3.16.7-ckt24 -stable review patch. If anyone has any objections, please let me know.
---8<------------------------------------------------------------ From: Rabin Vincent <[email protected]> commit 229394e8e62a4191d592842cf67e80c62a492937 upstream. 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 <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Acked-by: Daniel Borkmann <[email protected]> Signed-off-by: David S. Miller <[email protected]> [ luis: backported to 3.16: - drop changes to eBPF verifier, only added in 3.18 kernel - function rename: bpf_check_classic() -> sk_chk_filter() ] Signed-off-by: Luis Henriques <[email protected]> --- net/core/filter.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/core/filter.c b/net/core/filter.c index 3139f966a178..dfc5f31dc5a1 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -1251,6 +1251,11 @@ int sk_chk_filter(struct sock_filter *filter, unsigned int flen) 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:
