linux/kernel/bpf
John Fastabend abaeb096ca bpf: sockmap, fix error handling in redirect failures
When a redirect failure happens we release the buffers in-flight
without calling a sk_mem_uncharge(), the uncharge is called before
dropping the sock lock for the redirecte, however we missed updating
the ring start index. When no apply actions are in progress this
is OK because we uncharge the entire buffer before the redirect.
But, when we have apply logic running its possible that only a
portion of the buffer is being redirected. In this case we only
do memory accounting for the buffer slice being redirected and
expect to be able to loop over the BPF program again and/or if
a sock is closed uncharge the memory at sock destruct time.

With an invalid start index however the program logic looks at
the start pointer index, checks the length, and when seeing the
length is zero (from the initial release and failure to update
the pointer) aborts without uncharging/releasing the remaining
memory.

The fix for this is simply to update the start index. To avoid
fixing this error in two locations we do a small refactor and
remove one case where it is open-coded. Then fix it in the
single function.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-02 15:30:45 -07:00
..
Makefile bpf: only build sockmap with CONFIG_INET 2018-01-04 19:01:14 +01:00
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: Lower the PERCPU_NR_SCANS from 16 to 4 2017-04-17 13:55:52 -04:00
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 bpf: rename ARG_PTR_TO_STACK 2017-01-09 16:56:27 -05:00
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
map_in_map.c bpf: Add syscall lookup support for fd array and htab 2017-06-29 13:13:25 -04:00
map_in_map.h bpf: Add syscall lookup support for fd array and htab 2017-06-29 13:13:25 -04:00
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 bpf: introduce percpu_freelist 2016-03-08 15:28:31 -05:00
sockmap.c bpf: sockmap, fix error handling in redirect failures 2018-05-02 15:30:45 -07:00
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 bpf/verifier: track signed and unsigned min/max values 2017-08-08 17:51:34 -07:00
verifier.c bpf: Hooks for sys_bind 2018-03-31 02:15:18 +02:00