From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0C30620967A; Fri, 4 Apr 2025 00:07:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743725265; cv=none; b=MZ+6v4ElO0ISj9eFuIXGRTu+6uszluJO+TWmRxfCfYT0L0nbaRPPElwZ7Otf6YiiSip1AhvBGELidrkNbzOHDKSk+K0W5xVjkAtRSWrQzxeAf7Ao8RZWTojO1V+kN7qs+h/JL/AihfVuYVJeHW+kHYQTHiCzJuh9YCXeOXQBr7U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743725265; c=relaxed/simple; bh=0R6JZFKvBVwUWDQOVvhGUO8V6OZzqEomBf5wQswfFd8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Qh61BfBhLyJV0zUcIJARqpR/C3QgSGvWMjGI1SMb4OIUw5z878vSHXyQ2b7XLeakfoOVi/UkVFyXEunYD7nUeUz6MlD0czH5Krv7pu1hXDQ043/MJNW8U8wDeBUsk641XtcZnJ60dusswrYT0H+TNTVftd4n34CNAhL4tA0DtpU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ac7MTYW0; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ac7MTYW0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0BCBC4CEE5; Fri, 4 Apr 2025 00:07:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743725264; bh=0R6JZFKvBVwUWDQOVvhGUO8V6OZzqEomBf5wQswfFd8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ac7MTYW04lee3sR+B9KCt4TmUlKRstxO3840r593YD+HKQzGpuazrIDl4hy/nilSO 0DMWJNW7EvuAXlfNSqfh8IooXXB4tts0W7T8svW9wCSvLQzK1Ga/8TgNtdBfpyB2hx vFzytPfGJ0uJlcsgevDdbmj129zkg3Dw2XOu8oxEivJeWm2Vu3TPAgiduDtM2BxDny MejbOzd6aq2lpMcwsEpfi6kChAhg2U6zWTXZPPayl7cia4+NThGI6aay4ERy7quJiR L9yrH7PawT8pLEgParpf8nWFJcVlHBEz8E+UeNwUI4QGNTtUh5d2+5RMMAQPevoobI UqITJeL+1oHlQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Haoxiang Li , Heiko Carstens , Vasily Gorbik , Sasha Levin , agordeev@linux.ibm.com, linux-s390@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 6/8] s390/sclp: Add check for get_zeroed_page() Date: Thu, 3 Apr 2025 20:07:24 -0400 Message-Id: <20250404000728.2689305-6-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250404000728.2689305-1-sashal@kernel.org> References: <20250404000728.2689305-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.15.179 Content-Transfer-Encoding: 8bit From: Haoxiang Li [ Upstream commit 3db42c75a921854a99db0a2775814fef97415bac ] Add check for the return value of get_zeroed_page() in sclp_console_init() to prevent null pointer dereference. Furthermore, to solve the memory leak caused by the loop allocation, add a free helper to do the free job. Signed-off-by: Haoxiang Li Acked-by: Heiko Carstens Link: https://lore.kernel.org/r/20250218025216.2421548-1-haoxiang_li2024@163.com Signed-off-by: Vasily Gorbik Signed-off-by: Sasha Levin --- drivers/s390/char/sclp_con.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/s390/char/sclp_con.c b/drivers/s390/char/sclp_con.c index de028868c6f4a..4e5d5da258d68 100644 --- a/drivers/s390/char/sclp_con.c +++ b/drivers/s390/char/sclp_con.c @@ -260,6 +260,19 @@ static struct console sclp_console = .index = 0 /* ttyS0 */ }; +/* + * Release allocated pages. + */ +static void __init __sclp_console_free_pages(void) +{ + struct list_head *page, *p; + + list_for_each_safe(page, p, &sclp_con_pages) { + list_del(page); + free_page((unsigned long)page); + } +} + /* * called by console_init() in drivers/char/tty_io.c at boot-time. */ @@ -279,6 +292,10 @@ sclp_console_init(void) /* Allocate pages for output buffering */ for (i = 0; i < sclp_console_pages; i++) { page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA); + if (!page) { + __sclp_console_free_pages(); + return -ENOMEM; + } list_add_tail(page, &sclp_con_pages); } sclp_conbuf = NULL; -- 2.39.5