fs/libfs.c: fix simple_attr_write() on 32bit machines
authorAkinobu Mita <akinobu.mita@gmail.com>
Tue, 19 Jul 2011 15:49:25 +0000 (08:49 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 20 Jul 2011 05:09:30 +0000 (22:09 -0700)
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>
fs/libfs.c

index c88eab55aec95f4ab26427da882fd88c8b3ef512..275ca4749a2ee3280fd0544680c1df4f23baf3d5 100644 (file)
@@ -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 */