From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) (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 EBEB21E47A3; Thu, 9 Oct 2025 14:06:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760018771; cv=none; b=Vc+vlR7JJzwaFtKK9D3DIq4wInKyHW0dP3dG9IDr745m3UWhiRasSCgxc3pmbSTdoxDVD0NU7jsSny70xw7fivs7ENOWXev6f36FKrf0MABmr19iaEPU/YNbsMPbrnENd1b+te0OeS4Wc5mI1bIBGNoZY+VVXVWYIgvPODbnZi4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760018771; c=relaxed/simple; bh=wpi1WDWENZNucIqzTCYS/kpzZuHNHMw9EDbF6qY427Q=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Z80siXNDXnVG4EtcZtYEMkdureR3AYdSqy0I6Zidu4c5fXk5wW8Mdgw4Ia25biFTvJTPZZ/ulXiPvuCqHvp0pKX5v4+A0jfYS6xX67D2vjwOTGtVWgZpOeHuQfnA6D0GZyePme1JnoJG23h3F4s2R+89eGlsv97Iz0jtNRNYEWI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 28C79BBCAB; Thu, 9 Oct 2025 13:57:47 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf18.hostedemail.com (Postfix) with ESMTPA id 123242F; Thu, 9 Oct 2025 13:57:44 +0000 (UTC) Date: Thu, 9 Oct 2025 09:57:44 -0400 From: Steven Rostedt To: Ankit Khushwaha Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, david.hunter.linux@gmail.com, skhan@linuxfoundation.org, linux-kernel-mentees@lists.linuxfoundation.org, Masami Hiramatsu , Mathieu Desnoyers , syzbot+ddc001b92c083dbf2b97@syzkaller.appspotmail.com Subject: Re: [PATCH v3] ring buffer: Propagate __rb_map_vma return value to caller Message-ID: <20251009095744.443db14b@gandalf.local.home> In-Reply-To: <20251009045345.8954-1-ankitkhushwaha.linux@gmail.com> References: <20251009045345.8954-1-ankitkhushwaha.linux@gmail.com> X-Mailer: Claws Mail 3.20.0git84 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: u7ee89ea1wegxtoyhbphbqe3qeqipj3o X-Rspamd-Server: rspamout07 X-Rspamd-Queue-Id: 123242F X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX19ssnBb5s9lqxsepWuLpsIvqanHttfzsvU= X-HE-Tag: 1760018264-251375 X-HE-Meta: U2FsdGVkX18Iw/henf7Qo2umn/CAr5c/XzkBiySzpEon0NEVoVIG5vW+tIUP2E4naPJaGrdpDZZZc+QEK607BVrPoWnJ1tsizgiBrol4D9iKFjxm+KhnJckJjKbKg3huYYOFjHyYJi1dJNhDcV2859S/N0yXYHMESZ/yU+0a9e+fP7G1Eynz/+9ALZJJBdsnS0eXx9Ig5AyV5BqEqaICqfMx+mBakqj6EDorJcrD61Fr2V8EvdMQd+HtyjG+JMrxzsWRX+sqnSiYJZuMyA3DdMrdR56WwY1WlcpEMh2WMuFUNU86xP0PJodahadKnrz9iL+izF1n5H5sEQN0FmwCEbEBEF/WfSffW/OdoihDCZ5bCecxE/EZjbZN+y30jI83mVAhTRVPREaeSIGtCKZjpBU9E13ywhu6VsGC85m3Zt0hlRc21XMjvpppPBr4q6eG6AVeyx4dEWv93wqWGkJK/JymgKP6nRIqOSBaEqLKs9o= On Thu, 9 Oct 2025 10:23:45 +0530 Ankit Khushwaha wrote: > The return value from __rb_map_vma(), which rejects writable or > executable mappings (VM_WRITE, VM_EXEC, or !VM_MAYSHARE), was being > ignored. As a result the caller of `__rb_map_vma` always returned 0 even when the > mapping had actually failed, allowing it to proceed with an invalid VMA. > > Reported-by: syzbot+ddc001b92c083dbf2b97@syzkaller.appspotmail.com > Closes: https://syzkaller.appspot.com/bug?id=194151be8eaebd826005329b2e123aecae714bdb > Signed-off-by: Ankit Khushwaha > --- > > Changes in v3: https://lore.kernel.org/linux-trace-kernel/20251008172516.20697-1-ankitkhushwaha.linux@gmail.com/ > * Same as v2:) > > Changes in v2: https://lore.kernel.org/linux-trace-kernel/20251007171256.20884-1-ankitkhushwaha.linux@gmail.com/ > * applied minor cleanup suggested by Steve in v1 > This is good practice, but I already pulled in v2. -- Steve > --- > kernel/trace/ring_buffer.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c > index 43460949ad3f..1244d2c5c384 100644 > --- a/kernel/trace/ring_buffer.c > +++ b/kernel/trace/ring_buffer.c > @@ -7273,7 +7273,7 @@ int ring_buffer_map(struct trace_buffer *buffer, int cpu, > atomic_dec(&cpu_buffer->resize_disabled); > } > > - return 0; > + return err; > } > > int ring_buffer_unmap(struct trace_buffer *buffer, int cpu)