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 DB8488494 for ; Thu, 5 Jan 2023 13:06:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 407E0C433EF; Thu, 5 Jan 2023 13:06:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672924002; bh=PFXo/H9XbYNJh+1q5k+Qi4mEA3PvRNfZqjQ98IO1cY8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZNYr++h7oEunvP4/uRYZBSzp0O9gY1YhhyZbhRdv7gJX1ovFn46AutfpSRaLB+JEY ltmVnEY2+P5EJxYqmp+0J7eDU3REZAj4hsdzZbn8wzk3TXwf9gfk4PL9dMcF8i0bOx ZKBQyKByrYq7k422f/oGj7kulZRnzPXH1TKxgsAw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ye Bin , Ming Lei , Jens Axboe , Sasha Levin Subject: [PATCH 4.9 203/251] blk-mq: fix possible memleak when register hctx failed Date: Thu, 5 Jan 2023 13:55:40 +0100 Message-Id: <20230105125344.163848872@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230105125334.727282894@linuxfoundation.org> References: <20230105125334.727282894@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: Ye Bin [ Upstream commit 4b7a21c57b14fbcd0e1729150189e5933f5088e9 ] There's issue as follows when do fault injection test: unreferenced object 0xffff888132a9f400 (size 512): comm "insmod", pid 308021, jiffies 4324277909 (age 509.733s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 08 f4 a9 32 81 88 ff ff ...........2.... 08 f4 a9 32 81 88 ff ff 00 00 00 00 00 00 00 00 ...2............ backtrace: [<00000000e8952bb4>] kmalloc_node_trace+0x22/0xa0 [<00000000f9980e0f>] blk_mq_alloc_and_init_hctx+0x3f1/0x7e0 [<000000002e719efa>] blk_mq_realloc_hw_ctxs+0x1e6/0x230 [<000000004f1fda40>] blk_mq_init_allocated_queue+0x27e/0x910 [<00000000287123ec>] __blk_mq_alloc_disk+0x67/0xf0 [<00000000a2a34657>] 0xffffffffa2ad310f [<00000000b173f718>] 0xffffffffa2af824a [<0000000095a1dabb>] do_one_initcall+0x87/0x2a0 [<00000000f32fdf93>] do_init_module+0xdf/0x320 [<00000000cbe8541e>] load_module+0x3006/0x3390 [<0000000069ed1bdb>] __do_sys_finit_module+0x113/0x1b0 [<00000000a1a29ae8>] do_syscall_64+0x35/0x80 [<000000009cd878b0>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 Fault injection context as follows: kobject_add blk_mq_register_hctx blk_mq_sysfs_register blk_register_queue device_add_disk null_add_dev.part.0 [null_blk] As 'blk_mq_register_hctx' may already add some objects when failed halfway, but there isn't do fallback, caller don't know which objects add failed. To solve above issue just do fallback when add objects failed halfway in 'blk_mq_register_hctx'. Signed-off-by: Ye Bin Reviewed-by: Ming Lei Link: https://lore.kernel.org/r/20221117022940.873959-1-yebin@huaweicloud.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- block/blk-mq-sysfs.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c index 5b64d9d7d147..fc9362e0a118 100644 --- a/block/blk-mq-sysfs.c +++ b/block/blk-mq-sysfs.c @@ -380,7 +380,7 @@ static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx) { struct request_queue *q = hctx->queue; struct blk_mq_ctx *ctx; - int i, ret; + int i, j, ret; if (!hctx->nr_ctx) return 0; @@ -392,9 +392,16 @@ static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx) hctx_for_each_ctx(hctx, ctx, i) { ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu); if (ret) - break; + goto out; } + return 0; +out: + hctx_for_each_ctx(hctx, ctx, j) { + if (j < i) + kobject_del(&ctx->kobj); + } + kobject_del(&hctx->kobj); return ret; } -- 2.35.1