From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f175.google.com (mail-pg1-f175.google.com [209.85.215.175]) (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 0A5C82E2DDD for ; Thu, 28 May 2026 02:48:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.175 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779936538; cv=none; b=NETztN+CWaXmW5HebTajYr9CGSihVY0+aAmQ39z3/5gU18Utm1s884HZKrpNRAhNWk1oy3Cj5Q5hIvbpyehZdu+StGU9CykEcaNqxJbYs19eU7SFgBFqjXsWx1U95444AeKav64Ot9rJJCnnSobbAGgeQ7a3UoZqB0AehVrWijk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779936538; c=relaxed/simple; bh=4ILmcE2UVRvUA5w/bCMsuoZ6029LYusklIg66JvviMc=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=DUY0+IISAPQ6eonJ53k3y8h10smJKv6QkkPlQ7qdJcdUV/oxu7CIbZ6n6HHBKWG5zGC2fTJZYWuvTry83OUiQg5eH/88bacaHvLnfDvcR79DYNuTngnviORBGLgEPXPlhjrsuvlzFu4fz9Cbv36J5QTfyGcKaA4S48E6tBZmpAE= 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=T5U7ChHy; arc=none smtp.client-ip=209.85.215.175 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="T5U7ChHy" Received: by mail-pg1-f175.google.com with SMTP id 41be03b00d2f7-c796163fac5so9544603a12.1 for ; Wed, 27 May 2026 19:48:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1779936536; x=1780541336; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=UdZHIVC8VqdiF0LxnTx3Ka4A/RjNztw5bpRG2RMXPPI=; b=T5U7ChHyEZhxolxb0MDGheEdL2EnsmL94QT1nbR4/jfJv3CfiyzggSxIVzszeOVtdw IL9/fhUf1pHx2ZfARCbIRcw1fYW/smBXRp/1hqvNZ/2YbrDSjjXi2r1O+OYfsX3iE+lj Q7FdHlLkao4e6kEHZ9kKBrQzHXZMtu2BH3jJAWFgv+OzeSBY/PP1UZTJYNRJq1gMtxhk pNFk7Ytfe0lZMoI1RdZ+HUWf1PBFDDDwCdcjrsS1xGNo6XFbH82ZiGH7kpm/ri1wPUmY 25TWRxYM3Csw+e/YrVkc2UYMmH7NTNiKCkpHbQbrDUHfsmwIohUb1lomLhje3CgO4pP3 hIgA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779936536; x=1780541336; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-gg:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=UdZHIVC8VqdiF0LxnTx3Ka4A/RjNztw5bpRG2RMXPPI=; b=VmrFXjhToHOa7+KRQ7YHNRlT4XSAdX3hQOteAfPVtcGJGxiWrz/rfYnRTrIrXBqanY /FhilfFkAkN/w3rKGH5ROng8HBFlMtEexfN9jkv06BxQmchMpiGob1IXtU6GtKxPgtDh bwfSo++QG8iNaDHINk/8CukTv5v5C2TH/h3LLqmvtEt/6VbsYIWR/WNPjHXRygK+m7bh 77djcTNQ5PuFbA2kxLEfRPP7wmCdslCFYiE2+v2Av+41TGRv8e8lGW1BjC9fqoN5QdRw Gw4xNSQfzIQVgd4iC9GVM9Kf1YAclXXKueIV/qvX0oXsQyozr93r1GC/QtJ0lbtQIHAN ZtlA== X-Forwarded-Encrypted: i=1; AFNElJ9BH49F9n+MypCyuloufBD5Jo2adGNfq66k3QhToO8kECh/5BKRlJ+xjfUBWRnzI/qhktPwgJHyDn7cxg==@vger.kernel.org X-Gm-Message-State: AOJu0Yx4JDM2eFA/t3cD23Zw1RnSt4kRhhvUNh/hL4VqA7PAIblncM2y 6mOnxWLD7+cKrUx6aMhRktc9IKbg4V8Anis8YIxLCpjv1Z1CIWKi3Xh8 X-Gm-Gg: Acq92OGGszjrckrbjSB9HBg/12Iwz/UAeTdXxeaLsVt0LCUU8Ab0mF7Bzr/8hszYTAC Y33ZFlLK9cWYx1W7LS+dyRIHrDU/BW2id7DL8RlvDcWV49rFKJePeYqv2Owgl509MW5fae7PM+U LA4Vh2AG2J1ldBjzS+re/LdgM+yen5EVqpLGmt5fefC0xZeDoqgk7TCs3JcSx5ElohHnOaMlqOr thCTHQNjUNvfzdn8/3ov8ElWnaSS7FE3/7bbqTCw3/pjSyErGPUp+x8GfZlNO5YZx5McZdJebwT 5MvVLCb97OQPtc3Ao48XktQBtUTwjTtddKPKUWfHUjwX6nfqpcnj08G4KS8S9GCffmvv+DWMvPS AWJu4fIjqcFtzUxP8OP8cj1IIkSjFz4GA0YIOossFfFUeIuWXeZq1uVwT8Hb+cDuAdYJwRI44Ei 3iZJanD7TqC/xDTl9u10uJEruohvCjBtotGg== X-Received: by 2002:a05:6a00:238b:b0:835:5aa3:2dab with SMTP id d2e1a72fcca58-8415f1236aemr26567785b3a.6.1779936536313; Wed, 27 May 2026 19:48:56 -0700 (PDT) Received: from [127.0.0.1] ([116.80.91.208]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-841f3cbcddbsm366877b3a.4.2026.05.27.19.48.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 27 May 2026 19:48:56 -0700 (PDT) From: Cunlong Li Date: Thu, 28 May 2026 10:48:44 +0800 Subject: [PATCH v3 1/2] zram: fix use-after-free in zram_bvec_write_partial() Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260528-zram-v3-1-cab86eef8764@gmail.com> References: <20260528-zram-v3-0-cab86eef8764@gmail.com> In-Reply-To: <20260528-zram-v3-0-cab86eef8764@gmail.com> To: Minchan Kim , Sergey Senozhatsky , Jens Axboe , Andrew Morton , Yisheng Xie Cc: Christoph Hellwig , linux-block@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Cunlong Li , stable@vger.kernel.org X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1779936530; l=1542; i=shenxiaogll@gmail.com; s=20260517; h=from:subject:message-id; bh=4ILmcE2UVRvUA5w/bCMsuoZ6029LYusklIg66JvviMc=; b=KynYLGaGfZewjfo8RGU3mhyIy/vlwWxgy9oFeOCxoXHK2kYgK2sfLrwnBPEM449prqRHxV4Ff gobRxeZpMNpCc9MhH6mBms/BlpM1EFCtEHdF4CNUFQvLFVvO0SNxIr4 X-Developer-Key: i=shenxiaogll@gmail.com; a=ed25519; pk=SKFifnqPdsvsjuhUiq+Y9vtCdhyZ/LrRcfYn8eRq6AE= zram_read_page() picks the sync or async backing device read path based on whether the parent bio is NULL. zram_bvec_write_partial() passes its parent bio down, so for ZRAM_WB slots the read is dispatched asynchronously and zram_read_page() returns 0 while the bio is still in flight. The caller then runs memcpy_from_bvec(), zram_write_page() and __free_page() on the buffer, leaving the async read to write into a freed page. zram_bvec_read_partial() was switched to NULL in commit 4e3c87b9421d ("zram: fix synchronous reads") for the same reason; the write_partial counterpart was missed. Fixes: 8e654f8fbff5 ("zram: read page from backing device") Cc: Christoph Hellwig Cc: stable@vger.kernel.org Reviewed-by: Christoph Hellwig Reviewed-by: Sergey Senozhatsky Signed-off-by: Cunlong Li --- drivers/block/zram/zram_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index aebc710f0d6a..b23a8bbb687c 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -2333,7 +2333,7 @@ static int zram_bvec_write_partial(struct zram *zram, struct bio_vec *bvec, if (!page) return -ENOMEM; - ret = zram_read_page(zram, page, index, bio); + ret = zram_read_page(zram, page, index, NULL); if (!ret) { memcpy_from_bvec(page_address(page) + offset, bvec); ret = zram_write_page(zram, page, index); -- 2.30.2