From 94a0171d807dc94302d6505041fc58879c27f3bd Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Sat, 16 Jul 2011 21:24:02 -0400 Subject: [PATCH 1/1] fix logic error in fread fread was calling f->read without checking that the file was in reading mode. this could: 1. crash, if f->read was a null pointer 2. cause unwanted blocking on a terminal already at eof 3. allow reading on a write-only file --- src/stdio/fread.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/src/stdio/fread.c b/src/stdio/fread.c index 8105fe99..5c235777 100644 --- a/src/stdio/fread.c +++ b/src/stdio/fread.c @@ -21,14 +21,9 @@ size_t fread(void *destv, size_t size, size_t nmemb, FILE *f) l -= k; } - if (!l) { - FUNLOCK(f); - return nmemb; - } - /* Read the remainder directly */ for (; l; l-=k, dest+=k) { - k = f->read(f, dest, l); + k = __toread(f) ? 0 : f->read(f, dest, l); if (k+1<=1) { FUNLOCK(f); return (len-l)/size; -- 2.20.1