Commit 09368960 authored Sep 24, 2014 by Vladimir Zapolskiy Committed by Greg Kroah-Hartman Nov 07, 2014

fs: sysfs: return EGBIG on write if offset is larger than file size



According to the user expectations common utilities like dd or sh
redirection operator > should work correctly over binary files from
sysfs. At the moment doing excessive write can not be completed:

  write(1, "\0\0\0\0\0\0\0\0", 8)         = 4
  write(1, "\0\0\0\0", 4)                 = 0
  write(1, "\0\0\0\0", 4)                 = 0
  write(1, "\0\0\0\0", 4)                 = 0
  ...

Fix the problem by returning EFBIG described in man 2 write.

Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 41fb96a4

fs/sysfs/file.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -125,7 +125,7 @@ static ssize_t sysfs_kf_bin_write(struct kernfs_open_file of, char buf,

	if (size) {		if (size) {
	if (size <= pos)		if (size <= pos)
	return 0;		return -EFBIG;
	count = min_t(ssize_t, count, size - pos);		count = min_t(ssize_t, count, size - pos);
	}		}
	if (!count)		if (!count)