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 3495419CCF7; Thu, 25 Jul 2024 14:55:08 +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=1721919308; cv=none; b=Yjofqqhtt2RHRF0iKnoUwftfWiof4seBamZr9iqCX8MgURSi3aml++kUXw3Ct90aARAKFuTn49h2krgWp21Jfn+cUfoKQTqIALGBO6kJQOnjDXb7ceBGKOx9otVr397aQ96ytxIlDNB2tLrIyILR2eb+qT8gp3CGjgGRyaq7zKU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721919308; c=relaxed/simple; bh=zoEtUUu+RiqmdyQ9o4Z2z1ydHz7ItovSsHtaHe+RDZs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CCuvnVtfmWnpPQkSNJ+LnPON9KaHuG2TomY0OBOumSYBMKoLkNC7pFSOYeGRVEClp16wr6UhM58MGpTZ0XeW92pa68fU2+S3Nb28fvSdWDQtDtkm3QRanOtkj8lSxtbAzFAlaCzRGhnHcCN5Cz5mxWxJY5DDb2z5pVxsvvu5aUk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2czUr/T8; 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="2czUr/T8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B272BC116B1; Thu, 25 Jul 2024 14:55:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721919308; bh=zoEtUUu+RiqmdyQ9o4Z2z1ydHz7ItovSsHtaHe+RDZs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2czUr/T8nwkUU+YEJu7r+LEBze+huD3kRvrmaOef9kerV9WE00KzeZNySlhQZGYQY XJjnjcq+VV7N3IC7yiJ5YAE2bHpMF6ZAdg0cAezTBwZl4Ht9Qc3b8RZk2pT4K85MXE jJgFuGFesj+9g9Hq5wl/xhYPejgmw7dM1bSchsaw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, stable@kernel.org, Jann Horn , Christian Brauner Subject: [PATCH 5.15 87/87] filelock: Fix fcntl/close race recovery compat path Date: Thu, 25 Jul 2024 16:38:00 +0200 Message-ID: <20240725142741.717840717@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240725142738.422724252@linuxfoundation.org> References: <20240725142738.422724252@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jann Horn commit f8138f2ad2f745b9a1c696a05b749eabe44337ea upstream. When I wrote commit 3cad1bc01041 ("filelock: Remove locks reliably when fcntl/close race is detected"), I missed that there are two copies of the code I was patching: The normal version, and the version for 64-bit offsets on 32-bit kernels. Thanks to Greg KH for stumbling over this while doing the stable backport... Apply exactly the same fix to the compat path for 32-bit kernels. Fixes: c293621bbf67 ("[PATCH] stale POSIX lock handling") Cc: stable@kernel.org Link: https://bugs.chromium.org/p/project-zero/issues/detail?id=2563 Signed-off-by: Jann Horn Link: https://lore.kernel.org/r/20240723-fs-lock-recover-compatfix-v1-1-148096719529@google.com Signed-off-by: Christian Brauner Signed-off-by: Greg Kroah-Hartman --- fs/locks.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/fs/locks.c +++ b/fs/locks.c @@ -2605,8 +2605,9 @@ int fcntl_setlk64(unsigned int fd, struc error = do_lock_file_wait(filp, cmd, file_lock); /* - * Attempt to detect a close/fcntl race and recover by releasing the - * lock that was just acquired. There is no need to do that when we're + * Detect close/fcntl races and recover by zapping all POSIX locks + * associated with this file and our files_struct, just like on + * filp_flush(). There is no need to do that when we're * unlocking though, or for OFD locks. */ if (!error && file_lock->fl_type != F_UNLCK && @@ -2621,9 +2622,7 @@ int fcntl_setlk64(unsigned int fd, struc f = files_lookup_fd_locked(files, fd); spin_unlock(&files->file_lock); if (f != filp) { - file_lock->fl_type = F_UNLCK; - error = do_lock_file_wait(filp, cmd, file_lock); - WARN_ON_ONCE(error); + locks_remove_posix(filp, files); error = -EBADF; } }