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=1794066959; b=37f+Y3opasAUXMW2mMm0FuWxbkog80m85+t/7ayCERVF7l619KnGzY8XGska2quq+EYz LqzvqSbqcsm+3nXFWEdF4Vc3uXtfu0AzfDEJmZ86skovrMZFlzcf3915V1OiHHIh/bDcu cOb0Z8p84fxC5fM+PW1ykeQ9PRSR0VA05AmDKGGaOmf8oesafZvHt9fub8IglLh4MBF4h ByM0VfpobhZzaCC2y/AM4fc2yIosqDwmOKowwSQw/0r26mSfUkerWvEPFH4B2IvwQoVDs AK6AK4inQ4q1OZr+ImqXywq//lSRXVsfkp9SuWqTMvcUZe2dRAr9uMBlWxYa03fON1g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794066959; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=83h62mGO7UoY2PmdY1QMZ35Sjt1U6B+DnOerehftN6k=; b=iY2ua6P0TYp0+W5zQYY9V3n55FhgXaUxUj6wQgCrqHxlrqc0dMnFJuYt55h+C0pP4dWX RFRKQZSsQIygjWI9KnuSWo6l3moPtWjoasklBZU6CY+mCotH6/a39RXZhjeJAo7AW0/ON cpFE76qMQLI2BvXEKH9XQv/jQJiitudkM9LdaumRaA/dwZWMljIAAS4HNaI5zlrFQVbAv qrwuictDGYAdhGaAjdDSoWYmkU5gV7Je+lyfLX2SrDTF50B+X5xKnHdQL1F6znrrK3Qf6 uvNp4CDc+q17A512HZAbPReKpPbwSxkwrvkyAlWwzYJHHnZjMu6LA/OwFEPFNd1aQ6w== 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=g+d7P8uD; 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 68758606A326 for ; Sat, 7 Nov 2026 15:55:59 +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=g+d7P8uD Received: by smtp.kernel.org (Postfix) with ESMTPSA id CAE861F0089F for ; Sat, 7 Nov 2026 15:55:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794066958; bh=83h62mGO7UoY2PmdY1QMZ35Sjt1U6B+DnOerehftN6k=; h=From:Subject:Reply-To:Cc:In-Reply-To:References:Date; b=g+d7P8uDHtQ13HIN4ejW8oVK4WKOUiE6Exe85fYcFah2FH6ae6CZ0k1OqLAU/tegZ WcwG9R0VZHSI2aqClJqSZr5roHxWZeRHXIKRwwwNEwT8342Vlu679+WU/XXIK9Fr85 hbGimPiBR42FmY73fHi+qT4Qz/KwXzzfReY2tnhFtAHKoWtE1NXr1Nfm6k0XRgMyET I5esqB18uwozC4unrCkK/TIlk1USqv7f9lJHoOz88b0F2zM/0BiyYmZkcjjDsvZrb/ Z9rsIwIMZCQvP+Ruo8B3vvLjZ6hpWE5yFxnhezs4XMejyXLHDgHbKIRQfbXaVZfK4l G5lS6gB5ZaLzA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [RFC PATCH 2/2] fcntl: recheck signal permissions before falling back to SIGIO Reply-To: sashiko-reviews@lists.linux.dev Cc: linux-security-module@vger.kernel.org In-Reply-To: <4C916018FDDAFB60+20261107154928.3519030-3-shilc2025@mail.sustech.edu.cn> References: <20261107154928.3519030-1-shilc2025@mail.sustech.edu.cn> <4C916018FDDAFB60+20261107154928.3519030-3-shilc2025@mail.sustech.edu.cn> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Sat, 07 Nov 2026 15:55:58 +0000 X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > F_SETSIG allows a file owner to request a signal other than SIGIO. > send_sigio_to_task() checks permission for the configured signal, but > if queuing fails, it falls back to SIGIO without checking permission > for the fallback. Permission for the configured signal does not imply > permission for SIGIO. >=20 > Recheck permission before falling back from a different signal to > SIGIO. Keep the existing behavior when SIGIO itself has already been > checked. >=20 > This was reproduced on x86-64 QEMU/KVM with AppArmor file signal > mediation added: a recipient allowed a real-time signal but denied > SIGIO reception and set RLIMIT_SIGPENDING to zero. Queuing the > real-time signal failed, and the denied SIGIO was delivered. With this > change, the fallback SIGIO is blocked; allowing SIGIO still permits > fallback. >=20 > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > Signed-off-by: Shi Lecun Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/B01DC8398B429509+20= 261107154928.3519030-2-shilc2025@mail.sustech.edu.cn?part=3D2