From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 767D51DF26B; Wed, 6 Nov 2024 12:18:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730895496; cv=none; b=Hclni6/Qb7ItFzb7c5S/VauaXbm1tKf48bg0Nb06lSVfyE5NsGNezqTmX8VcMQeOczQODyPz4ttpeL2oIHMFDCF6jSyXGu/eD2Jxv8VZR0viPf/jxl3Zhb+v/0MastOlz8WSivvlxaoApNs8679dPBuS6Udha+it3maWXoeAMyM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730895496; c=relaxed/simple; bh=+bC58XwPsgNLZw729qNnECxDmU5Eev6pMVUXq+YxS+Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cCWrviVL3k6s/MQe2KfL18aTIB5fiTyw6FrFweGccbg12kSOh9OTWmrRZ6FaeIHKZ5kLrOpcMM2UojhNW9T9IL6/JW0Rimki3qGSElEikZK39MrIVRl0l/XN1EOXD3Ybk+mpBgLwZTRJQF8Kz1lIMUDdtcBDbA3q9zkBJD3LBWQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NAmPaOxk; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="NAmPaOxk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F3E5EC4CECD; Wed, 6 Nov 2024 12:18:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1730895496; bh=+bC58XwPsgNLZw729qNnECxDmU5Eev6pMVUXq+YxS+Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NAmPaOxk/hY8DVkEgAttTfb2HTQ3lwcK55V6hChGlY3rWHNt0JEHSwWf+tU6k25pI bn9Eh/Sg/eHbbFnM+5hSQCSXSI5ebKsw1iANNK/b0HKDznl4Vwf+ONov0b9pwLzY1X inEoil6Vc35cABAz7K3yoRpvHsGZzgiFNgL69AEw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alfred Agrell , Tetsuo Handa Subject: [PATCH 4.19 210/350] tomoyo: fallback to realpath if symlinks pathname does not exist Date: Wed, 6 Nov 2024 13:02:18 +0100 Message-ID: <20241106120326.177404036@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241106120320.865793091@linuxfoundation.org> References: <20241106120320.865793091@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tetsuo Handa commit ada1986d07976d60bed5017aa38b7f7cf27883f7 upstream. Alfred Agrell found that TOMOYO cannot handle execveat(AT_EMPTY_PATH) inside chroot environment where /dev and /proc are not mounted, for commit 51f39a1f0cea ("syscalls: implement execveat() system call") missed that TOMOYO tries to canonicalize argv[0] when the filename fed to the executed program as argv[0] is supplied using potentially nonexistent pathname. Since "/dev/fd/" already lost symlink information used for obtaining that , it is too late to reconstruct symlink's pathname. Although part of "/dev/fd//" might not be canonicalized, TOMOYO cannot use tomoyo_realpath_nofollow() when /dev or /proc is not mounted. Therefore, fallback to tomoyo_realpath_from_path() when tomoyo_realpath_nofollow() failed. Reported-by: Alfred Agrell Closes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1082001 Fixes: 51f39a1f0cea ("syscalls: implement execveat() system call") Cc: stable@vger.kernel.org # v3.19+ Signed-off-by: Tetsuo Handa Signed-off-by: Greg Kroah-Hartman --- security/tomoyo/domain.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/security/tomoyo/domain.c +++ b/security/tomoyo/domain.c @@ -701,10 +701,13 @@ int tomoyo_find_next_domain(struct linux ee->r.obj = &ee->obj; ee->obj.path1 = bprm->file->f_path; /* Get symlink's pathname of program. */ - retval = -ENOENT; exename.name = tomoyo_realpath_nofollow(original_name); - if (!exename.name) - goto out; + if (!exename.name) { + /* Fallback to realpath if symlink's pathname does not exist. */ + exename.name = tomoyo_realpath_from_path(&bprm->file->f_path); + if (!exename.name) + goto out; + } tomoyo_fill_path_info(&exename); retry: /* Check 'aggregator' directive. */