From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZov46Mt340/5Yeuyx8972C269d2EVZ/p5WLtWhe7/+R84li/b02NJT16My9nRfrDwHEJVn8 ARC-Seal: i=1; a=rsa-sha256; t=1526631453; cv=none; d=google.com; s=arc-20160816; b=SUa0qIqQ8asKAo9lbnG3Mb5THRuHsMQdsmrIdl9BycJcqW/45IhPAt/Nqaqqnwy4uk BZrWb7yGJqZV/dlQ8fMZ10csXK5o+uClQPkzVsWew4a6Elm57QK2dCMVVJdR5p2kzOpt BjdtHHfzS55VPBVvB17kTTz8uQBe6RvAQfbXVTJk9wGBuZ0+J363vBr2K0LBlZb2J+O9 0b66ltU40zpgKaqOwA6EG46yv3HvQfPQpVRqGCJsv5slM9LmAfer5sGROGER3XKmHkYi Y0yG2hVCa62m2mw2nHXBJk0+RQ7wZ42T/YA/+jsoNw95mUXDX/xJCELSAJ1/WKrD0yWs e9tA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature:arc-authentication-results; bh=V3P3FTlO8Oi4W363HPsrJoJAJlTdvSj4lWV7SBOz9uw=; b=xeRbEidYX5p6+sgIO2G3cbo7zp8EDhQMpSppN/TJJYp5CTORkzeCo/SRdigOoN8SGy hZv/txuy2hHjl4FJjgCGjPDi0to+2EdzyM+PTi+nUEgBkbTcccWn7NALrqh+xNJoucnq aPpwU4sskxD/H/vJmINfhaznZs5p2NVhWHhci/BmgHFJU4Mx9g2pVaxspx5YHlkiwGk5 cggYnbFaQTaOOwTgdYpdadSqI6QZX2ualy2ROOI6lL3qC7FXx5wO4nA0vsZcI2jcDMpt d9JmxK9lP3XUro0rGTSoxFKBXq/Tva2vElKxDptstFdREHUnomBp8E85L2ASZAHF0Y3H pb/g== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=tunxHFUN; spf=pass (google.com: domain of srs0=xuy6=if=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=XuY6=IF=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=tunxHFUN; spf=pass (google.com: domain of srs0=xuy6=if=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=XuY6=IF=linuxfoundation.org=gregkh@kernel.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+141d898c5f24489db4aa@syzkaller.appspotmail.com, Xin Long , Neil Horman , Marcelo Ricardo Leitner , "David S. Miller" Subject: [PATCH 4.16 26/55] sctp: remove sctp_chunk_put from fail_mark err path in sctp_ulpevent_make_rcvmsg Date: Fri, 18 May 2018 10:15:22 +0200 Message-Id: <20180518081458.753299529@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180518081457.428920292@linuxfoundation.org> References: <20180518081457.428920292@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1600789103167895925?= X-GMAIL-MSGID: =?utf-8?q?1600789103167895925?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long [ Upstream commit 6910e25de2257e2c82c7a2d126e3463cd8e50810 ] In Commit 1f45f78f8e51 ("sctp: allow GSO frags to access the chunk too"), it held the chunk in sctp_ulpevent_make_rcvmsg to access it safely later in recvmsg. However, it also added sctp_chunk_put in fail_mark err path, which is only triggered before holding the chunk. syzbot reported a use-after-free crash happened on this err path, where it shouldn't call sctp_chunk_put. This patch simply removes this call. Fixes: 1f45f78f8e51 ("sctp: allow GSO frags to access the chunk too") Reported-by: syzbot+141d898c5f24489db4aa@syzkaller.appspotmail.com Signed-off-by: Xin Long Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/ulpevent.c | 1 - 1 file changed, 1 deletion(-) --- a/net/sctp/ulpevent.c +++ b/net/sctp/ulpevent.c @@ -715,7 +715,6 @@ struct sctp_ulpevent *sctp_ulpevent_make return event; fail_mark: - sctp_chunk_put(chunk); kfree_skb(skb); fail: return NULL;