From 7f0324fb34c4736bf12ae8a5137e6913772749cc Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Wed, 19 Oct 2016 10:23:41 +0900 Subject: [PATCH] pstore: Convert console write to use ->write_buf [ Upstream commit 70ad35db3321a6d129245979de4ac9d06eed897c ] 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 Signed-off-by: Namhyung Kim Signed-off-by: Kees Cook Signed-off-by: Sasha Levin --- fs/pstore/platform.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index 588461bb2dd4..e97e7d74e134 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -392,8 +392,8 @@ 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;