From 70e14ffbaf6a67dab56c24cae01f1248cf3f1e77 Mon Sep 17 00:00:00 2001 From: Pauli Date: Fri, 17 Feb 2017 10:39:20 +1000 Subject: [PATCH] Ensure minsize >= sizeof(SH_LIST) The sh_add_to_list function will overwrite subsequent slots in the free list for small allocations. This causes a segmentation fault if the writes goes off the end of the secure memory. I've not investigated if this problem can overwrite memory without the segmentation fault, but it seems likely. This fix limits the minsize to the sizeof of the SH_LIST structure (which also has a side effect of properly aligning the pointers). The alternative would be to return an error if minsize is too small. Reviewed-by: Richard Levitte Reviewed-by: Rich Salz (Merged from https://github.com/openssl/openssl/pull/2657) --- crypto/mem_sec.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/crypto/mem_sec.c b/crypto/mem_sec.c index 0c79b43658..4a3f2a84a2 100644 --- a/crypto/mem_sec.c +++ b/crypto/mem_sec.c @@ -1,5 +1,5 @@ /* - * Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved. + * Copyright 2015-2017 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the OpenSSL license (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy @@ -352,6 +352,9 @@ static int sh_init(size_t size, int minsize) if (minsize <= 0 || (minsize & (minsize - 1)) != 0) goto err; + while (minsize < (int)sizeof(SH_LIST)) + minsize *= 2; + sh.arena_size = size; sh.minsize = minsize; sh.bittable_size = (sh.arena_size / sh.minsize) * 2; -- 2.25.1