TOMOYO: Fix infinite loop bug when reading /sys/kernel/security/tomoyo/audit

In tomoyo_flush(), head->r.w[0] holds pointer to string data to be printed.
But head->r.w[0] was updated only when the string data was partially
printed (because head->r.w[0] will be updated by head->r.w[1] later if
completely printed). However, regarding /sys/kernel/security/tomoyo/query ,
an additional '\0' is printed after the string data was completely printed.
But if free space for read buffer became 0 before printing the additional '\0',
tomoyo_flush() was returning without updating head->r.w[0]. As a result,
tomoyo_flush() forever reprints already printed string data.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
Tetsuo Handa 2011-04-03 00:12:54 +09:00 committed by James Morris
parent e4f5f26d83
commit c0fa797ae6

View File

@ -108,10 +108,9 @@ static bool tomoyo_flush(struct tomoyo_io_buffer *head)
head->read_user_buf += len;
w += len;
}
if (*w) {
head->r.w[0] = w;
head->r.w[0] = w;
if (*w)
return false;
}
/* Add '\0' for query. */
if (head->poll) {
if (!head->read_user_buf_avail ||