From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZqckcoENv+7/MztsHmEnIORqasBXEyF0ngi1W9QzvNytDUeWeeLWp7t43CQ3j3Bn3OR1DJv ARC-Seal: i=1; a=rsa-sha256; t=1526631670; cv=none; d=google.com; s=arc-20160816; b=ggGNrwWd9++gJbeSltloxTLIoQaqX9t1p4dVL6M6kvptV2S9dm6usjl+6Ipk7c1oLC teO4fpnMG9zpsyQBwohzCjH6s7KlEFQ15MZ9RN8lB4BsdC3f6D5TXL2AfFC+lHVe4ZHT layoQexe9XgxNFtIOXsFH/z8umfsjUXcZHau3OFozDQ8DJntY0U/shJUnRBIhAn6ht90 DB26NFy48auyBaQwnPusgABNNfYs9FwoKqegGi67GIb8SoNqu/01/hSctdVMKorNgPM4 am660JwQEqY2Uw0yWjNAclapuv2oPZvyOfoCRNdD4ykacz071FC5u2wFZ7JS/Ol7o/uz aqYQ== 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=QVI/hOX8OoKsUP+gtUZrP6MixWhGsPGE4DmdA0mSPuQ=; b=UMtGY5kQNJsG3F6DrP+hPmI13OBkFG9c5PHISF0RLDCL+Og/jkjqB7EJpqC+gG8WLA RoOCPvPcLD3yxwDAOw5yBU45X6uZclG4LGWjQE7r8SQ6U5BC/cdnYvI4DU70xBga4G9S MfQ/mqg6XSZb2l/yX/9ZA+WLmwRfQ/6pH89JAb9O8WK7/+NxLtGVEN0fajDfoD7AlKY0 YQeaWqHAY18lh2YxyWf+QWdoYP4S3CE/U+op8+9T/ColrQaQVbBsUiMQVacXoDm9eb0t jCjLT8cf7d8X4XXRuMux8jHv8K7vK0K1QQ3xCE63NZn7zsorAM+Ow269R46dkL6m0STD Z98w== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=NfbUJtK6; 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=NfbUJtK6; 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 4.14 25/45] sctp: remove sctp_chunk_put from fail_mark err path in sctp_ulpevent_make_rcvmsg Date: Fri, 18 May 2018 10:15:42 +0200 Message-Id: <20180518081531.619661054@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180518081530.331586165@linuxfoundation.org> References: <20180518081530.331586165@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?1600789330229525800?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.14-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 @@ -717,7 +717,6 @@ struct sctp_ulpevent *sctp_ulpevent_make return event; fail_mark: - sctp_chunk_put(chunk); kfree_skb(skb); fail: return NULL;