commit 705a79f82560ff6472cebed86aa5db04cdea3bce

Author: Florian Weimer <fweimer@redhat.com>

Date:   Wed Nov 30 14:59:27 2016 +0100

    libio: Limit buffer size to 8192 bytes [BZ #4099]

    This avoids overly large buffers with network file systems which report

    very large block sizes.

Index: b/libio/filedoalloc.c

===================================================================

--- a/libio/filedoalloc.c

+++ b/libio/filedoalloc.c

@@ -121,7 +121,7 @@ _IO_file_doallocate (fp)

 	    fp->_flags |= _IO_LINE_BUF;

 	}

 #if _IO_HAVE_ST_BLKSIZE

-      if (st.st_blksize > 0)

+      if (st.st_blksize > 0 && st.st_blksize < _IO_BUFSIZ)

 	size = st.st_blksize;

 #endif

     }