bpf: allow . char as part of the object name

Trivial addition to allow '.' aside from '_' as "special" characters
in the object name. Used to allow for substrings in maps from loader
side such as ".bss", ".data", ".rodata", but could also be useful for
other purposes.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index b3ce516e5a20..198c9680bf0d 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -474,10 +474,10 @@ static int bpf_obj_name_cpy(char *dst, const char *src)
         const char *end = src + BPF_OBJ_NAME_LEN;
 
         memset(dst, 0, BPF_OBJ_NAME_LEN);
-
-        /* Copy all isalnum() and '_' char */
+        /* Copy all isalnum(), '_' and '.' chars. */
         while (src < end && *src) {
-                if (!isalnum(*src) && *src != '_')
+                if (!isalnum(*src) &&
+                    *src != '_' && *src != '.')
                         return -EINVAL;
                 *dst++ = *src++;
         }