linux/include
Daniel Borkmann 65073a6733 bpf: fix null pointer deref in bpf_prog_test_run_xdp
syzkaller was able to generate the following XDP program ...

  (18) r0 = 0x0
  (61) r5 = *(u32 *)(r1 +12)
  (04) (u32) r0 += (u32) 0
  (95) exit

... and trigger a NULL pointer dereference in ___bpf_prog_run()
via bpf_prog_test_run_xdp() where this was attempted to run.

Reason is that recent xdp_rxq_info addition to XDP programs
updated all drivers, but not bpf_prog_test_run_xdp(), where
xdp_buff is set up. Thus when context rewriter does the deref
on the netdev it's NULL at runtime. Fix it by using xdp_rxq
from loopback dev. __netif_get_rx_queue() helper can also be
reused in various other locations later on.

Fixes: 02dd3291b2 ("bpf: finally expose xdp_rxq_info to XDP bpf-programs")
Reported-by: syzbot+1eb094057b338eb1fc00@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-01 07:43:56 -08:00
..
acpi Merge branches 'acpi-gpio', 'acpi-button', 'acpi-battery' and 'acpi-video' 2018-01-18 03:02:16 +01:00
asm-generic Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
clocksource
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-01-31 14:22:45 -08:00
drm Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-01-30 17:58:07 -08:00
dt-bindings
keys
kvm KVM: arm/arm64: timer: Don't set irq as forwarded if no usable GIC 2017-12-18 10:53:23 +01:00
linux bpf: fix null pointer deref in bpf_prog_test_run_xdp 2018-02-01 07:43:56 -08:00
math-emu
media
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
pcmcia
ras
rdma RDMA/restrack: Add general infrastructure to track RDMA resources 2018-01-29 20:21:39 -07:00
scsi First merge window pull request for 4.16 2018-01-31 12:05:10 -08:00
soc
sound Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-01-30 17:58:07 -08:00
target
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
video
xen xen: fixes for 4.15-rc5 2017-12-22 12:30:10 -08:00