From 3fe37e36faa6c76dd0e4b5051a9a59ec6a0bc140 Mon Sep 17 00:00:00 2001
From: David Carlier <devnexen@gmail.com>
Date: Sun, 26 Mar 2023 08:33:30 +0100
Subject: [PATCH] reallocarray introduction available on glibc 2.26. allocates
an array of m*n elements but checking for overflow.
---
src/header/stdlib/mod.rs | 16 ++++++++++++++++
tests/expected/bins_static/stdlib/alloc.stdout | 2 ++
tests/stdlib/alloc.c | 16 ++++++++++++++++
3 files changed, 34 insertions(+)
diff --git a/src/header/stdlib/mod.rs b/src/header/stdlib/mod.rs
index ee39ae05..59d6de50 100644
--- a/src/header/stdlib/mod.rs
+++ b/src/header/stdlib/mod.rs
@@ -812,6 +812,22 @@ pub unsafe extern "C" fn realloc(ptr: *mut c_void, size: size_t) -> *mut c_void
new_ptr
}
+#[no_mangle]
+pub unsafe extern "C" fn reallocarray(ptr: *mut c_void, m: size_t, n: size_t) -> *mut c_void {
+ //Handle possible integer overflow in size calculation
+ match m.checked_mul(n) {
+ Some(size) => {
+ realloc(ptr, size)
+ }
+ None => {
+ // For overflowing multiplication, we have to set errno here
+ platform::errno = ENOMEM;
+ ptr::null_mut()
+
+ }
+ }
+}
+
#[no_mangle]
pub unsafe extern "C" fn realpath(pathname: *const c_char, resolved: *mut c_char) -> *mut c_char {
let ptr = if resolved.is_null() {
diff --git a/tests/expected/bins_static/stdlib/alloc.stdout b/tests/expected/bins_static/stdlib/alloc.stdout
index e59a48d0..02ecd201 100644
--- a/tests/expected/bins_static/stdlib/alloc.stdout
+++ b/tests/expected/bins_static/stdlib/alloc.stdout
@@ -7,6 +7,8 @@ calloc (overflowing): pointer: (nil), error value: 12 = Out of memory
realloc (size 0): (OK)
realloc: pointer: (not NULL), error value: 0 = Success
realloc (SIZE_MAX): pointer: (nil), error value: 12 = Out of memory
+reallocarray: pointer: (not NULL), error value: 0 = Success
+reallocarray (SIZE_MAX): pointer: (nil), error value: 12 = Out of memory
memalign (size 0): (OK)
memalign: pointer: (alignment OK), error value: 0 = Success
memalign (SIZE_MAX): pointer: (nil), error value: 12 = Out of memory
diff --git a/tests/stdlib/alloc.c b/tests/stdlib/alloc.c
index 36660363..f15149b5 100644
--- a/tests/stdlib/alloc.c
+++ b/tests/stdlib/alloc.c
@@ -165,6 +165,22 @@ int main(void) {
printf("realloc (SIZE_MAX): ");
test_cannot_alloc(ptr_realloc_maxsize, realloc_maxsize_errno);
free(ptr_realloc_maxsize);
+
+ errno = 0;
+ char * ptr_reallocarray_maxsize = (char *)malloc(sample_alloc_size);
+ ptr_reallocarray_maxsize = (char *)reallocarray(ptr_reallocarray_maxsize, 2, sample_alloc_size);
+ int reallocarray_errno = errno;
+ printf("reallocarray: ");
+ test_non_null(ptr_reallocarray_maxsize, reallocarray_errno);
+ for(i = 0; i < sample_realloc_size; i++) {
+ ptr_realloc[i] = (char)i;
+ }
+ errno = 0;
+ ptr_reallocarray_maxsize = (char *)reallocarray(ptr_reallocarray_maxsize, 2, max_size);
+ reallocarray_errno = errno;
+ printf("reallocarray (SIZE_MAX): ");
+ test_cannot_alloc(ptr_reallocarray_maxsize, reallocarray_errno);
+ free(ptr_reallocarray_maxsize);
errno = 0;
char * ptr_memalign_size0 = (char *)memalign(aligned_alloc_alignment, zero_size);
--
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