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| author | Alexei Starovoitov <ast@kernel.org> | 2018-12-04 07:46:04 +0100 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-12-04 17:22:02 +0100 |
| commit | c3494801cd1785e2c25f1a5735fa19ddcf9665da (patch) | |
| tree | f3bedbb2deb12948d7765aaac8f4a2e8000fdd73 | |
| parent | bpf: powerpc64: optimize JIT passes for bpf function calls (diff) | |
| download | linux-c3494801cd1785e2c25f1a5735fa19ddcf9665da.tar.xz linux-c3494801cd1785e2c25f1a5735fa19ddcf9665da.zip | |
bpf: check pending signals while verifying programs
Malicious user space may try to force the verifier to use as much cpu
time and memory as possible. Hence check for pending signals
while verifying the program.
Note that suspend of sys_bpf(PROG_LOAD) syscall will lead to EAGAIN,
since the kernel has to release the resources used for program verification.
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| -rw-r--r-- | kernel/bpf/verifier.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 6dd419550aba..751bb30b7c5c 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5148,6 +5148,9 @@ static int do_check(struct bpf_verifier_env *env) goto process_bpf_exit; } + if (signal_pending(current)) + return -EAGAIN; + if (need_resched()) cond_resched(); |