From b69c124255e25d5d1c16ee88c4f2a75964db9209 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= Date: Thu, 4 Jan 2018 11:34:05 +0200 Subject: [PATCH] Fix potential overflow in TrustedRandomAccess impl for slice::{Chunks,ChunksMut} --- src/libcore/slice/mod.rs | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/src/libcore/slice/mod.rs b/src/libcore/slice/mod.rs index 9b8334167f55..72036d6d3a24 100644 --- a/src/libcore/slice/mod.rs +++ b/src/libcore/slice/mod.rs @@ -2240,7 +2240,10 @@ impl<'a, T> FusedIterator for Chunks<'a, T> {} unsafe impl<'a, T> TrustedRandomAccess for Chunks<'a, T> { unsafe fn get_unchecked(&mut self, i: usize) -> &'a [T] { let start = i * self.chunk_size; - let end = cmp::min(start + self.chunk_size, self.v.len()); + let end = match start.checked_add(self.chunk_size) { + None => self.v.len(), + Some(end) => cmp::min(end, self.v.len()), + }; from_raw_parts(self.v.as_ptr().offset(start as isize), end - start) } fn may_have_side_effect() -> bool { false } @@ -2353,7 +2356,10 @@ impl<'a, T> FusedIterator for ChunksMut<'a, T> {} unsafe impl<'a, T> TrustedRandomAccess for ChunksMut<'a, T> { unsafe fn get_unchecked(&mut self, i: usize) -> &'a mut [T] { let start = i * self.chunk_size; - let end = cmp::min(start + self.chunk_size, self.v.len()); + let end = match start.checked_add(self.chunk_size) { + None => self.v.len(), + Some(end) => cmp::min(end, self.v.len()), + }; from_raw_parts_mut(self.v.as_mut_ptr().offset(start as isize), end - start) } fn may_have_side_effect() -> bool { false }