John Fastabend 3e104c2381 bpf, sockmap: msg_pop_data can incorrecty set an sge length ... When sk_msg_pop() is called where the pop operation is working on the end of a sge element and there is no additional trailing data and there _is_ data in front of pop, like the following case, |____________a_____________|__pop__| We have out of order operations where we incorrectly set the pop variable so that instead of zero'ing pop we incorrectly leave it untouched, effectively. This can cause later logic to shift the buffers around believing it should pop extra space. The result is we have 'popped' more data then we expected potentially breaking program logic. It took us a while to hit this case because typically we pop headers which seem to rarely be at the end of a scatterlist elements but we can't rely on this. Fixes: 7246d8ed4d ("bpf: helper to pop data from messages") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/158861288359.14306.7654891716919968144.stgit@john-Precision-5820-Tower		2020-05-06 00:22:15 +02:00
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bpf_sk_storage.c
datagram.c
datagram.h
dev_addr_lists.c
dev_ioctl.c
dev.c	xdp: Reset prog in dev_change_xdp_fd when fd is negative	2020-04-14 21:38:02 +02:00
devlink.c
drop_monitor.c
dst_cache.c
dst.c
failover.c
fib_notifier.c
fib_rules.c
filter.c	bpf, sockmap: msg_pop_data can incorrecty set an sge length	2020-05-06 00:22:15 +02:00
flow_dissector.c
flow_offload.c
gen_estimator.c
gen_stats.c
gro_cells.c
hwbm.c
link_watch.c
lwt_bpf.c
lwtunnel.c
Makefile
neighbour.c	neigh: support smaller retrans_time settting	2020-04-02 17:55:26 -07:00
net_namespace.c
net-procfs.c
net-sysfs.c	net-sysfs: remove redundant assignment to variable ret	2020-04-09 10:14:53 -07:00
net-sysfs.h
net-traces.c
netclassid_cgroup.c	cgroup, netclassid: remove double cond_resched	2020-04-21 15:44:30 -07:00
netevent.c
netpoll.c
netprio_cgroup.c
page_pool.c
pktgen.c
ptp_classifier.c
request_sock.c
rtnetlink.c
scm.c
secure_seq.c
skbuff.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2020-03-30 20:48:43 -07:00
skmsg.c
sock_diag.c
sock_map.c
sock_reuseport.c
sock.c	net: remove obsolete comment	2020-04-25 20:49:32 -07:00
stream.c
sysctl_net_core.c
timestamping.c
tso.c
utils.c
xdp.c