diff options
| author | Rabin Vincent | 2016-01-12 20:17:08 +0100 |
|---|---|---|
| committer | David S. Miller | 2016-01-12 15:55:39 -0500 |
| commit | 06928b3870d213cb42b00e2949419f2d44b9d45f (patch) | |
| tree | d1427c587b190b02f7d2e5b842c1804f38386128 /net | |
| parent | 03d84a5f83a67e692af00a3d3901e7820e3e84d5 (diff) | |
net: bpf: reject invalid shifts
On ARM64, a BUG() is triggered in the eBPF JIT if a filter with a
constant shift that can't be encoded in the immediate field of the
UBFM/SBFM instructions is passed to the JIT. Since these shifts
amounts, which are negative or >= regsize, are invalid, reject them in
the eBPF verifier and the classic BPF filter checker, for all
architectures.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/filter.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/net/core/filter.c b/net/core/filter.c index 672eefbfbe99..37157c4c1a78 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -777,6 +777,11 @@ static int bpf_check_classic(const struct sock_filter *filter, if (ftest->k == 0) return -EINVAL; break; + case BPF_ALU | BPF_LSH | BPF_K: + case BPF_ALU | BPF_RSH | BPF_K: + if (ftest->k >= 32) + return -EINVAL; + break; case BPF_LD | BPF_MEM: case BPF_LDX | BPF_MEM: case BPF_ST: |