alistair23-linux/kernel/bpf
John Fastabend 4fcfdfb833 bpf: sockmap, fix double page_put on ENOMEM error in redirect path
In the case where the socket memory boundary is hit the redirect
path returns an ENOMEM error. However, before checking for this
condition the redirect scatterlist buffer is setup with a valid
page and length. This is never unwound so when the buffers are
released latter in the error path we do a put_page() and clear
the scatterlist fields. But, because the initial error happens
before completing the scatterlist buffer we end up with both the
original buffer and the redirect buffer pointing to the same page
resulting in duplicate put_page() calls.

To fix this simply move the initial configuration of the redirect
scatterlist buffer below the sock memory check.

Found this while running TCP_STREAM test with netperf using Cilium.

Fixes: fa246693a1 ("bpf: sockmap, BPF_F_INGRESS flag for BPF_SK_SKB_STREAM_VERDICT")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-24 00:49:45 +02:00
..
arraymap.c bpf: sockmap, map_release does not hold refcnt for pinned maps 2018-04-24 00:49:45 +02:00
bpf_lru_list.c
bpf_lru_list.h bpf: Only set node->ref = 1 if it has not been set 2017-09-01 09:57:39 -07:00
cgroup.c bpf: Hooks for sys_bind 2018-03-31 02:15:18 +02:00
core.c bpf/tracing: fix a deadlock in perf_event_detach_bpf_prog 2018-04-11 01:01:40 +02:00
cpumap.c bpf: cpumap: use GFP_KERNEL instead of GFP_ATOMIC in __cpu_map_entry_alloc() 2018-02-14 15:34:27 +01:00
devmap.c bpf: add helper for copying attrs to struct bpf_map 2018-01-14 23:36:29 +01:00
disasm.c bpf: Remove struct bpf_verifier_env argument from print_bpf_insn 2018-03-23 17:38:57 +01:00
disasm.h bpf: Remove struct bpf_verifier_env argument from print_bpf_insn 2018-03-23 17:38:57 +01:00
hashtab.c bpf: add helper for copying attrs to struct bpf_map 2018-01-14 23:36:29 +01:00
helpers.c
inode.c bpf: comment why dots in filenames under BPF virtual FS are not allowed 2018-03-09 10:30:30 +01:00
lpm_trie.c bpf: fix rcu lockdep warning for lpm_trie map_free callback 2018-02-22 21:29:12 +01:00
Makefile bpf: only build sockmap with CONFIG_INET 2018-01-04 19:01:14 +01:00
map_in_map.c
map_in_map.h
offload.c bpf: offload: report device information about offloaded maps 2018-01-18 22:54:25 +01:00
percpu_freelist.c bpf: fix lockdep splat 2017-11-15 19:46:32 +09:00
percpu_freelist.h
sockmap.c bpf: sockmap, fix double page_put on ENOMEM error in redirect path 2018-04-24 00:49:45 +02:00
stackmap.c bpf: extend stackmap to save binary_build_id+offset instead of address 2018-03-15 01:09:28 +01:00
syscall.c bpf: sockmap, map_release does not hold refcnt for pinned maps 2018-04-24 00:49:45 +02:00
tnum.c
verifier.c bpf: Hooks for sys_bind 2018-03-31 02:15:18 +02:00