linux/net
Guillaume Nault 7901cd9796 ipmr: Fix skb headroom in ipmr_get_route().
In route.c, inet_rtm_getroute_build_skb() creates an skb with no
headroom. This skb is then used by inet_rtm_getroute() which may pass
it to rt_fill_info() and, from there, to ipmr_get_route(). The later
might try to reuse this skb by cloning it and prepending an IPv4
header. But since the original skb has no headroom, skb_push() triggers
skb_under_panic():

skbuff: skb_under_panic: text:00000000ca46ad8a len:80 put:20 head:00000000cd28494e data:000000009366fd6b tail:0x3c end:0xec0 dev:veth0
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:108!
invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 6 PID: 587 Comm: ip Not tainted 5.4.0-rc6+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014
RIP: 0010:skb_panic+0xbf/0xd0
Code: 41 a2 ff 8b 4b 70 4c 8b 4d d0 48 c7 c7 20 76 f5 8b 44 8b 45 bc 48 8b 55 c0 48 8b 75 c8 41 54 41 57 41 56 41 55 e8 75 dc 7a ff <0f> 0b 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00
RSP: 0018:ffff888059ddf0b0 EFLAGS: 00010286
RAX: 0000000000000086 RBX: ffff888060a315c0 RCX: ffffffff8abe4822
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88806c9a79cc
RBP: ffff888059ddf118 R08: ffffed100d9361b1 R09: ffffed100d9361b0
R10: ffff88805c68aee3 R11: ffffed100d9361b1 R12: ffff88805d218000
R13: ffff88805c689fec R14: 000000000000003c R15: 0000000000000ec0
FS:  00007f6af184b700(0000) GS:ffff88806c980000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc8204a000 CR3: 0000000057b40006 CR4: 0000000000360ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 skb_push+0x7e/0x80
 ipmr_get_route+0x459/0x6fa
 rt_fill_info+0x692/0x9f0
 inet_rtm_getroute+0xd26/0xf20
 rtnetlink_rcv_msg+0x45d/0x630
 netlink_rcv_skb+0x1a5/0x220
 rtnetlink_rcv+0x15/0x20
 netlink_unicast+0x305/0x3a0
 netlink_sendmsg+0x575/0x730
 sock_sendmsg+0xb5/0xc0
 ___sys_sendmsg+0x497/0x4f0
 __sys_sendmsg+0xcb/0x150
 __x64_sys_sendmsg+0x48/0x50
 do_syscall_64+0xd2/0xac0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Actually the original skb used to have enough headroom, but the
reserve_skb() call was lost with the introduction of
inet_rtm_getroute_build_skb() by commit 404eb77ea7 ("ipv4: support
sport, dport and ip_proto in RTM_GETROUTE").

We could reserve some headroom again in inet_rtm_getroute_build_skb(),
but this function shouldn't be responsible for handling the special
case of ipmr_get_route(). Let's handle that directly in
ipmr_get_route() by calling skb_realloc_headroom() instead of
skb_clone().

Fixes: 404eb77ea7 ("ipv4: support sport, dport and ip_proto in RTM_GETROUTE")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-16 13:06:54 -08:00
..
6lowpan 6lowpan: no need to check return value of debugfs_create functions 2019-07-06 12:50:01 +02:00
9p 9p pull request for inclusion in 5.4 2019-09-27 15:10:34 -07:00
802 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
8021q net: remove unnecessary variables and callback 2019-10-24 14:53:49 -07:00
appletalk appletalk: enforce CAP_NET_RAW for raw sockets 2019-09-24 16:37:18 +02:00
atm net: use skb_queue_empty_lockless() in poll() handlers 2019-10-28 13:33:41 -07:00
ax25 ax25: enforce CAP_NET_RAW for raw sockets 2019-09-24 16:37:18 +02:00
batman-adv Here are two batman-adv bugfixes: 2019-10-28 16:39:07 -07:00
bluetooth net: use skb_queue_empty_lockless() in poll() handlers 2019-10-28 13:33:41 -07:00
bpf bpf/flow_dissector: support flags in BPF_PROG_TEST_RUN 2019-07-25 18:00:41 -07:00
bpfilter Kbuild updates for v5.3 2019-07-12 16:03:16 -07:00
bridge bridge: ebtables: don't crash when using dnat target in output chains 2019-11-04 20:58:34 +01:00
caif net: use skb_queue_empty_lockless() in poll() handlers 2019-10-28 13:33:41 -07:00
can can: j1939: warn if resources are still linked on destroy 2019-11-13 10:42:34 +01:00
ceph libceph: use ceph_kvmalloc() for osdmap arrays 2019-09-16 12:06:25 +02:00
core devlink: Add method for time-stamp on reporter's dump 2019-11-11 16:04:21 -08:00
dcb
dccp dccp: do not leak jiffies on the wire 2019-11-04 11:36:31 -08:00
decnet net: use skb_queue_empty_lockless() in poll() handlers 2019-10-28 13:33:41 -07:00
dns_resolver Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs" 2019-07-10 18:43:43 -07:00
dsa net: dsa: tag_8021q: Fix dsa_8021q_restore_pvid for an absent pvid 2019-11-16 12:23:53 -08:00
ethernet
hsr hsr: switch ->dellink() to ->ndo_uninit() 2019-07-11 14:37:45 -07:00
ieee802154 net: core: add generic lockdep keys 2019-10-24 14:53:48 -07:00
ife net: Fix Kconfig indentation 2019-09-26 08:56:17 +02:00
ipv4 ipmr: Fix skb headroom in ipmr_get_route(). 2019-11-16 13:06:54 -08:00
ipv6 seg6: fix skb transport_header after decap_and_validate() 2019-11-16 12:18:32 -08:00
iucv net/af_iucv: mark expected switch fall-throughs 2019-07-29 10:26:14 -07:00
kcm kcm: disable preemption in kcm_parse_func_strparser() 2019-09-27 10:27:14 +02:00
key Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-07-08 19:48:57 -07:00
l2tp net: core: add generic lockdep keys 2019-10-24 14:53:48 -07:00
l3mdev ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREF 2019-06-23 13:24:17 -07:00
lapb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 20:20:36 -07:00
llc net: silence KCSAN warnings around sk_add_backlog() calls 2019-10-09 21:42:59 -07:00
mac80211 mac80211: fix station inactive_time shortly after boot 2019-11-08 09:17:28 +01:00
mac802154
mpls ipv4: mpls: fix mpls_xmit for iptunnel 2019-08-25 14:34:08 -07:00
ncsi net/ncsi: Disable global multicast filter 2019-09-19 18:04:40 -07:00
netfilter Merge branch 'master' of git://blackhole.kfki.hu/nf 2019-11-04 20:59:00 +01:00
netlabel netlabel: remove redundant assignment to pointer iter 2019-09-01 11:45:02 -07:00
netlink net: remove empty netlink_tap_exit_net 2019-06-14 19:50:33 -07:00
netrom net: core: add generic lockdep keys 2019-10-24 14:53:48 -07:00
nfc nfc: netlink: fix double device reference drop 2019-11-07 15:23:19 -08:00
nsh treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
openvswitch netns: fix GFP flags in rtnl_net_notifyid() 2019-10-25 20:14:42 -07:00
packet netfilter: drop bridge nf reset from nf_reset 2019-10-01 18:42:15 +02:00
phonet net: use skb_queue_empty_lockless() in poll() handlers 2019-10-28 13:33:41 -07:00
psample net: sched: take reference to psample group in flow_action infra 2019-09-16 09:18:03 +02:00
qrtr net: qrtr: Stop rx_worker before freeing node 2019-09-21 18:45:46 -07:00
rds rds: ib: update WR sizes when bringing up connection 2019-11-16 12:59:08 -08:00
rfkill treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
rose net: core: add generic lockdep keys 2019-10-24 14:53:48 -07:00
rxrpc rxrpc: Fix handling of last subpacket of jumbo packet 2019-10-31 12:23:09 -07:00
sched net: sched: prevent duplicate flower rules from tcf_proto destroy race 2019-11-05 17:47:26 -08:00
sctp inet: stop leaking jiffies on the wire 2019-11-01 14:57:52 -07:00
smc net/smc: fix fastopen for non-blocking connect() 2019-11-16 13:03:33 -08:00
strparser Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
sunrpc SUNRPC: Destroy the back channel when we destroy the host transport 2019-10-30 12:04:35 -04:00
switchdev
tipc tipc: add back tipc prefix to log messages 2019-11-14 18:03:03 -08:00
tls net/tls: add a TX lock 2019-11-06 17:33:32 -08:00
unix net: use skb_queue_empty_lockless() in poll() handlers 2019-10-28 13:33:41 -07:00
vmw_vsock vsock/virtio: fix sock refcnt holding during the shutdown 2019-11-08 12:17:50 -08:00
wimax wimax: no need to check return value of debugfs_create functions 2019-08-10 15:25:47 -07:00
wireless nl80211: fix validation of mesh path nexthop 2019-10-30 10:11:18 +01:00
x25 net: silence KCSAN warnings around sk_add_backlog() calls 2019-10-09 21:42:59 -07:00
xdp xsk: Fix registration of Rx-only sockets 2019-10-23 20:22:11 -07:00
xfrm xfrm: release device reference for invalid state 2019-11-12 08:24:38 +01:00
compat.c
Kconfig devlink: Add packet trap infrastructure 2019-08-17 12:40:08 -07:00
Makefile
socket.c Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-07-19 10:42:02 -07:00
sysctl_net.c