From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f44.google.com (mail-pj1-f44.google.com [209.85.216.44]) (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 B9DC72C08D4; Fri, 18 Jul 2025 11:54:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.44 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752839666; cv=none; b=Z5RURl+dmCrEyOyILZb4gYax8PXuUxV9FZVF9iJCNOpnzyW6beJ8kTLYCaOWQmPDnGfbcySQ994BGyNnouJb4+sOKXfzqqUtueWeQfJ3RYIF4voC1hIqLauOoZP5iweLGpItbAVLXZ9Xwur6MATBPDNeOtZJyePqNT5plwqrBtM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752839666; c=relaxed/simple; bh=UN0O+pIQg6Glg8Oua8IzJCVXQa4h97piXys6CU6sOBE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=KlAwy5gBDefdSli2wrxfxlx5q5KRsnx0evBkv0Axuwk0v0WO/uVqo4EdVLr5/TkeIEENYXgAPwWU04jOOhKPiP8MmKmsOzvVQcmHXeTJjDGZcoEa+dX2VKm8PYqaYzEDSeBhKvd3jkcdqdAuCNvqgu7TLTIlIlxu+R4h9d8wzSU= 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=VeiVE1Tq; arc=none smtp.client-ip=209.85.216.44 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="VeiVE1Tq" Received: by mail-pj1-f44.google.com with SMTP id 98e67ed59e1d1-311da0bef4aso2114806a91.3; Fri, 18 Jul 2025 04:54:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1752839664; x=1753444464; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=FUjZ1QjCwxsShFOjEqW/dcUlvmZBvKECdHobMCf4NrQ=; b=VeiVE1TqJPlKHcVbS7p/dYtvUChHsS5taYjKtf5nR5LY7DdfRkD/OU6cbZA56ciU8k 602nL9gV/ASBrKGWmLbhSZgQChZwpZHJNIJmL16uIuM9aSzNymQ4B2FWK8zHQIfkayjO x2HUKLHuLB3GUibToUTgv/ge22IuOda+79x9URzj4WXOAVZZfGjX3FFHLWSBLsKWI3h6 WvGvZlfJcwQLu/Lu+tt/0yhfMRuG+ipK0y5H50kBcPpOFLUnqPv0e96aMrw5Hk67KVQh P/rOOEVas39SF2wf8ZkZ9CSRJbTvkRiZfWuKsgJgtnVJ9bm7Vc2Oge8afTvZ8SRcUl5e A4KQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1752839664; x=1753444464; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=FUjZ1QjCwxsShFOjEqW/dcUlvmZBvKECdHobMCf4NrQ=; b=GilfWKDUPhZlWaMVm2De7w3X7KNJf/Tm5j0gdUUR1H4NfN+pWplScgllEcHKq6JyY7 Zfnv96d4+zLVLAMpiUrWa7mK/397QVY2woBzg+R32RrCT9TiY+MD9iPmmxuWUxgwNeHg VzC4QKsTPKW0WZfzKtpar81aTU96FpC/JHJ5Au6CiPeex5642/rW+NENF5FKrl9qHtJq nnXhbmpwTWJ7e2Ypihjg31rv96P3UZ+2XLB+5iN2TGw7kpX/3rANKpHDRrJGDK+LkB0L bGwKxLBycb4V0cv0Hsk6cab5IFB1ZtnENQiJyoG9Gr5ItcZ2Erp1JhsmkFch58X1Mjpa objw== X-Forwarded-Encrypted: i=1; AJvYcCXJig8Ckihvzk9ZII6BkVtWgl43TiCJRWhKLtIa4+geDyXm6dqThM+dsWfQAwaaSLe6UMJDD/bMbn5CAH0=@vger.kernel.org X-Gm-Message-State: AOJu0YydJcztRV6nRpF5R1g5oOl0eq3dTDzfZLy2InnRxk6Y6wRx/rwp goY2af5ecHXRrtHsGYM6QF/ZG0A5qe+7yXMHsD6vkuFYDGXeexR+haab X-Gm-Gg: ASbGnctWih154lOsLYnQTI8u0bQosj9jUEVyci2/caZQ4lxfBdVrHxbPrOQfzgQVVrL 0oEphYTRBSKAPOSDN8dIfW00RIcNdMBOCIL/N790Nt/bKqxg6hUVY2k/G9Yt98lY676rXsC+ZpM LWGDLxHkvrvZOStq+NGt7FF6KKEytC8XiJOCdDJpj/6L52uVFi1OzvBeUb5r6O2EV3QokUELjJK BRdhhwGbKCZer36nrfzq6wOCxLIoml3DsjBqd99emC/pp8iV3Mc9GuJ1HxCOCVixrHVZVph0LPK ziJobVDMw7MRm8OcS2c9CMgF9aqhjgbpEql7sNJK9g9DSXnJPEijZppjDxL9yZ3U5HhO0yAoZEU Csc0FlHZ3npO9zAdUjK+0BpPK+0YG7h1+UlCspALbNUFh/uRqxXXVr1Au+uA= X-Google-Smtp-Source: AGHT+IGOdF3rwJ/FyhT1NPmrh0q9I1qR7G4EWEQsBJZmzFqdyODx/5SLyLos+cfm+vOtOuDp7IVY6w== X-Received: by 2002:a17:90b:4fc4:b0:311:c939:c859 with SMTP id 98e67ed59e1d1-31c9f44dca6mr13660879a91.30.1752839664102; Fri, 18 Jul 2025 04:54:24 -0700 (PDT) Received: from localhost.localdomain ([14.22.11.161]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-31cb603aee1sm2729890a91.30.2025.07.18.04.54.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 18 Jul 2025 04:54:23 -0700 (PDT) From: Zijiang Huang X-Google-Original-From: Zijiang Huang To: tj@kernel.org, hannes@cmpxchg.org, mkoutny@suse.com Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Zijiang Huang , Hao Peng Subject: [PATCH 1/2] cgroup-v1: Fix missing mutex_unlock in error paths Date: Fri, 18 Jul 2025 19:54:08 +0800 Message-ID: <20250718115409.878122-1-kerayhuang@tencent.com> X-Mailer: git-send-email 2.43.5 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In the function, after acquiring the mutex with mutex_lock, multiple return paths (such as returning ERR_PTR, NULL, or normal pointers)fail to call mutex_unlock to release the lock, which could lead to deadlock risks. Signed-off-by: Zijiang Huang Reviewed-by: Hao Peng --- kernel/cgroup/cgroup-v1.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c index fa24c032ed6f..73e0fd93111a 100644 --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -423,8 +423,10 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos) */ if (!ctx->procs1.pidlist) { ret = pidlist_array_load(cgrp, type, &ctx->procs1.pidlist); - if (ret) + if (ret) { + mutex_unlock(&cgrp->pidlist_mutex); return ERR_PTR(ret); + } } l = ctx->procs1.pidlist; @@ -443,11 +445,14 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos) } } /* If we're off the end of the array, we're done */ - if (index >= l->length) + if (index >= l->length) { + mutex_unlock(&cgrp->pidlist_mutex); return NULL; + } /* Update the abstract position to be the actual pid that we found */ iter = l->list + index; *pos = *iter; + mutex_unlock(&cgrp->pidlist_mutex); return iter; } -- 2.43.5