From 1ebd8a3d723291e7f120b3c95b2e5141c9ef93b3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mateusz=20Miku=C5=82a?= <matti@marinelayer.io>
Date: Wed, 24 Apr 2019 17:32:06 +0200
Subject: [PATCH] Handle zero length for strerror_r
---
src/header/string/mod.rs | 6 ++++--
tests/error.c | 4 ++++
tests/expected/error.stdout | 1 +
3 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/src/header/string/mod.rs b/src/header/string/mod.rs
index 8c8acb216..c402707f3 100644
--- a/src/header/string/mod.rs
+++ b/src/header/string/mod.rs
@@ -235,8 +235,10 @@ pub unsafe extern "C" fn strerror_r(errnum: c_int, buf: *mut c_char, buflen: siz
let len = strlen(msg);
if len >= buflen {
- memcpy(buf as *mut c_void, msg as *const c_void, buflen - 1);
- *buf.add(buflen - 1) = 0;
+ if buflen != 0 {
+ memcpy(buf as *mut c_void, msg as *const c_void, buflen - 1);
+ *buf.add(buflen - 1) = 0;
+ }
return ERANGE as c_int;
}
memcpy(buf as *mut c_void, msg as *const c_void, len + 1);
diff --git a/tests/error.c b/tests/error.c
index bb613b922..5cbe10385 100644
--- a/tests/error.c
+++ b/tests/error.c
@@ -19,4 +19,8 @@ int main(void) {
char buf2[3];
int ret2 = strerror_r(err, buf2, 3);
printf("errno: %d = %s, return: %d\n", err, buf2, ret2);
+
+ char buf3[256];
+ int ret3 = strerror_r(err, buf3, 0);
+ printf("errno: %d = %s, return: %d\n", err, buf3, ret3);
}
diff --git a/tests/expected/error.stdout b/tests/expected/error.stdout
index d1c1a211f..4e744d1bf 100644
--- a/tests/expected/error.stdout
+++ b/tests/expected/error.stdout
@@ -1,3 +1,4 @@
errno: 2 = No such file or directory
errno: 2 = No such file or directory, return: 0
errno: 2 = No, return: 34
+errno: 2 = , return: 34
--
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