From nobody Fri Sep 25 02:43:47 2026 Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75CAA4C33E9; Thu, 17 Sep 2026 11:29:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.25 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789644553; cv=none; b=lGokgzzzXWpJG9fBzNk++FUXTfnPLaMQZNDiE8ydK+eIMj60hwtJnPgdFesjyafNMEpMUQl3UiAtkMNtGnKhiEYpJWA9OSr7q0nnQ3sGN1zCN6Qdh1dPLTlNiehh0xkRG0DoZ5Gqv3ct+UXDgdWs30XZMv6UF8q07/sePrjOxJc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789644553; c=relaxed/simple; bh=hr6jK7hwe0rYgn9zEYI6gtwkc2fqYVxMGqQQ0mQ0UEQ=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=KruU1dSF6T2QS/hINslGhGh7RyWHNuwGjBErusTuemG2LMaEepYqf4Vee+HQJr/y+5kwSJ2C6LaxpwY9ARqjsDR6fhKDQAx8qR4TpysJPx2mXq//Wh2B8JWuzdhlRFf/seRcq5DVup1rXDEkRkoT9dU4MczY7Aj5qTjGmdgiRfs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from dfae2b116770.home.arpa (unknown [36.110.52.2]) by APP-05 (Coremail) with SMTP id zQCowACXAz78zqtqV5N_CA--.1651S2; Thu, 17 Sep 2026 19:29:01 +0800 (CST) From: Wentao Liang To: agoldberger@nvidia.com Cc: andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, leon@kernel.org, linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, mbloch@nvidia.com, moshe@nvidia.com, netdev@vger.kernel.org, pabeni@redhat.com, saeedm@nvidia.com, tariqt@nvidia.com, Wentao Liang , stable@vger.kernel.org Subject: [PATCH] net/mlx5: Fix ent use-after-free in cmd_work_handler() Date: Thu, 17 Sep 2026 11:29:00 +0000 Message-Id: <20260917112900.2148932-1-vulab@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: zQCowACXAz78zqtqV5N_CA--.1651S2 X-Coremail-Antispam: 1UD129KBjvJXoWxJr15ZrWDXF1kGr48Xw1UZFb_yoW8ZryUpr 4Yqa9rKF1qqFs2yr1xZr4kua4rW393KayUC3WfW3WFvFn5Jr1kKFyrKry8tFW8AFZYgFy2 yr40ya17Jr4FywUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPqb7Iv0xC_Kw4lb4IE77IF4wAFc2x0x2IEx4CE42xK8VAvwI8I cIk0rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2 AK021l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v2 6F4j6r4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxV W0oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv 7VC0I7IYx2IY67AKxVWUAVWUtwAv7VC2z280aVAFwI0_Gr1j6F4UJwAm72CE4IkC6x0Yz7 v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0E0s8F02x267IIx4CEVc8vx2IErcIFxwAC I402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrw CF04k20xvE74AGY7Cv6cx26r48ZrWUJr1UMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E 5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZV WrXwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY 1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI 0_Gr1j6F4UJwCI42IY6I8E87Iv6xkF7I0E14v26rxl6s0DYxBIdaVFxhVjvjDU0xZFpf9x 07bnXd8UUUUU= X-CM-SenderInfo: pyxotu46lvutnvoduhdfq/1tbiDAQNA2qrrJpsHAAAsB Content-Type: text/plain; charset="utf-8" In the two command slot acquisition error paths, cmd_ent_put() can drop the last reference and free the command entry, and complete(&ent->slotted) is then called on that freed entry. Signal the slotted completion before dropping the reference so that the waiter in wait_func() is woken while the entry is still allocated and the entry is not touched after it has been freed. Fixes: 485d65e13571 ("net/mlx5: Add a timeout to acquire the command queue = semaphore") Cc: stable@vger.kernel.org Signed-off-by: Wentao Liang --- drivers/net/ethernet/mellanox/mlx5/core/cmd.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/et= hernet/mellanox/mlx5/core/cmd.c index c89417c1a1f9..2dac131c5f86 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c @@ -998,6 +998,7 @@ static void cmd_work_handler(struct work_struct *work) if (down_timeout(&cmd->vars.sem, timeout)) { mlx5_core_warn(dev, "%s(0x%x) timed out while waiting for a slot.\n", mlx5_command_str(ent->op), ent->op); + complete(&ent->slotted); if (ent->callback) { ent->callback(-EBUSY, ent->context); mlx5_free_cmd_msg(dev, ent->out); @@ -1007,12 +1008,12 @@ static void cmd_work_handler(struct work_struct *wo= rk) ent->ret =3D -EBUSY; complete(&ent->done); } - complete(&ent->slotted); return; } alloc_ret =3D cmd_alloc_index(cmd, ent); if (alloc_ret < 0) { mlx5_core_err_rl(dev, "failed to allocate command entry\n"); + complete(&ent->slotted); if (ent->callback) { ent->callback(-EAGAIN, ent->context); mlx5_free_cmd_msg(dev, ent->out); @@ -1023,7 +1024,6 @@ static void cmd_work_handler(struct work_struct *work) complete(&ent->done); } up(&cmd->vars.sem); - complete(&ent->slotted); return; } } else { --=20 2.34.1