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 EA202199E9F; Thu, 25 Jul 2024 14:44:17 +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=1721918658; cv=none; b=R/nOEHdyv/rrKclCFt8BPrwgEYS35wzn6hAW3cpK9encK9kyJ0ldTA8Ul+P5fOiyFiJy4yqUhn/eUzzrJJgvsm/cc6MuEv7oZN8Ivuk4IRbQsQM95R2GEbSiI3TJda8FSBeQOKpUd4L0WqDXSyYpWHNuvfR00a/DJSOSVasCvkY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721918658; c=relaxed/simple; bh=woxgRUw1bBPya8jc/DEfpXZ2zYf7KUfhRmt1WPFiC1g=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GdSFnzqLoxSkC4fNW2AiG26UFavsoe6EFZXnmzv6+XzMYj2I3zvxN8BYkOKMXE2nMNP/MhaL/H+Drf9wRjePvcoyCwyQhsQ589/n+6kOB4XaslAY8xEN8FStEEpknT7Qm97TgBney258D/guYQivJSY2LWwYporE+Y4Dd206hRY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=wXpj9hyS; 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="wXpj9hyS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 943DAC116B1; Thu, 25 Jul 2024 14:44:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721918657; bh=woxgRUw1bBPya8jc/DEfpXZ2zYf7KUfhRmt1WPFiC1g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wXpj9hySz3SK52O5ofZTSHfuUWJjHWrcaDK7HnXJCb4MrSK3fI2nyI9PdPeKClL5r KVIjJFvSDbyn3C1QT2mhlpxEOPrjo4Ys7sxpjuh49DPgekAO4u4Q4VHTn43bDIubkE CDVv73+BHSevLKUwGrXihWTq/Frl6y9qoMKLQDg8= 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 5.4 43/43] filelock: Fix fcntl/close race recovery compat path Date: Thu, 25 Jul 2024 16:37:06 +0200 Message-ID: <20240725142732.097230811@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240725142730.471190017@linuxfoundation.org> References: <20240725142730.471190017@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-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 @@ -2656,8 +2656,9 @@ 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 && @@ -2671,9 +2672,7 @@ int fcntl_setlk64(unsigned int fd, struc f = fcheck(fd); spin_unlock(¤t->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, ¤t->files); error = -EBADF; } }