Commit f7b88631 authored Jul 19, 2011 by Akinobu Mita Committed by Linus Torvalds Jul 19, 2011

fs/libfs.c: fix simple_attr_write() on 32bit machines



Assume that /sys/kernel/debug/dummy64 is debugfs file created by
debugfs_create_x64().

	# cd /sys/kernel/debug
	# echo 0x1234567812345678 > dummy64
	# cat dummy64
	0x0000000012345678

	# echo 0x80000000 > dummy64
	# cat dummy64
	0xffffffff80000000

A value larger than INT_MAX cannot be written to the debugfs file created
by debugfs_create_u64 or debugfs_create_x64 on 32bit machine.  Because
simple_attr_write() uses simple_strtol() for the conversion.

To fix this, use simple_strtoll() instead.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent e501f29c

fs/libfs.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -822,7 +822,7 @@ ssize_t simple_attr_write(struct file file, const char __user buf,
		goto out;

		attr->set_buf[size] = '\0';
		val = simple_strtol(attr->set_buf, NULL, 0);
		val = simple_strtoll(attr->set_buf, NULL, 0);
		ret = attr->set(attr->data, val);
		if (ret == 0)
		ret = len; /* on success, claim we got the whole input */

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