| Message ID | 20220816205517.682470-1-zhuyifei@google.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 14b20b784f59bdd95f6f1cfb112c9818bcec4d84 |
| Delegated to: | BPF |
| Headers | show |
| Series | [bpf,1/2] bpf: Restrict bpf_sys_bpf to CAP_PERFMON | expand |
Hello: This series was applied to bpf/bpf.git (master) by Daniel Borkmann <daniel@iogearbox.net>: On Tue, 16 Aug 2022 20:55:16 +0000 you wrote: > The verifier cannot perform sufficient validation of any pointers > passed into bpf_attr and treats them as integers rather than pointers. > The helper will then read from arbitrary pointers passed into it. > Restrict the helper to CAP_PERFMON since the security model in > BPF of arbitrary kernel read is CAP_BPF + CAP_PERFMON. > > Fixes: af2ac3e13e45 ("bpf: Prepare bpf syscall to be used from kernel and user space.") > Signed-off-by: YiFei Zhu <zhuyifei@google.com> > > [...] Here is the summary with links: - [bpf,1/2] bpf: Restrict bpf_sys_bpf to CAP_PERFMON https://git.kernel.org/bpf/bpf/c/14b20b784f59 - [bpf,2/2] bpf: Add WARN_ON for recursive prog_run invocation (no matching commit) You are awesome, thank you!
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index a4d40d98428a..27760627370d 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -5197,7 +5197,7 @@ syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_sys_bpf: - return &bpf_sys_bpf_proto; + return !perfmon_capable() ? NULL : &bpf_sys_bpf_proto; case BPF_FUNC_btf_find_by_name_kind: return &bpf_btf_find_by_name_kind_proto; case BPF_FUNC_sys_close:
The verifier cannot perform sufficient validation of any pointers passed into bpf_attr and treats them as integers rather than pointers. The helper will then read from arbitrary pointers passed into it. Restrict the helper to CAP_PERFMON since the security model in BPF of arbitrary kernel read is CAP_BPF + CAP_PERFMON. Fixes: af2ac3e13e45 ("bpf: Prepare bpf syscall to be used from kernel and user space.") Signed-off-by: YiFei Zhu <zhuyifei@google.com> --- kernel/bpf/syscall.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)