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 2A77923B616; Mon, 22 Sep 2025 08:50:21 +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=1758531022; cv=none; b=DyCfSZY8hqYhjwOTXlPu2bki+OYpj1OKxAiUFZn2i8Zaq3if2KdkPOlVoeq6gLnnEsgfI/2TLqM/gu5sdnTtb7LQLDEpEikR4w9f7F3eAE/GKg0V0thUo6J97viIHa6v8ZM0uxFi8C0OggxnkFmmsCjqWvxkX9pAkGnKXbfYZlY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758531022; c=relaxed/simple; bh=3LiBLlWVvFCy5klUJ+cPajsUi3HC6fr8Tl8FH/qHaac=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=soCTwNeGKO8qSeKNmTQdANF7c94WnAeJWFpvS193+uvD0V6cST6rr9MKeCcdePx2M0I8CTYmmc6Bvj2tcA+u22f2ao1eOh0zmu0JvmccnCHjiJbjT4lt1Pzs1A+KBbira9lOrY4mQteLdqbsBSpxGe+k8848UEN9Ygzdf2sOlJw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AU/P3ygy; 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="AU/P3ygy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 60413C4CEF0; Mon, 22 Sep 2025 08:50:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758531021; bh=3LiBLlWVvFCy5klUJ+cPajsUi3HC6fr8Tl8FH/qHaac=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=AU/P3ygynrdzgQwEX0PEavE51C9fuBWO2Z2T34OfzDhViNrVpPkVKiJCcFrsmoZb6 WKe+JcFsQmuTBB2sipJv74gQx1OqwjkdAPYMAzG3+YAH9hkxYu8wDzWkqc88Xgxnag TVE8lRIwlu1OGdCS94LRtWC8B8aJconfMJIzGxnS+DO8S5PV9BEzlBbmsc0jsHcPcc rNoPyS4BRUMZvkQp6LeUDncUpxbqtnSK53uI/86l9Hw4TMmlajXndgU1SDYhnk5HKH Sl46Ms4slzsouDHcjFTioWHFiyp43wUka3CO0IlGRMTtMtbdOrEgUrxJ16Z1QWYf/M 5Q9xLtlBObZeA== Date: Mon, 22 Sep 2025 14:20:14 +0530 From: Sumit Garg To: Jens Wiklander Cc: linux-kernel@vger.kernel.org, op-tee@lists.trustedfirmware.org, Jerome Forissier , stable@vger.kernel.org, Masami Ichikawa Subject: Re: [PATCH v2] tee: fix register_shm_helper() Message-ID: References: <20250922083211.3341508-2-jens.wiklander@linaro.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250922083211.3341508-2-jens.wiklander@linaro.org> On Mon, Sep 22, 2025 at 10:31:58AM +0200, Jens Wiklander wrote: > In register_shm_helper(), fix incorrect error handling for a call to > iov_iter_extract_pages(). A case is missing for when > iov_iter_extract_pages() only got some pages and return a number larger > than 0, but not the requested amount. > > This fixes a possible NULL pointer dereference following a bad input from > ioctl(TEE_IOC_SHM_REGISTER) where parts of the buffer isn't mapped. > > Cc: stable@vger.kernel.org > Reported-by: Masami Ichikawa > Closes: https://lore.kernel.org/op-tee/CACOXgS-Bo2W72Nj1_44c7bntyNYOavnTjJAvUbEiQfq=u9W+-g@mail.gmail.com/ > Tested-by: Masami Ichikawa > Fixes: 7bdee4157591 ("tee: Use iov_iter to better support shared buffer registration") > Signed-off-by: Jens Wiklander > --- > Changes from v1 > - Refactor the if statement as requested by Sumit > - Adding Tested-by: Masami Ichikawa - Link to v1: > https://lore.kernel.org/op-tee/20250919124217.2934718-1-jens.wiklander@linaro.org/ > --- > drivers/tee/tee_shm.c | 8 ++++++++ > 1 file changed, 8 insertions(+) Reviewed-by: Sumit Garg -Sumit > > diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c > index daf6e5cfd59a..76c54e1dc98c 100644 > --- a/drivers/tee/tee_shm.c > +++ b/drivers/tee/tee_shm.c > @@ -319,6 +319,14 @@ register_shm_helper(struct tee_context *ctx, struct iov_iter *iter, u32 flags, > if (unlikely(len <= 0)) { > ret = len ? ERR_PTR(len) : ERR_PTR(-ENOMEM); > goto err_free_shm_pages; > + } else if (DIV_ROUND_UP(len + off, PAGE_SIZE) != num_pages) { > + /* > + * If we only got a few pages, update to release the > + * correct amount below. > + */ > + shm->num_pages = len / PAGE_SIZE; > + ret = ERR_PTR(-ENOMEM); > + goto err_put_shm_pages; > } > > /* > -- > 2.43.0 >