From 8dd55d9ee107337460e6a35b4ece234b4475e12d Mon Sep 17 00:00:00 2001 From: Richard Levitte Date: Fri, 4 May 2018 14:44:19 +0200 Subject: [PATCH] BIO_s_mem() write: Skip early when input length is zero When the input length is zero, just return zero early. Otherwise, there's a small chance that memory allocation is engaged, fails and returns -1, which is a bit confusing when nothing should be written. Fixes #4782 #4827 Reviewed-by: Ben Kaduk (Merged from https://github.com/openssl/openssl/pull/6175) (cherry picked from commit 0d94212a046e87fafea6e83e8ea2b2a58db49979) --- crypto/bio/bss_mem.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/crypto/bio/bss_mem.c b/crypto/bio/bss_mem.c index b0394a960d..6ccb8e2788 100644 --- a/crypto/bio/bss_mem.c +++ b/crypto/bio/bss_mem.c @@ -188,6 +188,8 @@ static int mem_write(BIO *b, const char *in, int inl) } BIO_clear_retry_flags(b); + if (inl == 0) + return 0; blen = bm->length; if (BUF_MEM_grow_clean(bm, blen + inl) != (blen + inl)) goto end; -- 2.25.1