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 6E94619D89C; Thu, 25 Jul 2024 14:41:54 +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=1721918514; cv=none; b=lXiAwBjCwYWuQX/qFuhrQZy1tLntgw9M9QRmbxi8NA4Bb03C+OD150tgrrKuxa//BA2pMccMmGAQ5UdV+Yl0FdBEttLZyL4k+PWm8SdBO966AK+O3v96CPp/UUprtqFHHDW6UZfvsDcgpzqi2LwUvaS5RIYQ+aKeRsBZUR1RnCE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721918514; c=relaxed/simple; bh=J0/dNcvsU9UHX8tfoFHNKTipjg+JHlIG7R3/cg4UJ9E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gxTc+wHGgG2LypNg0j7gQWJWIXv83fQTwBiYAMUHImcVQCUm87lqfefTRh4zqGunPdhk1Q46oLHu/ITnxf24inabIDP6wKf+Xq1jYA57GdFo4oiV+/dHqCvhsH8hKthu8L7Ktbg9F57aTYT+btdUVRNuKbHzef+8E1+0zF1K2AU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BHxFKzGg; 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="BHxFKzGg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D27E8C32782; Thu, 25 Jul 2024 14:41:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721918514; bh=J0/dNcvsU9UHX8tfoFHNKTipjg+JHlIG7R3/cg4UJ9E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BHxFKzGgX4fAprcqKwdV9VQ5pEj4sNygSlO3qAg+1SkEHh9nXN9hbQa8flih9/wVX oulgCTltS5x9XqZNZBBUJ7QDxZm81y7/dTXIHLXllcbH1oM6/PF+AAxyooo6DBX96m nTESE+vvVZlTllrqNfPrm0f81HWjP/MsnsaEE1iA= 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 4.19 33/33] filelock: Fix fcntl/close race recovery compat path Date: Thu, 25 Jul 2024 16:36:56 +0200 Message-ID: <20240725142729.759663258@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240725142728.511303502@linuxfoundation.org> References: <20240725142728.511303502@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 4.19-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 @@ -2427,8 +2427,9 @@ 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 && @@ -2442,9 +2443,7 @@ 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; } }