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 E51E2199B8 for ; Wed, 6 Mar 2024 21:08:14 +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=1709759295; cv=none; b=VZ0ab/1O4wpTVXXwgNYR5lgqi3WpQ/nrpbSG5ngFq/b4tE/q8OFjrr6DHOGJAsPf1cGb1MesJBMeh+qmQd789TWkskPoJruOv1ea0r+h9V1m3z6jfg0TwHNJfA+zfzT/xvo2hq/UjXCiuFxW9KF5QfQiSeQaPSL+VvTMXsKQlUk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709759295; c=relaxed/simple; bh=EzlP/tNlT9end5rv/+e0l1sPMFrXfcchMFj0sd+HffU=; h=Date:To:From:Subject:Message-Id; b=nfN2lIHfJPiTVG5XqyqMop0Rk1vx0cRrybO+dzN4FwlJt1KzXk9wXBGSdwLh8Am36+YHz1XP7N4DrYV0tZjgSfycsDgQQNvoWSJUSumlZHTnbuCxJ02FElplvDuwFID3YujgFCKR96eZ70LQQ7HPBGKJt34SZCK01n1Ua7o408I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=uHUQ9k01; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="uHUQ9k01" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 78BC9C433F1; Wed, 6 Mar 2024 21:08:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1709759294; bh=EzlP/tNlT9end5rv/+e0l1sPMFrXfcchMFj0sd+HffU=; h=Date:To:From:Subject:From; b=uHUQ9k01AS2XXEH2+J2pT+jWxf1Ox7eDLnu+Uta2rAd4mJf1J2y4Au/UDJ2B1/QCu DCpdk4dit+TMo4nRWuGi58ngtLthHZCZ9QG8wpQFSItd/4yCMHpE2YRM9kPCPIFf3L cXGpv52AD18lbzPHOyivQP9kB/GKOfXEauEdbr48= Date: Wed, 06 Mar 2024 13:08:13 -0800 To: mm-commits@vger.kernel.org,wenyang.linux@foxmail.com,pcc@google.com,ebiederm@xmission.com,brauner@kernel.org,oleg@redhat.com,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-nonmm-stable] get_signal-hide_si_addr_tag_bits-fix-the-usage-of-uninitialized-ksig.patch removed from -mm tree Message-Id: <20240306210814.78BC9C433F1@smtp.kernel.org> Precedence: bulk X-Mailing-List: mm-commits@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig has been removed from the -mm tree. Its filename was get_signal-hide_si_addr_tag_bits-fix-the-usage-of-uninitialized-ksig.patch This patch was dropped because it was merged into the mm-nonmm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: Oleg Nesterov Subject: get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig Date: Mon, 26 Feb 2024 17:56:50 +0100 ksig->ka and ksig->info are not initialized if get_signal() returns 0 or if the caller is PF_USER_WORKER. Check signr != 0 before SA_EXPOSE_TAGBITS and move the "out" label down. The latter means that ksig->sig won't be initialized if a PF_USER_WORKER thread gets a fatal signal but this is fine, PF_USER_WORKER's don't use ksig. And there is nothing new, in this case ksig->ka and ksig-info are not initialized anyway. Add a comment. Link: https://lkml.kernel.org/r/20240226165650.GA20829@redhat.com Signed-off-by: Oleg Nesterov Cc: Christian Brauner Cc: Eric W. Biederman Cc: Peter Collingbourne Cc: Wen Yang Signed-off-by: Andrew Morton --- kernel/signal.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/kernel/signal.c~get_signal-hide_si_addr_tag_bits-fix-the-usage-of-uninitialized-ksig +++ a/kernel/signal.c @@ -2881,8 +2881,9 @@ relock: /* * PF_USER_WORKER threads will catch and exit on fatal signals - * themselves. They have cleanup that must be performed, so - * we cannot call do_exit() on their behalf. + * themselves. They have cleanup that must be performed, so we + * cannot call do_exit() on their behalf. Note that ksig won't + * be properly initialized, PF_USER_WORKER's shouldn't use it. */ if (current->flags & PF_USER_WORKER) goto out; @@ -2894,12 +2895,12 @@ relock: /* NOTREACHED */ } spin_unlock_irq(&sighand->siglock); -out: + ksig->sig = signr; - if (!(ksig->ka.sa.sa_flags & SA_EXPOSE_TAGBITS)) + if (signr && !(ksig->ka.sa.sa_flags & SA_EXPOSE_TAGBITS)) hide_si_addr_tag_bits(ksig); - +out: return signr > 0; } _ Patches currently in -mm which might be from oleg@redhat.com are