From 5c35dc008c6bf990f18226c4a1a455ec98d4cc43 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 43033a3d66d5..2434bffbc6dd 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -584,8 +584,8 @@ 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;