From: Xu Kuohai xukuohai@huawei.com
mainline inclusion from mainline-v6.12-rc1 commit 21c7063f6d08ab9afa088584939791bee0c177e5 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYPJF CVE: CVE-2024-47703
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
--------------------------------
Add a disabled hooks list for BPF LSM. progs being attached to the listed hooks will be rejected by the verifier.
Suggested-by: KP Singh kpsingh@kernel.org Signed-off-by: Xu Kuohai xukuohai@huawei.com Link: https://lore.kernel.org/r/20240719110059.797546-2-xukuohai@huaweicloud.com Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Andrii Nakryiko andrii@kernel.org
Conflicts: kernel/bpf/bpf_lsm.c [The conflicts are due to we did not backport a04a1198088] Signed-off-by: Tengda Wu wutengda2@huawei.com --- kernel/bpf/bpf_lsm.c | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-)
diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c index e14c822f8911..ee2b61f459a5 100644 --- a/kernel/bpf/bpf_lsm.c +++ b/kernel/bpf/bpf_lsm.c @@ -36,6 +36,23 @@ BTF_SET_START(bpf_lsm_hooks) #undef LSM_HOOK BTF_SET_END(bpf_lsm_hooks)
+BTF_SET_START(bpf_lsm_disabled_hooks) +BTF_ID(func, bpf_lsm_vm_enough_memory) +BTF_ID(func, bpf_lsm_inode_need_killpriv) +BTF_ID(func, bpf_lsm_inode_getsecurity) +BTF_ID(func, bpf_lsm_inode_listsecurity) +BTF_ID(func, bpf_lsm_inode_copy_up_xattr) +BTF_ID(func, bpf_lsm_getprocattr) +BTF_ID(func, bpf_lsm_setprocattr) +#ifdef CONFIG_KEYS +BTF_ID(func, bpf_lsm_key_getsecurity) +#endif +#ifdef CONFIG_AUDIT +BTF_ID(func, bpf_lsm_audit_rule_match) +#endif +BTF_ID(func, bpf_lsm_ismaclabel) +BTF_SET_END(bpf_lsm_disabled_hooks) + /* List of LSM hooks that should operate on 'current' cgroup regardless * of function signature. */ @@ -97,15 +114,24 @@ void bpf_lsm_find_cgroup_shim(const struct bpf_prog *prog, int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog, const struct bpf_prog *prog) { + u32 btf_id = prog->aux->attach_btf_id; + const char *func_name = prog->aux->attach_func_name; + if (!prog->gpl_compatible) { bpf_log(vlog, "LSM programs must have a GPL compatible license\n"); return -EINVAL; }
- if (!btf_id_set_contains(&bpf_lsm_hooks, prog->aux->attach_btf_id)) { + if (btf_id_set_contains(&bpf_lsm_disabled_hooks, btf_id)) { + bpf_log(vlog, "attach_btf_id %u points to disabled hook %s\n", + btf_id, func_name); + return -EINVAL; + } + + if (!btf_id_set_contains(&bpf_lsm_hooks, btf_id)) { bpf_log(vlog, "attach_btf_id %u points to wrong type name %s\n", - prog->aux->attach_btf_id, prog->aux->attach_func_name); + btf_id, func_name); return -EINVAL; }