From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Jakub Kicinski <kuba@kernel.org>,
syzbot+a1c743815982d9496393@syzkaller.appspotmail.com,
Anmol Karn <anmol.karan123@gmail.com>
Subject: [PATCH 5.4 06/39] rose: Fix Null pointer dereference in rose_send_frame()
Date: Sun, 6 Dec 2020 12:17:10 +0100 [thread overview]
Message-ID: <20201206111554.977320232@linuxfoundation.org> (raw)
In-Reply-To: <20201206111554.677764505@linuxfoundation.org>
From: Anmol Karn <anmol.karan123@gmail.com>
[ Upstream commit 3b3fd068c56e3fbea30090859216a368398e39bf ]
rose_send_frame() dereferences `neigh->dev` when called from
rose_transmit_clear_request(), and the first occurrence of the
`neigh` is in rose_loopback_timer() as `rose_loopback_neigh`,
and it is initialized in rose_add_loopback_neigh() as NULL.
i.e when `rose_loopback_neigh` used in rose_loopback_timer()
its `->dev` was still NULL and rose_loopback_timer() was calling
rose_rx_call_request() without checking for NULL.
- net/rose/rose_link.c
This bug seems to get triggered in this line:
rose_call = (ax25_address *)neigh->dev->dev_addr;
Fix it by adding NULL checking for `rose_loopback_neigh->dev`
in rose_loopback_timer().
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Reported-by: syzbot+a1c743815982d9496393@syzkaller.appspotmail.com
Tested-by: syzbot+a1c743815982d9496393@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=9d2a7ca8c7f2e4b682c97578dfa3f236258300b3
Signed-off-by: Anmol Karn <anmol.karan123@gmail.com>
Link: https://lore.kernel.org/r/20201119191043.28813-1-anmol.karan123@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/rose/rose_loopback.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)
--- a/net/rose/rose_loopback.c
+++ b/net/rose/rose_loopback.c
@@ -96,10 +96,19 @@ static void rose_loopback_timer(struct t
}
if (frametype == ROSE_CALL_REQUEST) {
- if ((dev = rose_dev_get(dest)) != NULL) {
- if (rose_rx_call_request(skb, dev, rose_loopback_neigh, lci_o) == 0)
- kfree_skb(skb);
- } else {
+ if (!rose_loopback_neigh->dev) {
+ kfree_skb(skb);
+ continue;
+ }
+
+ dev = rose_dev_get(dest);
+ if (!dev) {
+ kfree_skb(skb);
+ continue;
+ }
+
+ if (rose_rx_call_request(skb, dev, rose_loopback_neigh, lci_o) == 0) {
+ dev_put(dev);
kfree_skb(skb);
}
} else {
next prev parent reply other threads:[~2020-12-06 11:47 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-06 11:17 [PATCH 5.4 00/39] 5.4.82-rc1 review Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 01/39] devlink: Hold rtnl lock while reading netdev attributes Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 02/39] ipv6: addrlabel: fix possible memory leak in ip6addrlbl_net_init Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 03/39] net/af_iucv: set correct sk_protocol for child sockets Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 04/39] net/tls: missing received data after fast remote close Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 05/39] net/tls: Protect from calling tls_dev_del for TLS RX twice Greg Kroah-Hartman
2020-12-06 11:17 ` Greg Kroah-Hartman [this message]
2020-12-06 11:17 ` [PATCH 5.4 07/39] sock: set sk_err to ee_errno on dequeue from errq Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 08/39] tcp: Set INET_ECN_xmit configuration in tcp_reinit_congestion_control Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 09/39] tun: honor IOCB_NOWAIT flag Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 10/39] usbnet: ipheth: fix connectivity with iOS 14 Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 11/39] bonding: wait for sysfs kobject destruction before freeing struct slave Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 12/39] staging/octeon: fix up merge error Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 13/39] ima: extend boot_aggregate with kernel measurements Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 14/39] sched/fair: Fix unthrottle_cfs_rq() for leaf_cfs_rq list Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 15/39] netfilter: bridge: reset skb->pkt_type after NF_INET_POST_ROUTING traversal Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 16/39] ipv4: Fix tos mask in inet_rtm_getroute() Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 17/39] dt-bindings: net: correct interrupt flags in examples Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 18/39] chelsio/chtls: fix panic during unload reload chtls Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 19/39] ibmvnic: Ensure that SCRQ entry reads are correctly ordered Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 20/39] ibmvnic: Fix TX completion error handling Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 21/39] inet_ecn: Fix endianness of checksum update when setting ECT(1) Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 22/39] geneve: pull IP header before ECN decapsulation Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 23/39] net: ip6_gre: set dev->hard_header_len when using header_ops Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 24/39] net/x25: prevent a couple of overflows Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 25/39] cxgb3: fix error return code in t3_sge_alloc_qset() Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 26/39] net: pasemi: fix error return code in pasemi_mac_open() Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 27/39] vxlan: fix error return code in __vxlan_dev_create() Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 28/39] chelsio/chtls: fix a double free in chtls_setkey() Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 29/39] net: mvpp2: Fix error return code in mvpp2_open() Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 30/39] net: skbuff: ensure LSE is pullable before decrementing the MPLS ttl Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 31/39] net: openvswitch: ensure LSE is pullable before reading it Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 32/39] net/sched: act_mpls: " Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 33/39] net/mlx5: DR, Proper handling of unsupported Connect-X6DX SW steering Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 34/39] net/mlx5: Fix wrong address reclaim when command interface is down Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 35/39] ALSA: usb-audio: US16x08: fix value count for level meters Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 36/39] Input: xpad - support Ardwiino Controllers Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 37/39] Input: i8042 - add ByteSpeed touchpad to noloop table Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 38/39] tracing: Remove WARN_ON in start_thread() Greg Kroah-Hartman
2020-12-06 11:17 ` [PATCH 5.4 39/39] RDMA/i40iw: Address an mmap handler exploit in i40iw Greg Kroah-Hartman
2020-12-07 8:03 ` [PATCH 5.4 00/39] 5.4.82-rc1 review Naresh Kamboju
2020-12-07 15:55 ` Guenter Roeck
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