From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj2-f42.google.com (mail-pj2-f42.google.com [74.125.227.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 99371380FF4 for ; Tue, 22 Sep 2026 04:46:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.227.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790052377; cv=none; b=PgWMFUbZYi1yTCvwhmb76kdyINX+XIB7RJP6jVbG0MjQ8rWGG2ppIJF9dSXj3KmUJLIS7ujh8MeOXtdxQjlxyRvZlvow6vftZLbVKRZAa4GzNOfA2JbTdlb8LrmmaGZpi7dsj9F1YorGcOD4aPTb1p3GyubR++RbSVnQwXoOoOU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790052377; c=relaxed/simple; bh=LmqjBasxDWd9/DMzUXY/MJPkJcpcAJYfwEVP/qtHFmc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aKiiVccVgfc/hgc1G2bbNL2Yp0npFHWF0mP7dnnjamJL+niSUtz4JKQc51cwA0O+THDD2zsoRPcCsP40a0QR24+YKy/AKkj2pZh1H72Fkf8INjpKmf/n1Sna4mXl+fuqZYi2sLqiuUHrCYdXDmzkyfhs5lz6oddCuzPNoRqzmMo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=p6TKSxS+; arc=none smtp.client-ip=74.125.227.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="p6TKSxS+" Received: by mail-pj2-f42.google.com with SMTP id 98e67ed59e1d1-396ccda24afso2664211a91.3 for ; Mon, 21 Sep 2026 21:46:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1790052373; x=1790657173; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=3E+ocT2Bhu1iX7K4xkDhu5H7aG48frP1ov4mPcFNMD8=; b=p6TKSxS+3n5KXKvQNMuj1ceiHogZzRt+Ix9wwUuBtRE6VKdXLY1K07u6E3k8FtSd/p lfiSIe8ZE/Hvvc/rThv38IX4jMepEQwojMu5p1MG3d6dFrZ17/yNmGIVuLH4wVhEFjpr dr2Dn/JCKsBYl31lFQ8u5M2p8qb5++wn9pkynZs65WZ7I7TqeLHJ3FH7U6uY9pB0fORT GU0tPU8y3cbXzLEr8J9QuTiP+iw7CFObuGTBPPjGGvIlXU7plTGIsH6TBEvENXulG6ef s6RCyFO0+l386GOYfzh7dRpDIhjb2X7EOPXRKRC5yLSM50CG6cWj61ra7HXRKnuwZA/4 XySQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790052373; x=1790657173; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=3E+ocT2Bhu1iX7K4xkDhu5H7aG48frP1ov4mPcFNMD8=; b=PTu9Ezv+vMlSn7MAKnKQHmRRI5+9h0C7ozYjXoJE+6CQ1gx9Fpjm2F/fotAEmynizd To2huR5ldpydnnkMETMKL7/vIOim5LglmBtT8pxER8UO7rC0Z8mpreJz06amy6EbZ2nC EacgDzdCWzqIFdHedLVUdzdswDfesGZgPHFJsp7l0HtKAEkeV2tnWgNHkVWHHVCc963I mg1SpPBt9vRFcTVgStRbf3ckm6OKZd4n29ol5P4IQYtuKRz6ZDGeIxBK6GeyGfiWV5HL dN/xPOx4iT1Ihb1IVmZ4vMxi1gomjciAG4CSzfed131gGvbjkywUqlNBtTHsh+zv+z88 f4DA== X-Forwarded-Encrypted: i=1; AKwUvBzP902BnQmingLAkPvPNZahy8ODt7NttoZApp6TMmhJbCVukSvM+LMcXao/8S7UAzkHyLhWB7hhE0PY@vger.kernel.org X-Gm-Message-State: AFuF++kv2O4sOO+nsebBI8cnG5PjMY+V+isJjZ7o4sBNNw4cZD4FO5XL LVDy+92CRqjI086y+1Z9QDOHX2TFdh5BEXeL8sJ1/cIy9XrOcbfQkOss X-Gm-Gg: AYBFou3a3hNZOXky1DFNBJPh75+CB4lUpfU2WAziK7nkiEKnX7iHC5D6yHVji/ks43N kerhW91SvMyvD7lHDFJuFHKScHODDPEgjAe2EEOGsSrRDK+ifkGqURaBt5cWQZZv3hm/tUq27it eB3cRSGwC8fO1+0VUOZoahHRHxOUTO59Vj3J6Pq1Na1xSUOwtYvO676oxSZ7ITVrQOOfKSdg7OU qVC8ZyReR0HNAJxwazJZ+fbiQB4YK7M56sqn5i6iVt/dep2ygPtPr6Wh2XsARGdCbojBrpDw86s +pF5BssrGYEtJsIUbO0FuYoYpigijAdFT5Lv/sKFpJDxYfc9RxszpDJILvuD13toxhufa9iklox tz5VzZaG48OzwVvPeFXW0PZPWlqIf1zjHvodQ4Hedvb6UKTNstWvHwQxBuaFz2Vf5Rt498KfNZ0 YvifuOmx5vwrDCWl6pem0Yrj3scbp1T5BDur3PkjVWJgunFVsxD69enmjzIuvIR/8J1AkmFIgBT VXgolpVjjbspn1doQvjYy1ynY+M8bIGkwSCY1k= X-Received: by 2002:a17:90b:55d0:b0:39e:6a81:c921 with SMTP id 98e67ed59e1d1-39e6a81c9bbmr14597347a91.20.1790052373331; Mon, 21 Sep 2026 21:46:13 -0700 (PDT) Received: from localhost.localdomain ([2409:8a1e:2e81:7320:3443:b4ea:307f:cc4a]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-3a06e570d9esm937101a91.10.2026.09.21.21.46.10 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Mon, 21 Sep 2026 21:46:13 -0700 (PDT) From: Yuchao Zhang To: Yu Kuai , Song Liu Cc: Xiao Ni , NeilBrown , linux-raid@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Yuchao Zhang Subject: [PATCH v2] md: validate bblog_size when loading v1.x badblocks metadata Date: Tue, 22 Sep 2026 12:46:06 +0800 Message-ID: <20260922044606.30774-1-ndaugoing@gmail.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-raid@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In super_1_load(), when the on-disk feature_map does not have MD_FEATURE_BAD_BLOCKS set but sb->bblog_offset is non-zero, rdev->badblocks.shift is initialized to 0 without validating sb->bblog_size. The same field is validated in the MD_FEATURE_BAD_BLOCKS branch ("sectors > (PAGE_SIZE / 512)"), but this branch bypasses that check. A forged on-disk superblock (malicious storage device or crafted image) can therefore carry an oversized sb->bblog_size. When bad blocks are later recorded, super_1_sync() sets bb->size from sb->bblog_size and md_write_metadata() issues a bio larger than the single rdev->bb_page, reading beyond the page and leaking kernel memory contents to disk. sb->bblog_size is never modified by the kernel between load and sync, and the MD_FEATURE_BAD_BLOCKS branch already validates it, so checking it in this branch is sufficient to cover both paths. Fix this by rejecting an oversized sb->bblog_size with -EINVAL, matching the existing check in the MD_FEATURE_BAD_BLOCKS branch. Fixes: 2699b67223ac ("md: load/store badblock list from v1.x metadata") Cc: stable@vger.kernel.org Signed-off-by: Yuchao Zhang --- drivers/md/md.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 680b34a63cb3..1caa92b40f9a 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -1934,8 +1934,11 @@ static int super_1_load(struct md_rdev *rdev, struct md_rdev *refdev, int minor_ if (!badblocks_set(&rdev->badblocks, sector, count, 1)) return -EINVAL; } - } else if (sb->bblog_offset != 0) + } else if (sb->bblog_offset != 0) { + if (le16_to_cpu(sb->bblog_size) > (PAGE_SIZE / 512)) + return -EINVAL; rdev->badblocks.shift = 0; + } if ((le32_to_cpu(sb->feature_map) & (MD_FEATURE_PPL | MD_FEATURE_MULTIPLE_PPLS))) { -- 2.53.0