bpf: fix pseudo calls for program loaded from ELF

[dpdk.git] / lib / librte_bpf / bpf_load.c

diff --git a/lib/librte_bpf/bpf_load.c b/lib/librte_bpf/bpf_load.c
index d1c9abd..194103e 100644 (file)
--- a/lib/librte_bpf/bpf_load.c
+++ b/lib/librte_bpf/bpf_load.c
@@ -51,17 +51,64 @@ bpf_load(const struct rte_bpf_prm *prm)
        return bpf;
 }
 
+/*
+ * Check that user provided external symbol.
+ */
+static int
+bpf_check_xsym(const struct rte_bpf_xsym *xsym)
+{
+       uint32_t i;
+
+       if (xsym->name == NULL)
+               return -EINVAL;
+
+       if (xsym->type == RTE_BPF_XTYPE_VAR) {
+               if (xsym->var.desc.type == RTE_BPF_ARG_UNDEF)
+                       return -EINVAL;
+       } else if (xsym->type == RTE_BPF_XTYPE_FUNC) {
+
+               if (xsym->func.nb_args > EBPF_FUNC_MAX_ARGS)
+                       return -EINVAL;
+
+               /* check function arguments */
+               for (i = 0; i != xsym->func.nb_args; i++) {
+                       if (xsym->func.args[i].type == RTE_BPF_ARG_UNDEF)
+                               return -EINVAL;
+               }
+
+               /* check return value info */
+               if (xsym->func.ret.type != RTE_BPF_ARG_UNDEF &&
+                               xsym->func.ret.size == 0)
+                       return -EINVAL;
+       } else
+               return -EINVAL;
+
+       return 0;
+}
+
 __rte_experimental struct rte_bpf *
 rte_bpf_load(const struct rte_bpf_prm *prm)
 {
        struct rte_bpf *bpf;
        int32_t rc;
+       uint32_t i;
 
-       if (prm == NULL || prm->ins == NULL) {
+       if (prm == NULL || prm->ins == NULL ||
+                       (prm->nb_xsym != 0 && prm->xsym == NULL)) {
                rte_errno = EINVAL;
                return NULL;
        }
 
+       rc = 0;
+       for (i = 0; i != prm->nb_xsym && rc == 0; i++)
+               rc = bpf_check_xsym(prm->xsym + i);
+
+       if (rc != 0) {
+               rte_errno = -rc;
+               RTE_BPF_LOG(ERR, "%s: %d-th xsym is invalid\n", __func__, i);
+               return NULL;
+       }
+
        bpf = bpf_load(prm);
        if (bpf == NULL) {
                rte_errno = ENOMEM;
@@ -84,7 +131,8 @@ rte_bpf_load(const struct rte_bpf_prm *prm)
        return bpf;
 }
 
-__rte_experimental __attribute__ ((weak)) struct rte_bpf *
+#ifndef RTE_LIBRTE_BPF_ELF
+__rte_experimental struct rte_bpf *
 rte_bpf_elf_load(const struct rte_bpf_prm *prm, const char *fname,
        const char *sname)
 {
@@ -99,3 +147,4 @@ rte_bpf_elf_load(const struct rte_bpf_prm *prm, const char *fname,
        rte_errno = ENOTSUP;
        return NULL;
 }
+#endif