bpf: map_get_next_key to return first key on NULL
authorTeng Qin <qinteng@fb.com>
Tue, 25 Apr 2017 02:00:37 +0000 (19:00 -0700)
committerDavid S. Miller <davem@davemloft.net>
Tue, 25 Apr 2017 15:57:45 +0000 (11:57 -0400)
commit8fe45924387be6b5c1be59a7eb330790c61d5d10
tree1879f4fd4d14907155b1ebb2fd85ff26aa89ebbe
parent472ecf084a7687347f79720c83881c07407bfd8b
bpf: map_get_next_key to return first key on NULL

When iterating through a map, we need to find a key that does not exist
in the map so map_get_next_key will give us the first key of the map.
This often requires a lot of guessing in production systems.

This patch makes map_get_next_key return the first key when the key
pointer in the parameter is NULL.

Signed-off-by: Teng Qin <qinteng@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/trace/events/bpf.h
kernel/bpf/arraymap.c
kernel/bpf/hashtab.c
kernel/bpf/syscall.c
tools/testing/selftests/bpf/test_maps.c