From 3f419d45ef0dfc33dc301d9ae4737043c091291a Mon Sep 17 00:00:00 2001
From: Jeff King <peff@peff.net>
Date: Fri, 7 Mar 2014 12:15:01 -0500
Subject: [PATCH] show_ident_date: fix tz range check
Commit 1dca155fe3fa (log: handle integer overflow in
timestamps, 2014-02-24) tried to catch integer overflow
coming from strtol() on the timezone field by comparing against
LONG_MIN/LONG_MAX. However, the intermediate "tz" variable
is an "int", which means it can never be LONG_MAX on LP64
systems; we would truncate the output from strtol before the
comparison.
Clang's -Wtautological-constant-out-of-range-compare notices
this and rightly complains.
Let's instead store the result of strtol in a long, and then
compare it against INT_MIN/INT_MAX. This will catch overflow
from strtol, and also overflow when we pass the result as an
int to show_date.
Reported-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
pretty.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/pretty.c b/pretty.c
index 4da9a682f3b..4d4c1e95625 100644
--- a/pretty.c
+++ b/pretty.c
@@ -397,7 +397,7 @@ static const char *show_ident_date(const struct ident_split *ident,
enum date_mode mode)
{
unsigned long date = 0;
- int tz = 0;
+ long tz = 0;
if (ident->date_begin && ident->date_end)
date = strtoul(ident->date_begin, NULL, 10);
@@ -406,7 +406,7 @@ static const char *show_ident_date(const struct ident_split *ident,
else {
if (ident->tz_begin && ident->tz_end)
tz = strtol(ident->tz_begin, NULL, 10);
- if (tz == LONG_MAX || tz == LONG_MIN)
+ if (tz >= INT_MAX || tz <= INT_MIN)
tz = 0;
}
return show_date(date, tz, mode);