From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 5D17E1FF5E9 for ; Tue, 14 Jan 2025 20:40:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736887207; cv=none; b=aniDu5rNha8Ni0Q5TO3MlUVV5LLrhCGfw+cyDW9hKGGQPUenYOgIeO5a52grM1XQQGBsGOiSoiEliZbpEM1f3W9k5grMDIgL9VlUp6dDFq88hfNMeXgdlOZKIedQq1xvZtfT8pYTemnT3Waf/lKzxJrb5d14GYGWppYH09uV6xk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736887207; c=relaxed/simple; bh=iGtvFc/Jy4BJY0LRoDaVaXzDrDXFuoFF7wBMz6Gftpg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uStp75XrYAnKQwNWWuuE/4OBH4+YvGMYTVUl574qAIBgNZUtKJYnMX9/Q+1HXE4mAAMcLV3ksFY/Oo5GrcpjYoTMxyk1O2dZ8kxd4Kx7iDe54YWWtnOu7uXSWhR0L6k3305rb1bQfCl+UzhZRqmjWT77n5a7VHlMrkF9faJes7k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Fc78tHn9; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Fc78tHn9" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1736887205; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=iGtvFc/Jy4BJY0LRoDaVaXzDrDXFuoFF7wBMz6Gftpg=; b=Fc78tHn99GLhzsoZWYej40K6cIIaG46CzcMl+9xt1AVelq9aRt/Bb2J6cr0aj4rPtdNaWF tzu5zrH3K7l64HXiqHOfauHFDExcZMxDiSzwajETKXBfKJEJvQb/59EQytRdLYTW57/sLG dUi0cori0AwFtlecMs3KTG9aruZt9aw= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-614-8PfkFcqLMTezb9LkqFK0JQ-1; Tue, 14 Jan 2025 15:40:00 -0500 X-MC-Unique: 8PfkFcqLMTezb9LkqFK0JQ-1 X-Mimecast-MFC-AGG-ID: 8PfkFcqLMTezb9LkqFK0JQ Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id D77FD19560B3; Tue, 14 Jan 2025 20:39:56 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.226.88]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id EC0A919560AA; Tue, 14 Jan 2025 20:39:48 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Tue, 14 Jan 2025 21:39:31 +0100 (CET) Date: Tue, 14 Jan 2025 21:39:22 +0100 From: Oleg Nesterov To: Andrii Nakryiko Cc: Jiri Olsa , Aleksa Sarai , Eyal Birger , mhiramat@kernel.org, linux-kernel , linux-trace-kernel@vger.kernel.org, BPF-dev-list , Song Liu , Yonghong Song , John Fastabend , peterz@infradead.org, tglx@linutronix.de, bp@alien8.de, x86@kernel.org, linux-api@vger.kernel.org, Andrii Nakryiko , Daniel Borkmann , Alexei Starovoitov , "rostedt@goodmis.org" , rafi@rbk.io, Shmulik Ladkani Subject: Re: Crash when attaching uretprobes to processes running in Docker Message-ID: <20250114203922.GA5051@redhat.com> References: <20250110.152323-sassy.torch.lavish.rent-vKX3ul5B3qyi@cyphar.com> <20250114105802.GA19816@redhat.com> Precedence: bulk X-Mailing-List: linux-api@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 On 01/14, Andrii Nakryiko wrote: > > Should we just fix whoever is blocking kernel-internal special syscall > (sys_uretprobe)? Well, we can add __NR_uretprobe to mode1_syscalls[] but this won't really help. We can't "fix" the existing user-space setups which can nack any "unnecessary/unknown" syscall. > What would happen if someone blocked that other > special kernel-internal syscall for signal handling (can't remember > the name, sys_rt_sigreturn(). Yes, the task will crash after return from the signal handler if this syscall is filtered out. But, unlike sys_uretprobe(), sys_rt_sigreturn() is old, so the existing setups must know that sigreturn() should be respected... Oleg.