diff options
| author | James Morse <james.morse@arm.com> | 2025-04-29 16:03:38 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-05-18 08:24:58 +0200 |
| commit | e5f5100f1c64ac6c72671b2cf6b46542fce93706 (patch) | |
| tree | 691ed147c21bc7ec3b7006c100a0767008b3c3c3 | |
| parent | 38c345fd54afd9d6ed8d3fcddf3f6ea23887bf78 (diff) | |
arm64: bpf: Only mitigate cBPF programs loaded by unprivileged users
commit f300769ead032513a68e4a02e806393402e626f8 upstream.
Support for eBPF programs loaded by unprivileged users is typically
disabled. This means only cBPF programs need to be mitigated for BHB.
In addition, only mitigate cBPF programs that were loaded by an
unprivileged user. Privileged users can also load the same program
via eBPF, making the mitigation pointless.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/arm64/net/bpf_jit_comp.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index 19e6ab47f2ec..515c411c2c83 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -870,6 +870,9 @@ static void __maybe_unused build_bhb_mitigation(struct jit_ctx *ctx) arm64_get_spectre_v2_state() == SPECTRE_VULNERABLE) return; + if (capable(CAP_SYS_ADMIN)) + return; + if (supports_clearbhb(SCOPE_SYSTEM)) { emit(aarch64_insn_gen_hint(AARCH64_INSN_HINT_CLEARBHB), ctx); return; |