On 8/12/22 12:18 PM, Roberto Sassu wrote:
Allow the bpf_dynptr_kern parameter to be specified in kfuncs. Also, ensure that the dynamic pointer is valid and initialized.
Cc: Joanne Koong joannelkoong@gmail.com Signed-off-by: Roberto Sassu roberto.sassu@huawei.com
include/linux/bpf_verifier.h | 3 +++ kernel/bpf/btf.c | 22 ++++++++++++++++++++++ kernel/bpf/verifier.c | 4 ++-- 3 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h index 2e3bad8640dc..55876fbdbae2 100644 --- a/include/linux/bpf_verifier.h +++ b/include/linux/bpf_verifier.h @@ -560,6 +560,9 @@ int check_kfunc_mem_size_reg(struct bpf_verifier_env *env, struct bpf_reg_state u32 regno); int check_mem_reg(struct bpf_verifier_env *env, struct bpf_reg_state *reg, u32 regno, u32 mem_size); +bool is_dynptr_reg_valid_init(struct bpf_verifier_env *env,
struct bpf_reg_state *reg,enum bpf_arg_type arg_type);/* this lives here instead of in bpf.h because it needs to dereference tgt_prog */ static inline u64 bpf_trampoline_compute_key(const struct bpf_prog *tgt_prog, diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index e49b3b6d48ad..86e63f2ee5da 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -195,6 +195,10 @@ i < btf_type_vlen(struct_type); \ i++, member++) +#define stringify_struct(x) \
- ({ BUILD_BUG_ON(sizeof(struct x) < 0); \
__stringify(x); })
I'd say lets move this to include/linux/btf.h with a comment explaining the BUILD_BUG_ON() which ensures the struct actually exits.
If there's ever use outside of BTF, it could be relocated to include/linux/stringify.h.
DEFINE_IDR(btf_idr); DEFINE_SPINLOCK(btf_idr_lock);