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 756FD202991; Fri, 4 Apr 2025 00:06:47 +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=1743725207; cv=none; b=R/Sksxj8EWqd/fzDbmmHdBTGuUEHEeN7+KDeLF+RRME5TxZYCsjSZc02OjsMAuM08ZjLblig6MDq58anCMleMVpBjHKhuwhk/Vd91JDSyq+wrIuNORFXkiAYmRzsqvLJIFqSe9lw8elWZn9uysYJSSr3SsndwfymTbFo07YZE1c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743725207; c=relaxed/simple; bh=mk+yGaMYbXEcpKulZAEG/o59etxEz+0+S7aN3CTTJd8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Pe8zHJs7CuGKOAMeMogXx5xaZff3R9u+F3tPL6C2PTl4ZgB9g8ScqZAtWrbvDRsP98NxvPK4MzcUMlnZ6Ob0B8lSy8sFNMqARSBCuZlmh5m9C2R0DxEQtSbP9oOzOJrjTBbqIHfzp2FtwLHtI0p/xjwnsRYNCTMZPF1gsuasluA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OlAG90Ih; 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="OlAG90Ih" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7744BC4CEE3; Fri, 4 Apr 2025 00:06:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743725207; bh=mk+yGaMYbXEcpKulZAEG/o59etxEz+0+S7aN3CTTJd8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OlAG90IhTo33m2fxgDajVQnl+18iqUKcYfUPK+yxa+8gV9hBLQ1h63mqOynlYYjMV S3W9q+yb23y1cZaY1i1tiiBDW4ijYCwllpIwqrYS8x9jEPFk2rVe34GHimtdZRH7rK zcCXIR2EIe5PxlD+CgGlajV9kzKv1eyaGK9zk4DHUwpHR3qWyfu5MOa8DVHYbiEU5T r8WlGk0CZBydNHH6gWnR9hkJkbzi9QF5yLoCwrYZkztkbjSo6b182kq5WzjAEcC5QT NuwkqJ1KQTfrLiG0p1u5iwKp6707oMSRU58cAsWANLO44pAsmA36xr9y0OOxWPO7hs Vx52fcxLYIIAA== 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 6.6 09/16] s390/sclp: Add check for get_zeroed_page() Date: Thu, 3 Apr 2025 20:06:17 -0400 Message-Id: <20250404000624.2688940-9-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250404000624.2688940-1-sashal@kernel.org> References: <20250404000624.2688940-1-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 6.6.85 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 e5d947c763ea5..6a030ba38bf36 100644 --- a/drivers/s390/char/sclp_con.c +++ b/drivers/s390/char/sclp_con.c @@ -263,6 +263,19 @@ 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. */ @@ -282,6 +295,10 @@ 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