linux/net
Davide Caratti 31fe34a011 net/sched: sch_frag: fix stack OOB read while fragmenting IPv4 packets
when 'act_mirred' tries to fragment IPv4 packets that had been previously
re-assembled using 'act_ct', splats like the following can be observed on
kernels built with KASAN:

 BUG: KASAN: stack-out-of-bounds in ip_do_fragment+0x1b03/0x1f60
 Read of size 1 at addr ffff888147009574 by task ping/947

 CPU: 0 PID: 947 Comm: ping Not tainted 5.12.0-rc6+ #418
 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
 Call Trace:
  <IRQ>
  dump_stack+0x92/0xc1
  print_address_description.constprop.7+0x1a/0x150
  kasan_report.cold.13+0x7f/0x111
  ip_do_fragment+0x1b03/0x1f60
  sch_fragment+0x4bf/0xe40
  tcf_mirred_act+0xc3d/0x11a0 [act_mirred]
  tcf_action_exec+0x104/0x3e0
  fl_classify+0x49a/0x5e0 [cls_flower]
  tcf_classify_ingress+0x18a/0x820
  __netif_receive_skb_core+0xae7/0x3340
  __netif_receive_skb_one_core+0xb6/0x1b0
  process_backlog+0x1ef/0x6c0
  __napi_poll+0xaa/0x500
  net_rx_action+0x702/0xac0
  __do_softirq+0x1e4/0x97f
  do_softirq+0x71/0x90
  </IRQ>
  __local_bh_enable_ip+0xdb/0xf0
  ip_finish_output2+0x760/0x2120
  ip_do_fragment+0x15a5/0x1f60
  __ip_finish_output+0x4c2/0xea0
  ip_output+0x1ca/0x4d0
  ip_send_skb+0x37/0xa0
  raw_sendmsg+0x1c4b/0x2d00
  sock_sendmsg+0xdb/0x110
  __sys_sendto+0x1d7/0x2b0
  __x64_sys_sendto+0xdd/0x1b0
  do_syscall_64+0x33/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7f82e13853eb
 Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 f3 0f 1e fa 48 8d 05 75 42 2c 00 41 89 ca 8b 00 85 c0 75 14 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 75 c3 0f 1f 40 00 41 57 4d 89 c7 41 56 41 89
 RSP: 002b:00007ffe01fad888 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
 RAX: ffffffffffffffda RBX: 00005571aac13700 RCX: 00007f82e13853eb
 RDX: 0000000000002330 RSI: 00005571aac13700 RDI: 0000000000000003
 RBP: 0000000000002330 R08: 00005571aac10500 R09: 0000000000000010
 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe01faefb0
 R13: 00007ffe01fad890 R14: 00007ffe01fad980 R15: 00005571aac0f0a0

 The buggy address belongs to the page:
 page:000000001dff2e03 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x147009
 flags: 0x17ffffc0001000(reserved)
 raw: 0017ffffc0001000 ffffea00051c0248 ffffea00051c0248 0000000000000000
 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 Memory state around the buggy address:
  ffff888147009400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff888147009480: f1 f1 f1 f1 04 f2 f2 f2 f2 f2 f2 f2 00 00 00 00
 >ffff888147009500: 00 00 00 00 00 00 00 00 00 00 f2 f2 f2 f2 f2 f2
                                                              ^
  ffff888147009580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff888147009600: 00 00 00 00 00 00 00 00 00 00 00 00 00 f2 f2 f2

for IPv4 packets, sch_fragment() uses a temporary struct dst_entry. Then,
in the following call graph:

  ip_do_fragment()
    ip_skb_dst_mtu()
      ip_dst_mtu_maybe_forward()
        ip_mtu_locked()

the pointer to struct dst_entry is used as pointer to struct rtable: this
turns the access to struct members like rt_mtu_locked into an OOB read in
the stack. Fix this changing the temporary variable used for IPv4 packets
in sch_fragment(), similarly to what is done for IPv6 few lines below.

Fixes: c129412f74 ("net/sched: sch_frag: add generic packet fragment support.")
Cc: <stable@vger.kernel.org> # 5.11
Reported-by: Shuang Li <shuali@redhat.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-29 15:31:53 -07:00
..
6lowpan 6lowpan: Fix some typos in nhc_udp.c 2021-03-24 17:52:11 -07:00
9p net: 9p: Correct function names in the kerneldoc comments 2021-03-28 17:56:56 -07:00
802
8021q Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-04-26 12:00:00 -07:00
appletalk appletalk: Fix skb allocation size in loopback case 2021-02-12 16:40:28 -08:00
atm net: atm: pppoatm: use new API for wakeup tasklet 2021-01-29 18:24:05 -08:00
ax25 net/ax25: Delete obsolete TODO file 2021-03-30 16:54:50 -07:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-04-09 20:48:35 -07:00
bluetooth Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
bpf bpf: selftests: Add kfunc_call test 2021-03-26 20:41:52 -07:00
bpfilter net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
bridge net: bridge: mcast: fix broken length + header check for MRDv6 Adv. 2021-04-27 14:02:06 -07:00
caif net: caif: Use netif_rx_any_context(). 2021-02-15 13:21:48 -08:00
can can: proc: fix rcvlist_* header alignment on 64-bit system 2021-04-25 19:43:00 +02:00
ceph net: ceph: Fix a typo in osdmap.c 2021-03-25 17:05:07 -07:00
core Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
dcb net: dcb: use obj-$(CONFIG_DCB) form in net/Makefile 2021-01-27 17:03:52 -08:00
dccp net: dccp: use net_generic storage 2021-04-09 16:34:56 -07:00
decnet net/decnet: Delete obsolete TODO file 2021-03-30 16:54:50 -07:00
dns_resolver net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
dsa net: selftest: fix build issue if INET is disabled 2021-04-28 14:06:45 -07:00
ethernet of: net: pass the dst buffer to of_get_mac_address() 2021-04-13 14:35:02 -07:00
ethtool ethtool: stats: clarify the initialization to ETHTOOL_STAT_NOT_SET 2021-04-19 16:23:32 -07:00
hsr Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-04-09 20:48:35 -07:00
ieee802154 net: remove the new_ifindex argument from dev_change_net_namespace 2021-04-07 14:43:28 -07:00
ife net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
ipv4 icmp: standardize naming of RFC 8335 PROBE constants 2021-04-28 13:42:23 -07:00
ipv6 seg6: add counters support for SRv6 Behaviors 2021-04-29 15:26:57 -07:00
iucv iucv: af_iucv.c: Couple of typo fixes 2021-03-28 17:31:13 -07:00
kcm kcm: kcmsock.c: Couple of typo fixes 2021-03-28 17:31:13 -07:00
key
l2tp net: fix a concurrency bug in l2tp_tunnel_register() 2021-04-27 14:23:13 -07:00
l3mdev l3mdev: Correct function names in the kerneldoc comments 2021-03-28 17:56:55 -07:00
lapb net: lapb: Make "lapb_t1timer_running" able to detect an already running timer 2021-03-23 14:14:50 -07:00
llc llc2: Remove redundant assignment to rc 2021-04-27 14:16:14 -07:00
mac80211 Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
mac802154 net: mac802154: Fix general protection fault 2021-04-06 22:42:16 +02:00
mpls mpls: Remove redundant assignment to err 2021-04-27 14:17:00 -07:00
mptcp Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-04-26 12:00:00 -07:00
ncsi Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-04-09 20:48:35 -07:00
netfilter netfilter: nft_socket: fix build with CONFIG_SOCK_CGROUP_DATA=n 2021-04-27 22:34:05 +02:00
netlabel Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
netlink netlink: don't call ->netlink_bind with table lock held 2021-04-16 17:01:04 -07:00
netrom net: netrom: nr_in: Remove redundant assignment to ns 2021-04-28 13:59:08 -07:00
nfc Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
nsh
openvswitch openvswitch: fix stack OOB read while fragmenting IPv4 packets 2021-04-29 15:31:53 -07:00
packet net/packet: remove data races in fanout operations 2021-04-14 14:34:38 -07:00
phonet
psample psample: Add additional metadata attributes 2021-03-14 15:00:43 -07:00
qrtr Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-04-26 12:00:00 -07:00
rds Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
rfkill Another set of updates, all over the map: 2021-04-20 16:44:04 -07:00
rose net: rose: Fix fall-through warnings for Clang 2021-03-10 12:45:15 -08:00
rxrpc Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
sched net/sched: sch_frag: fix stack OOB read while fragmenting IPv4 packets 2021-04-29 15:31:53 -07:00
sctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-04-17 11:08:07 -07:00
smc net/smc: Remove redundant assignment to rc 2021-04-27 14:17:50 -07:00
strparser
sunrpc sunrpc: Remove unused function ip_map_lookup 2021-04-06 11:24:31 -04:00
switchdev net: bridge: propagate extack through switchdev_port_attr_set 2021-02-14 17:38:11 -08:00
tipc Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
tls net/tls: Remove redundant initialization of record 2021-04-27 14:15:19 -07:00
unix af_unix: handle idmapped mounts 2021-01-24 14:27:18 +01:00
vmw_vsock Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-04-26 12:00:00 -07:00
wireless Networking changes for 5.13. 2021-04-29 11:57:23 -07:00
x25 af_x25.c: Fix a spello 2021-03-28 17:31:13 -07:00
xdp xsk: Align XDP socket batch size with DPDK 2021-04-23 09:50:35 +02:00
xfrm xfrm: ipcomp: remove unnecessary get_cpu() 2021-04-19 12:49:29 +02:00
compat.c
devres.c
Kconfig net: selftest: fix build issue if INET is disabled 2021-04-28 14:06:45 -07:00
Makefile net: l3mdev: use obj-$(CONFIG_NET_L3_MASTER_DEV) form in net/Makefile 2021-01-27 17:03:52 -08:00
socket.c net: Fix a misspell in socket.c 2021-03-25 16:56:27 -07:00
sysctl_net.c net: Ensure net namespace isolation of sysctls 2021-04-12 13:27:11 -07:00