pstore: Convert console write to use ->write_buf

Maybe I'm missing something, but I don't know why it needs to copy the
input buffer to psinfo->buf and then write.  Instead we can write the
input buffer directly.  The only implementation that supports console
message (i.e. ramoops) already does it for ftrace messages.

For the upcoming virtio backend driver, it needs to protect psinfo->buf
overwritten from console messages.  If it could use ->write_buf method
instead of ->write, the problem will be solved easily.

Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
This commit is contained in:
Namhyung Kim 2016-10-19 10:23:41 +09:00 committed by Kees Cook
parent e9e360b08a
commit 70ad35db33
1 changed files with 2 additions and 2 deletions

View File

@ -585,8 +585,8 @@ static void pstore_console_write(struct console *con, const char *s, unsigned c)
} else {
spin_lock_irqsave(&psinfo->buf_lock, flags);
}
memcpy(psinfo->buf, s, c);
psinfo->write(PSTORE_TYPE_CONSOLE, 0, &id, 0, 0, 0, c, psinfo);
psinfo->write_buf(PSTORE_TYPE_CONSOLE, 0, &id, 0,
s, 0, c, psinfo);
spin_unlock_irqrestore(&psinfo->buf_lock, flags);
s += c;
c = e - s;