From nobody Wed Jun 17 07:35:34 2026 Received: from ha.d.sender-sib.com (ha.d.sender-sib.com [77.32.148.27]) (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 47D0535BDC9 for ; Sat, 25 Apr 2026 11:31:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=77.32.148.27 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777116671; cv=none; b=AwS455I88h0M+GLabCIDNjthLuknsgMHAS/V0bn5C6U6NfmudHCEu7B/v7uSBwfd/ls0Q7mlnlx7nk2KzVdd3PQLgnJXDe6BxXvknXd4AQLEDh/XpGnsmWqqLQptBc/1xwLpKBjJ+2aYwkqGlCIAL+Vw9FX0+E//rOfcj/1XSkw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777116671; c=relaxed/simple; bh=Ql2A8yFn+4ufdzeFIw64rWNupDI/jRZkOBoo19GJ4fI=; h=Message-Id:From:To:Date:Cc:Subject:Mime-Version; b=J++C9qpJ1Lpenkw/xyCx5mWc8LgMJ3ya0tKPN9NYwvTxgmTUvWMvdHdKtVmBjDUjnOaz41MZCo0BiySjPp7tgS5nM+ax7sJM4FiZQi0r/xFcZzk7MaeYCrqbB8MoLTyRL0zMAOhBV5zYGrp4X3KWIpul998Z5xAhz/h8jNY5lw4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=unknownbbqr.xyz; spf=pass smtp.mailfrom=ha.d.sender-sib.com; dkim=pass (2048-bit key) header.d=unknownbbqr.xyz header.i=@unknownbbqr.xyz header.b=RV+oE4Ag; arc=none smtp.client-ip=77.32.148.27 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=unknownbbqr.xyz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ha.d.sender-sib.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=unknownbbqr.xyz header.i=@unknownbbqr.xyz header.b="RV+oE4Ag" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=unknownbbqr.xyz; q=dns/txt; s=brevo1; bh=tjpiqEV3lHntAue4V3umDyply7Iht+6lSvFDgIM1nrA=; h=from:subject:date:to:cc:mime-version:content-transfer-encoding:list-unsubscribe:x-csa-complaints:list-unsubscribe-post:message-id:x-sib-id:feedback-id; b=RV+oE4Ag7vQT3Ze/WHWi3Re+aNxJWWnWJneDcPbz+mfOza58pQdSUrJBdjTPj6nSDTJIZBwJXNXL 4up9jvJC9uEYJRcP6Sj7xvGKuixRLtgENGZf2s38AVLF2JWFb01QFlySA+cmosR0/e4usJpaALHO YzGvdQEBwosM+QjHgqGttlmfQmMvuNov0AHDxIsoEsAAEDBD32aygZb1xFJmh/ofUoNegWjkNJd0 uiOK22JIqDv/gX3Kp3311cVmI0ImnB6IKJvS6nZK4ZD7WRS2Fzb/mf3ppDhoaMvhV1IS/gBo1fQg ErA2at53VaS12mJdIGb1kQtwJY+AVN4QMEiqFA== Message-Id: <5799f233-2ead-448a-97c5-7839a7ea642a@smtp-relay.sendinblue.com> Origin-messageId: <20260425113057.178-1-dev@unknownbbqr.xyz> List-Unsubscribe-Post: List-Unsubscribe=One-Click Feedback-ID: 77.32.148.27:10473219_-1:10473219:Sendinblue From: "unknownbbqrx" X-CSA-Complaints: csa-complaints@eco.de X-Mailin-EID: NDQzNzMzMzgyfmxpbnV4LWtlcm5lbEB2Z2VyLmtlcm5lbC5vcmd%2BPDIwMjYwNDI1MTEzMDU3LjE3OC0xLWRldkB1bmtub3duYmJxci54eXo%2BfmhhLmQuc2VuZGVyLXNpYi5jb20%3D To: Date: Sat, 25 Apr 2026 14:30:57 +0300 Cc: , , "Ali Ahmet MEMIS" Subject: [PATCH v3] tools/power/x86/intel-speed-select: Harden daemon pidfile open X-sib-id: -0dUqeB2aIDsgZa2fAesvPqU9u2A0ZXaAPF7HntGSO5WhlX9hBPYpTNCnpdQudryqxhhnXoHBNdSu69sGU72sUSgZ5KnfHaAOE3A3vaKCZO7CsiSoINdu13KJMRYW6NJidNTP7G6YJ-LIyVp_lP8GJpgPkSp288aKLrzrSXDLBpMhO2yhVt6KMcE9g Content-Transfer-Encoding: quoted-printable X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: Ali Ahmet MEMIS Avoid symlink-based pidfile clobbering by opening the pidfile with O_NOFOLL= OW and validating it with fstat() before locking/writing. The daemon currently uses a fixed pidfile path under /tmp. A local unprivil= eged user can pre-create a symlink at that path and cause a root-run daemon= instance to write into an attacker-chosen file. Signed-off-by: Ali Ahmet MEMIS --- tools/power/x86/intel-speed-select/isst-daemon.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/tools/power/x86/intel-speed-select/isst-daemon.c b/tools/power= /x86/intel-speed-select/isst-daemon.c index 66df21b2b..acedb7432 100644 --- a/tools/power/x86/intel-speed-select/isst-daemon.c +++ b/tools/power/x86/intel-speed-select/isst-daemon.c @@ -148,6 +148,7 @@ static void daemonize(char *rundir, char *pidfile) { int pid, sid, i; char str[10]; + struct stat st; struct sigaction sig_actions; sigset_t sig_set; int ret; @@ -200,11 +201,17 @@ static void daemonize(char *rundir, char *pidfile) if (ret =3D=3D -1) exit(EXIT_FAILURE); =20 - pid_file_handle =3D open(pidfile, O_RDWR | O_CREAT, 0600); + pid_file_handle =3D open(pidfile, O_RDWR | O_CREAT | O_NOFOLLOW, 0600); if (pid_file_handle =3D=3D -1) { /* Couldn't open lock file */ exit(1); } + + if (fstat(pid_file_handle, &st) =3D=3D -1) + exit(1); + + if (!S_ISREG(st.st_mode)) + exit(1); /* Try to lock file */ #ifdef LOCKF_SUPPORT if (lockf(pid_file_handle, F_TLOCK, 0) =3D=3D -1) { base-commit: 2e68039281932e6dc37718a1ea7cbb8e2cda42e6 --=20 2.53.0