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 6AFDF381D4; Fri, 24 Nov 2023 18:28:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="I2uEiFKX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EC2F2C433C7; Fri, 24 Nov 2023 18:28:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1700850490; bh=B/mtAHzwvr32IBqCIQePECIbKP/uz8c/4BGPiiX7rxU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=I2uEiFKXNVJD+Bq7HfCib4nhg7R6ounA0oNYQFkn65ZD8Qq2bFkCwAt2rrI9MmfVa h5GpsWEOwT38DoQMqrkLMWERDARqEEhvSNuqEQJnOtLYsVuY11rfnUpQvdCT5GoN6L oYkKOil6PUAhNja8CzVfdkwOyeHpA/obAM/Mdr1c= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yu Kuai , Song Liu , Sasha Levin Subject: [PATCH 6.5 052/491] md: dont rely on mddev->pers to be set in mddev_suspend() Date: Fri, 24 Nov 2023 17:44:48 +0000 Message-ID: <20231124172026.245973419@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231124172024.664207345@linuxfoundation.org> References: <20231124172024.664207345@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yu Kuai [ Upstream commit b721e7885eb242aa2459ee66bb42ceef1bcf0f0c ] 'active_io' used to be initialized while the array is running, and 'mddev->pers' is set while the array is running as well. Hence caller must hold 'reconfig_mutex' and guarantee 'mddev->pers' is set before calling mddev_suspend(). Now that 'active_io' is initialized when mddev is allocated, such restriction doesn't exist anymore. In the meantime, follow up patches will refactor mddev_suspend(), hence add checking for 'mddev->pers' to prevent null-ptr-deref. Signed-off-by: Yu Kuai Signed-off-by: Song Liu Link: https://lore.kernel.org/r/20230825030956.1527023-4-yukuai1@huaweicloud.com Signed-off-by: Sasha Levin --- drivers/md/md.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 78d51dddf3a00..34b7196d9634c 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -449,7 +449,7 @@ void mddev_suspend(struct mddev *mddev) set_bit(MD_ALLOW_SB_UPDATE, &mddev->flags); percpu_ref_kill(&mddev->active_io); - if (mddev->pers->prepare_suspend) + if (mddev->pers && mddev->pers->prepare_suspend) mddev->pers->prepare_suspend(mddev); wait_event(mddev->sb_wait, percpu_ref_is_zero(&mddev->active_io)); -- 2.42.0