about summary refs log tree commit diff
path: root/libio
diff options
context:
space:
mode:
authorFlorian Weimer <fweimer@redhat.com>2024-01-02 14:36:17 +0100
committerFlorian Weimer <fweimer@redhat.com>2024-01-02 14:36:17 +0100
commitecc7c3deb9f347649c2078fcc0f94d4cedf92d60 (patch)
treeabe55d643161698f999e9c95e0fbec43d140ce44 /libio
parent5eabdb6a6ac1599d23dd5966a37417215950245f (diff)
downloadglibc-ecc7c3deb9f347649c2078fcc0f94d4cedf92d60.tar.gz
glibc-ecc7c3deb9f347649c2078fcc0f94d4cedf92d60.tar.xz
glibc-ecc7c3deb9f347649c2078fcc0f94d4cedf92d60.zip
libio: Check remaining buffer size in _IO_wdo_write (bug 31183)
The multibyte character needs to fit into the remaining buffer space,
not the already-written buffer space.  Without the fix, we were never
moving the write pointer from the start of the buffer, always using
the single-character fallback buffer.

Fixes commit 04b76b5aa8b2d1d19066e42dd1 ("Don't error out writing
a multibyte character to an unbuffered stream (bug 17522)").
Diffstat (limited to 'libio')
-rw-r--r--libio/wfileops.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/libio/wfileops.c b/libio/wfileops.c
index 17384296e6..6de5968358 100644
--- a/libio/wfileops.c
+++ b/libio/wfileops.c
@@ -55,7 +55,7 @@ _IO_wdo_write (FILE *fp, const wchar_t *data, size_t to_do)
 	  char mb_buf[MB_LEN_MAX];
 	  char *write_base, *write_ptr, *buf_end;
 
-	  if (fp->_IO_write_ptr - fp->_IO_write_base < sizeof (mb_buf))
+	  if (fp->_IO_buf_end - fp->_IO_write_ptr < sizeof (mb_buf))
 	    {
 	      /* Make sure we have room for at least one multibyte
 		 character.  */