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 668D8D2F6 for ; Mon, 19 Jun 2023 10:59:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D67C1C433CB; Mon, 19 Jun 2023 10:59:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1687172375; bh=4sAiuO1XPL71JCvuqk3PQrvdkN6iDcQN3USvTxd2SEY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=p/JUz2HWGLqcZqsyqbzrLQfCoCjp7GO2NgGP1ED6p+XutWgI/dp+eDf16D1Bt0hVa ysvGOmUeo9xepMCEI/oVG302m128gCXuw3++oEaPS+deR5ur2WiWHLdziLL4NqzpT8 plSF5MCyTtHsnQs3y59Tx+XAi3OMddURJdjeKpoE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Li Lingfeng , Mike Snitzer Subject: [PATCH 5.15 045/107] dm thin metadata: check fail_io before using data_sm Date: Mon, 19 Jun 2023 12:30:29 +0200 Message-ID: <20230619102143.645302918@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230619102141.541044823@linuxfoundation.org> References: <20230619102141.541044823@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Li Lingfeng commit cb65b282c9640c27d3129e2e04b711ce1b352838 upstream. Must check pmd->fail_io before using pmd->data_sm since pmd->data_sm may be destroyed by other processes. P1(kworker) P2(message) do_worker process_prepared process_prepared_discard_passdown_pt2 dm_pool_dec_data_range pool_message commit dm_pool_commit_metadata ↓ // commit failed metadata_operation_failed abort_transaction dm_pool_abort_metadata __open_or_format_metadata ↓ dm_sm_disk_open ↓ // open failed // pmd->data_sm is NULL dm_sm_dec_blocks ↓ // try to access pmd->data_sm --> UAF As shown above, if dm_pool_commit_metadata() and dm_pool_abort_metadata() fail in pool_message process, kworker may trigger UAF. Fixes: be500ed721a6 ("dm space maps: improve performance with inc/dec on ranges of blocks") Cc: stable@vger.kernel.org Signed-off-by: Li Lingfeng Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-thin-metadata.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -1778,13 +1778,15 @@ int dm_thin_remove_range(struct dm_thin_ int dm_pool_block_is_shared(struct dm_pool_metadata *pmd, dm_block_t b, bool *result) { - int r; + int r = -EINVAL; uint32_t ref_count; down_read(&pmd->root_lock); - r = dm_sm_get_count(pmd->data_sm, b, &ref_count); - if (!r) - *result = (ref_count > 1); + if (!pmd->fail_io) { + r = dm_sm_get_count(pmd->data_sm, b, &ref_count); + if (!r) + *result = (ref_count > 1); + } up_read(&pmd->root_lock); return r; @@ -1792,10 +1794,11 @@ int dm_pool_block_is_shared(struct dm_po int dm_pool_inc_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e) { - int r = 0; + int r = -EINVAL; pmd_write_lock(pmd); - r = dm_sm_inc_blocks(pmd->data_sm, b, e); + if (!pmd->fail_io) + r = dm_sm_inc_blocks(pmd->data_sm, b, e); pmd_write_unlock(pmd); return r; @@ -1803,10 +1806,11 @@ int dm_pool_inc_data_range(struct dm_poo int dm_pool_dec_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_t e) { - int r = 0; + int r = -EINVAL; pmd_write_lock(pmd); - r = dm_sm_dec_blocks(pmd->data_sm, b, e); + if (!pmd->fail_io) + r = dm_sm_dec_blocks(pmd->data_sm, b, e); pmd_write_unlock(pmd); return r;