From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794667752; b=pKTElPZ7AVYeTVEJX5iUeBC7VyCA64r0exEpoauNTpOKhaDufujEAWVEzU7kOL/KE58r W+k4+U8WQdsovcZOZBbNSFroVsZ12DAT1oBKt+N1MCUYu3ccVARR2v318bl4D1imN8reM 9S3lJ23b9gX1DyMaUF8fUOod2lvkXxJJrmFORMSf96Vedu5kqNW2bZaj0VWI930uqz/tR wK2jPafNL8ja+nn2wmwMu3YQ7gTJuqt4NbjE8JqtJWU/FHUTXbdZrFuJynBBGbGnGT16P XN5XIlyXqLAzZEII5tbIVBfsp74l5f+blWi+J1mW0sHUzmJFRHBI5/QbBmAIteydI2Q== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794667752; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=FEu2mfq5bJfj6w010Q8gRlOZcF8hb/pEE55HP0S2WUM=; b=fcNSuCGrdBrwYOzVZ3YUyZfq8sx+6Tz49z25aKZA4GFzS4TaFi2KaLcL10W2ir15Y/u5 b92bfJ6o73LGcQbGNhtcHB+NgT5XyHBu9AGpOSLZPXfCsVINTgtp5Mpvjd6igsK+RWVjg N0pkvTBbG7E878TpVxjjVoz/rAxue/KPty4/2kIYAk2GSrsvF5kFeq67atO57ByBZ2tML RXmoUZofcMd/lJEeTIYyKICYmawj9McfSSDJNXogeDjwEoYE3oIjasis5mgpkwhoaVFkt 0lpsU+DB9GhYIZb8VOYKoXoq7yscO3xxrrRUfKVZew5II7maATQTpiiuqHKoyEVkuPQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=BDXt8hDz; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B77BD606A33F for ; Sat, 14 Nov 2026 14:49:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=BDXt8hDz Received: by smtp.kernel.org (Postfix) with ESMTPSA id E85271F000C8; Sat, 14 Nov 2026 14:49:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794667752; bh=FEu2mfq5bJfj6w010Q8gRlOZcF8hb/pEE55HP0S2WUM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BDXt8hDzox52ir88NTrwWdWBNjK7v71OGilNVpoGrG3CVYUphsPLtmw1MxOdDJcKg R5cr6PFuYkyOb91ufKvt53euyuHw5P3xJwH5KAYXFyNbP5jkIozU2XjWrwK85yTgap Ln9E7n9gQaq9ohpkYGfpHMVBNGmyGRirFujLRgzC/ELHWhhxfBuASl/T2aDFVA2vq+ eRGHJvCS0aDjsWQuvICcBRvRg85Q/n+FR49icTWZH04KBrkn035NzLkKXNsCMVaOLl IupPWwP53bnCHUlFA1/cdjrlvCFdby+j4C0yxmfm0nz4vU4h4Jp9lB4pPGeuuAIkdK qUoFMwN9HBEyw== From: Sasha Levin To: stable@vger.kernel.org Cc: Yingjie Wang <1075151112@qq.com>, Christoph Hellwig , Keith Busch , Sasha Levin Subject: [PATCH 5.15.y] nvmet: reject keep-alive timeouts that would overflow Date: Sat, 14 Nov 2026 09:49:10 -0500 Message-ID: <20261114144614.3192989-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261109202305-failed-5.15-96ae13f40ce5@kernel.org> References: <20261109202305-failed-5.15-96ae13f40ce5@kernel.org> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Yingjie Wang <1075151112@qq.com> [ Upstream commit 96ae13f40ce5930cd58c43128e385131476f2a66 ] nvmet_set_feat_kato() and nvmet_alloc_ctrl() convert the 32-bit millisecond KATO from the host to seconds with DIV_ROUND_UP(kato, 1000). The addition in DIV_ROUND_UP() is done in 32 bits, so any KATO above 4294966296 ms wraps around and rounds to 0 seconds. A Set Features command with KATO 0xffffffff then succeeds but disables the keep-alive timer: Get Features returns 0 and Keep Alive fails with Keep Alive Timeout Invalid. A Connect command with such a KATO creates a controller without a keep-alive timer. The converted value has more consumers that can overflow. Get Features multiplies it by 1000, and the timer paths multiply it by HZ in 32 bits and arm a delay that must not exceed MAX_JIFFY_OFFSET. Reject a KATO whose rounded value does not fit all of these. Return Keep Alive Timeout Invalid from both Set Features and Connect. Validate Set Features before stopping the current timer so a failed update leaves its timeout unchanged. Round in 64 bits. A KATO of 0 keeps its current meaning. Fixes: a07b4970f464 ("nvmet: add a generic NVMe target") Cc: stable@vger.kernel.org Reviewed-by: Christoph Hellwig Signed-off-by: Yingjie Wang <1075151112@qq.com> Signed-off-by: Keith Busch [ sashal: adapted nvmet_alloc_ctrl() error handling to return status directly and set req->error_loc instead of using args ] Signed-off-by: Sasha Levin --- drivers/nvme/target/admin-cmd.c | 7 ++++++- drivers/nvme/target/core.c | 7 ++++++- drivers/nvme/target/nvmet.h | 8 ++++++++ 3 files changed, 20 insertions(+), 2 deletions(-) diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c index 7c1fc6310599b..9df4107318ede 100644 --- a/drivers/nvme/target/admin-cmd.c +++ b/drivers/nvme/target/admin-cmd.c @@ -808,8 +808,13 @@ u16 nvmet_set_feat_kato(struct nvmet_req *req) { u32 val32 = le32_to_cpu(req->cmd->common.cdw11); + if (val32 > NVMET_MAX_KATO * MSEC_PER_SEC) { + req->error_loc = offsetof(struct nvme_common_command, cdw11); + return NVME_SC_KA_TIMEOUT_INVALID | NVME_STATUS_DNR; + } + nvmet_stop_keep_alive_timer(req->sq->ctrl); - req->sq->ctrl->kato = DIV_ROUND_UP(val32, 1000); + req->sq->ctrl->kato = DIV_ROUND_UP_ULL(val32, MSEC_PER_SEC); nvmet_start_keep_alive_timer(req->sq->ctrl); nvmet_set_result(req, req->sq->ctrl->kato); diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c index 34e7b86c7d0f9..5dd23446a91a7 100644 --- a/drivers/nvme/target/core.c +++ b/drivers/nvme/target/core.c @@ -1355,6 +1355,11 @@ u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn, int ret; u16 status; + if (kato > NVMET_MAX_KATO * MSEC_PER_SEC) { + req->error_loc = offsetof(struct nvmf_connect_command, kato); + return NVME_SC_KA_TIMEOUT_INVALID | NVME_STATUS_DNR; + } + status = NVME_SC_CONNECT_INVALID_PARAM | NVME_STATUS_DNR; subsys = nvmet_find_get_subsys(req->port, subsysnqn); if (!subsys) { @@ -1432,7 +1437,7 @@ u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn, kato = NVMET_DISC_KATO_MS; /* keep-alive timeout in seconds */ - ctrl->kato = DIV_ROUND_UP(kato, 1000); + ctrl->kato = DIV_ROUND_UP_ULL(kato, MSEC_PER_SEC); ctrl->err_counter = 0; spin_lock_init(&ctrl->error_lock); diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h index 4ab5b5580856e..666f33e010dc5 100644 --- a/drivers/nvme/target/nvmet.h +++ b/drivers/nvme/target/nvmet.h @@ -7,6 +7,7 @@ #define _NVMET_H #include +#include #include #include #include @@ -519,6 +520,13 @@ void nvmet_add_async_event(struct nvmet_ctrl *ctrl, u8 event_type, #define NVMET_KAS 10 #define NVMET_DISC_KATO_MS 120000 +/* + * Largest keep-alive timeout in seconds that can be reported back in + * milliseconds and converted to jiffies without overflowing. + */ +#define NVMET_MAX_KATO \ + min3(U32_MAX / MSEC_PER_SEC, U32_MAX / HZ, MAX_JIFFY_OFFSET / HZ) + int __init nvmet_init_configfs(void); void __exit nvmet_exit_configfs(void); -- 2.53.0