From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 8CE2EF9F5 for ; Thu, 23 May 2024 18:07:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716487635; cv=none; b=MySpUPn5DvldQXf+73m5ws+fEjwd+57ZF2tdEXVJooi/pvSZCYfk5jwMUQNwyhqiFoFqTu5R14euRTgL/+a0qXr7QJMzJEOL7IFkuahG4P9rHYComXGrXc7pP+1fgVeatVTNyC2YMvjuA2n9EIM10lGrpb+pWSoeciICK60dzmw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716487635; c=relaxed/simple; bh=ze+uZvHoEac0gtM0EDXK7xa1oz4j4ce3yLzuoXrr7Xo=; h=From:In-Reply-To:References:To:Cc:Subject:MIME-Version: Content-Type:Date:Message-ID; b=s/mLW5bXQSIlBb11qigvu1F7klsVaT+aAJffl63MN+vSDYAZRLPKL0G5pSpLkTdxoXz/aXgRH2FDTE/tXA4i8wmXw65qzDnRfHR30k2ODijSHMC2ijDGCtDtg6fvTdcxupj4L/KytvONX1dJlbs2i7oQC3kErLzkbnLaWa1r1to= 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=TdfpYsEl; arc=none smtp.client-ip=170.10.129.124 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="TdfpYsEl" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1716487632; 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=KRDgVYqMRKVTVVPxWculCYevzyWeiQYRZji0ad67C1A=; b=TdfpYsEl5We4NSBzfv/3hfBp6Fhf5BP9gbirHhJMb9zQx8J+D8jZUVI4ahwvdIpWEAx3qm a6wC4kMq5xWTd4FdGs0gd8bLsskoO4m8qYPIfsiTQYkxVBO3148rj07FUaIt07UlDKs+5N jLYgrMLK/QzoqeUolvqPqzOgtz0Yq1w= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-643-fzIgdyQxMWqSuz_WYqEBOQ-1; Thu, 23 May 2024 14:07:08 -0400 X-MC-Unique: fzIgdyQxMWqSuz_WYqEBOQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5F1CB800169; Thu, 23 May 2024 18:07:07 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1DCD7C15BED; Thu, 23 May 2024 18:07:05 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <00000000000092914806191382ac@google.com> <580959.1716475058@warthog.procyon.org.uk> To: asmadeus@codewreck.org Cc: dhowells@redhat.com, syzbot , brauner@kernel.org, hdanton@sina.com, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] [v9fs?] KASAN: slab-use-after-free Read in p9_fid_destroy Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <641238.1716487625.1@warthog.procyon.org.uk> Date: Thu, 23 May 2024 19:07:05 +0100 Message-ID: <641239.1716487625@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 asmadeus@codewreck.org wrote: > > There's a problem in 9p's interaction with netfslib whereby a crash occurs > > because the 9p_fid structs get forcibly destroyed during client teardown > > (without paying attention to their refcounts) before netfslib has finished > > with them. However, it's not a simple case of deferring the clunking that > > p9_fid_put() does as that requires the client. > > "as that requires the client" doesn't parse "... as that requires the p9_client record to still be present."? David