Remove suid/sgid bits on [f]truncate()



.. to match what we do on write().  This way, people who write to files
by using [f]truncate + writable mmap have the same semantics as if they
were using the write() family of system calls.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 1efd48b3

fs/open.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -210,6 +210,9 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
		newattrs.ia_valid \|= ATTR_FILE;
		}

		/* Remove suid/sgid on truncate too */
		newattrs.ia_valid \|= should_remove_suid(dentry);

		mutex_lock(&dentry->d_inode->i_mutex);
		err = notify_change(dentry, &newattrs);
		mutex_unlock(&dentry->d_inode->i_mutex);