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=1794279577; b=2UYoqn55MsI+SfbnmfhmAG/AEZw93GFydEcj9u0RrBUEpeX6TRfnqlni+YhUUKwQzLRW ggqWaeSjD8ZXngYjDwI6uXztfLKpFgFu51sOD9w5MJ9UBibgZOMZZ1iqu2sPhHz/3U+g5 Q2pa/aKVi3abDPTZeBiEYsFmbW1TiHBtBgN2epG03v/2TfPicEjn9h/pJrRCk5xaE0Lde Jky/8DzltYjj25YwWNY3kcZmg+2K/2Jt8fDSYJlq4KY7tbznR+YkTEr2ItOWudHd099or /VIK4z2gxZJs+Ylmv6+oijkuo4M7igv+ACNhDy4Fc1D6IO8kGQxSyIYbdh4AXWWoJmQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794279577; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=ZeryhIiPWCTdnjrmEcUqpvHl6bFeoAvGE/90ly4u5Jk=; b=ZIMKOctDBSMvI/8nN/MS9V37izWR6UWYa4sqA/i2MuaB2cbk4HEfCUbfq5hdmkzszTNe 5ejaMQmfNV/rKOiHuH4GZAkia7FcPuJ1Xmx3gcvzanSCjJ1rB//i4lGRx2XzkGCTTzPfy y7bMK+qjsbJ4YYZ2FBrQCu89psiT1I7Gu4DowdXISK44hXamXFvjP/hxBWnC46zddigdW tDo6f9KCSsN4SKaBItLlUiTiVf8p10ZOqx/V5kzS5BkGuBZvn+0qkUln8IrstWLxLMGIi GyZvLYISDbLdMbzD+OCfUtgO5BGFVPRnKAz9ilcDetFvtT1YczzYcY1f+T9UdxxLKQQ== 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=Ca3KqGJZ; 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 CB6EF606A325 for ; Tue, 10 Nov 2026 02:59:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Ca3KqGJZ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 870701F0089F; Tue, 10 Nov 2026 02:59:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794279576; bh=ZeryhIiPWCTdnjrmEcUqpvHl6bFeoAvGE/90ly4u5Jk=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Ca3KqGJZszybAd/Vj5mhtfwuFaN4hMoAHB1eSRnFCmIPyIXUIOLPe9lHwZAc8px3V rEfKV0goP6tV6P3233sZkOvnYFmHC5xBXnOdG4JydDd2Lrda7Chfq4ilMwyzuR0nRO pPlgocIieGo5sN4Ez1vNKwaG7rkejS5gdSwVsG8DzdPogcN0yOznhHsVWBELcCu3HY FB/BimrSDVczBCX7APZUsYkDohIFQxA+ejNUYAB/SGYuZ+/ky+ZNN9Jz3jI7ESo+/p 0xBAWDWvQlWvYaxW8isTkl8oyrcEdXapPHYWbkd0yEX7OcofHzLP2Hj/7TfbV1Y3vJ syQ4kJcbPBUSQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v7 3/4] usb: gadget: gadgetfs: prevent ep0 event counter underflow Reply-To: sashiko-reviews@lists.linux.dev To: "Jing Lin" Cc: linux-usb@vger.kernel.org In-Reply-To: <20261110-gadgetfs-v7-v7-3-6d05409cc61a@gmail.com> References: <20261110-gadgetfs-v7-v7-0-6d05409cc61a@gmail.com> <20261110-gadgetfs-v7-v7-3-6d05409cc61a@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 10 Nov 2026 02:59:36 +0000 X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Jing Lin >=20 > ep0_read() snapshots dev->ev_next, drops dev->lock while copy_to_user() > runs directly from dev->event[], and subtracts the snapshot afterwards. > A concurrent disconnect, connect, setup, or another reader can reset, > deduplicate, or consume the queue in that window. This races on > dev->event[], can drop newly arrived GADGETFS_SETUP events, and wraps > dev->ev_next if the queue shrinks below the snapshot. >=20 > Dequeue the events into the local buffer and update dev->ev_next before > dropping dev->lock for copy_to_user(). >=20 > Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") > Cc: stable@vger.kernel.org > Signed-off-by: Jing Lin Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261110-gadgetfs-v= 7-v7-0-6d05409cc61a@gmail.com?part=3D3