1 files changed, 131 insertions, 0 deletions

diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index a411fc17d265..4266ffde07ca 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -18,6 +18,9 @@
 #include <linux/sched.h>
 #include <linux/uidgid.h>
 #include <linux/filter.h>
+#include <linux/ctype.h>
+
+#include "../../lib/kstrtox.h"
 
 /* If kernel subsystem is allowing eBPF programs to call this function,
  * inside its own verifier_ops->get_func_proto() callback it should return
@@ -363,4 +366,132 @@ const struct bpf_func_proto bpf_get_local_storage_proto = {
         .arg2_type      = ARG_ANYTHING,
 };
 #endif
+
+#define BPF_STRTOX_BASE_MASK 0x1F
+
+static int __bpf_strtoull(const char *buf, size_t buf_len, u64 flags,
+                          unsigned long long *res, bool *is_negative)
+{
+        unsigned int base = flags & BPF_STRTOX_BASE_MASK;
+        const char *cur_buf = buf;
+        size_t cur_len = buf_len;
+        unsigned int consumed;
+        size_t val_len;
+        char str[64];
+
+        if (!buf || !buf_len || !res || !is_negative)
+                return -EINVAL;
+
+        if (base != 0 && base != 8 && base != 10 && base != 16)
+                return -EINVAL;
+
+        if (flags & ~BPF_STRTOX_BASE_MASK)
+                return -EINVAL;
+
+        while (cur_buf < buf + buf_len && isspace(*cur_buf))
+                ++cur_buf;
+
+        *is_negative = (cur_buf < buf + buf_len && *cur_buf == '-');
+        if (*is_negative)
+                ++cur_buf;
+
+        consumed = cur_buf - buf;
+        cur_len -= consumed;
+        if (!cur_len)
+                return -EINVAL;
+
+        cur_len = min(cur_len, sizeof(str) - 1);
+        memcpy(str, cur_buf, cur_len);
+        str[cur_len] = '\0';
+        cur_buf = str;
+
+        cur_buf = _parse_integer_fixup_radix(cur_buf, &base);
+        val_len = _parse_integer(cur_buf, base, res);
+
+        if (val_len & KSTRTOX_OVERFLOW)
+                return -ERANGE;
+
+        if (val_len == 0)
+                return -EINVAL;
+
+        cur_buf += val_len;
+        consumed += cur_buf - str;
+
+        return consumed;
+}
+
+static int __bpf_strtoll(const char *buf, size_t buf_len, u64 flags,
+                         long long *res)
+{
+        unsigned long long _res;
+        bool is_negative;
+        int err;
+
+        err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
+        if (err < 0)
+                return err;
+        if (is_negative) {
+                if ((long long)-_res > 0)
+                        return -ERANGE;
+                *res = -_res;
+        } else {
+                if ((long long)_res < 0)
+                        return -ERANGE;
+                *res = _res;
+        }
+        return err;
+}
+
+BPF_CALL_4(bpf_strtol, const char *, buf, size_t, buf_len, u64, flags,
+           long *, res)
+{
+        long long _res;
+        int err;
+
+        err = __bpf_strtoll(buf, buf_len, flags, &_res);
+        if (err < 0)
+                return err;
+        if (_res != (long)_res)
+                return -ERANGE;
+        *res = _res;
+        return err;
+}
+
+const struct bpf_func_proto bpf_strtol_proto = {
+        .func           = bpf_strtol,
+        .gpl_only       = false,
+        .ret_type       = RET_INTEGER,
+        .arg1_type      = ARG_PTR_TO_MEM,
+        .arg2_type      = ARG_CONST_SIZE,
+        .arg3_type      = ARG_ANYTHING,
+        .arg4_type      = ARG_PTR_TO_LONG,
+};
+
+BPF_CALL_4(bpf_strtoul, const char *, buf, size_t, buf_len, u64, flags,
+           unsigned long *, res)
+{
+        unsigned long long _res;
+        bool is_negative;
+        int err;
+
+        err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
+        if (err < 0)
+                return err;
+        if (is_negative)
+                return -EINVAL;
+        if (_res != (unsigned long)_res)
+                return -ERANGE;
+        *res = _res;
+        return err;
+}
+
+const struct bpf_func_proto bpf_strtoul_proto = {
+        .func           = bpf_strtoul,
+        .gpl_only       = false,
+        .ret_type       = RET_INTEGER,
+        .arg1_type      = ARG_PTR_TO_MEM,
+        .arg2_type      = ARG_CONST_SIZE,
+        .arg3_type      = ARG_ANYTHING,
+        .arg4_type      = ARG_PTR_TO_LONG,
+};
 #endif