linux/net/core
Eric Dumazet 06a22d897d bpf: fix access to skb_shared_info->gso_segs
It is possible we reach bpf_convert_ctx_access() with
si->dst_reg == si->src_reg

Therefore, we need to load BPF_REG_AX before eventually
mangling si->src_reg.

syzbot generated this x86 code :
   3:   55                      push   %rbp
   4:   48 89 e5                mov    %rsp,%rbp
   7:   48 81 ec 00 00 00 00    sub    $0x0,%rsp // Might be avoided ?
   e:   53                      push   %rbx
   f:   41 55                   push   %r13
  11:   41 56                   push   %r14
  13:   41 57                   push   %r15
  15:   6a 00                   pushq  $0x0
  17:   31 c0                   xor    %eax,%eax
  19:   48 8b bf c0 00 00 00    mov    0xc0(%rdi),%rdi
  20:   44 8b 97 bc 00 00 00    mov    0xbc(%rdi),%r10d
  27:   4c 01 d7                add    %r10,%rdi
  2a:   48 0f b7 7f 06          movzwq 0x6(%rdi),%rdi // Crash
  2f:   5b                      pop    %rbx
  30:   41 5f                   pop    %r15
  32:   41 5e                   pop    %r14
  34:   41 5d                   pop    %r13
  36:   5b                      pop    %rbx
  37:   c9                      leaveq
  38:   c3                      retq

Fixes: d9ff286a0f ("bpf: allow BPF programs access skb_shared_info->gso_segs field")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-07-23 14:12:37 -07:00
..
bpf_sk_storage.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 20:20:36 -07:00
datagram.c datagram: remove rendundant 'peeked' argument 2019-04-08 09:51:54 -07:00
datagram.h net/core: Allow the compiler to verify declaration and definition consistency 2019-03-27 13:49:44 -07:00
dev_addr_lists.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
dev_ioctl.c net/core: Document all dev_ioctl() arguments 2019-03-27 13:49:43 -07:00
dev.c skbuff: increase verbosity when dumping skb data 2019-07-08 19:38:46 -07:00
devlink.c devlink: Introduce PCI VF port flavour and port attribute 2019-07-09 12:02:13 -07:00
drop_monitor.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
dst_cache.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
dst.c blackhole_netdev: use blackhole_netdev to invalidate dst entries 2019-07-01 19:34:46 -07:00
ethtool.c net: ethtool: Allow parsing ETHER_FLOW types when using flow_rule 2019-06-27 09:38:17 -07:00
failover.c failover: allow name change on IFF_UP slave interfaces 2019-04-10 22:12:26 -07:00
fib_notifier.c
fib_rules.c SPDX update for 5.2-rc4 2019-06-08 12:52:42 -07:00
filter.c bpf: fix access to skb_shared_info->gso_segs 2019-07-23 14:12:37 -07:00
flow_dissector.c net/flow_dissector: add connection tracking dissection 2019-07-09 12:11:59 -07:00
flow_offload.c net: flow_offload: add flow_block_cb_is_busy() and use it 2019-07-09 14:38:50 -07:00
gen_estimator.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
gen_stats.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
gro_cells.c gro_cells: make sure device is up in gro_cells_receive() 2019-03-10 11:07:14 -07:00
hwbm.c net: hwbm: Make the hwbm_pool lock a mutex 2019-06-09 19:40:10 -07:00
link_watch.c net: link_watch: prevent starvation when processing linkwatch wq 2019-07-01 19:02:47 -07:00
lwt_bpf.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295 2019-06-05 17:36:38 +02:00
lwtunnel.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
Makefile bpf: Introduce bpf sk local storage 2019-04-27 09:07:04 -07:00
neighbour.c net: neigh: fix multiple neigh timer scheduling 2019-07-15 11:03:29 -07:00
net_namespace.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2019-07-11 10:55:49 -07:00
net-procfs.c treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
net-sysfs.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
net-sysfs.h
net-traces.c page_pool: add tracepoints for page_pool with details need by XDP 2019-06-19 11:23:13 -04:00
netclassid_cgroup.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
netevent.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
netpoll.c net: ipv4: provide __rcu annotation for ifa_list 2019-06-02 18:08:36 -07:00
netprio_cgroup.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
page_pool.c net: core: page_pool: add user refcnt and reintroduce page_pool_destroy 2019-07-08 14:58:04 -07:00
pktgen.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-07 11:00:14 -07:00
ptp_classifier.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295 2019-06-05 17:36:38 +02:00
request_sock.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
rtnetlink.c rtnetlink: skip metrics loop for dst_default_metrics 2019-06-26 13:14:59 -07:00
scm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
secure_seq.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
skbuff.c skbuff: fix compilation warnings in skb_dump() 2019-07-16 14:12:06 -07:00
skmsg.c bpf: sockmap/tls, close can race with map free 2019-07-22 16:04:17 +02:00
sock_diag.c
sock_map.c bpf: sockmap, only create entry if ulp is not already enabled 2019-07-22 16:04:17 +02:00
sock_reuseport.c bpf: net: Add SO_DETACH_REUSEPORT_BPF 2019-06-15 01:21:19 +02:00
sock.c mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options 2019-07-12 11:05:46 -07:00
stream.c tcp: reduce POLLOUT events caused by TCP_NOTSENT_LOWAT 2018-12-04 21:21:18 -08:00
sysctl_net_core.c net: add high_order_alloc_disable sysctl/static key 2019-06-14 20:18:28 -07:00
timestamping.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61 2019-05-24 17:36:45 +02:00
tso.c
utils.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
xdp.c net: core: page_pool: add user refcnt and reintroduce page_pool_destroy 2019-07-08 14:58:04 -07:00