_LIMIT and trying to reclaim pack memory when needed. Reported-by: 王健强 Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- xdiff/xdiff.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/xdiff/xdiff.h b/xdiff/xdiff.h index b1583690208096..032e3a9f41a2f7 100644 --- a/xdiff/xdiff.h +++ b/xdiff/xdiff.h @@ -113,9 +113,9 @@ typedef struct s_bdiffparam { } bdiffparam_t; -#define xdl_malloc(x) malloc(x) +#define xdl_malloc(x) xmalloc(x) #define xdl_free(ptr) free(ptr) -#define xdl_realloc(ptr,x) realloc(ptr,x) +#define xdl_realloc(ptr,x) xrealloc(ptr,x) void *xdl_mmfile_first(mmfile_t *mmf, long *size); long xdl_mmfile_size(mmfile_t *mmf);