From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [PATCH 2/7] blkcg: use blkg_free() in blkcg_init_queue() failure path Date: Tue, 23 Jun 2015 22:44:08 -0400 Message-ID: <1435113853-12053-3-git-send-email-tj@kernel.org> References: <1435113853-12053-1-git-send-email-tj@kernel.org> Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=G75LPLzg5g8AbQwMleS+XMITmvuAVP+js4TEsar9hww=; b=AklpLIT5ZdDdpVV/SyUhu1uObcA5nFk/i4ILv7XPC+1zGeG0klQbxPDGnO/UNSTrAK 7/xCvyggUydG5pAuL7J4S3MFAxc91OioTXIUussR92DFmKi7A9VZQQQAuKwxQZNFRdit IMWFwgb+KAYAy0G8/CFgBuCEWsuz2AsOFjDr/LieIE4oA+UW6SweC8fQV5qvoDtdvf2h JH3QqcX63UyLBaP2D7XjERX0ILh/IKP6f4XP49cXT/unYJcepF51KZ/qJKIsnrdR1l+r NnwEYzDCDLU44wnmtckj96LOAGk+hPgC823l9egNAX3jjw1Co2s9kywNG5PgHtQ4fE1q jSWg== In-Reply-To: <1435113853-12053-1-git-send-email-tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, avanzini.arianna-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, kernel-team-b10kYP2dOMg@public.gmane.org, Tejun Heo When blkcg_init_queue() fails midway after creating a new blkg, it performs kfree() directly; however, this doesn't free the policy data areas. Make it use blkg_free() instead. In turn, blkg_free() is updated to handle root request_list special case. While this fixes a possible memory leak, it's on an unlikely failure path of an already cold path and the size leaked per occurrence is miniscule too. I don't think it needs to be tagged for -stable. Signed-off-by: Tejun Heo Cc: Vivek Goyal --- block/blk-cgroup.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 1fddbbd..898f560 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -57,7 +57,8 @@ static void blkg_free(struct blkcg_gq *blkg) for (i = 0; i < BLKCG_MAX_POLS; i++) kfree(blkg->pd[i]); - blk_exit_rl(&blkg->rl); + if (blkg->blkcg != &blkcg_root) + blk_exit_rl(&blkg->rl); kfree(blkg); } @@ -886,7 +887,7 @@ int blkcg_init_queue(struct request_queue *q) radix_tree_preload_end(); if (IS_ERR(blkg)) { - kfree(new_blkg); + blkg_free(new_blkg); return PTR_ERR(blkg); } -- 2.4.3