selftests: bpf: Use a temporary file in test_sockmap

Use a proper temporary file for sendpage tests. This means that running
the tests doesn't clutter the working directory, and allows running the
test on read-only filesystems.

Fixes: 16962b2404ac ("bpf: sockmap, add selftests")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200124112754.19664-2-lmb@cloudflare.com

diff --git a/tools/testing/selftests/bpf/test_sockmap.c b/tools/testing/selftests/bpf/test_sockmap.c
index 4a85151..779e11d 100644 (file)
--- a/tools/testing/selftests/bpf/test_sockmap.c
+++ b/tools/testing/selftests/bpf/test_sockmap.c
@@ -331,7 +331,7 @@ static int msg_loop_sendpage(int fd, int iov_length, int cnt,
        FILE *file;
        int i, fp;
 
-       file = fopen(".sendpage_tst.tmp", "w+");
+       file = tmpfile();
        if (!file) {
                perror("create file for sendpage");
                return 1;
@@ -340,13 +340,8 @@ static int msg_loop_sendpage(int fd, int iov_length, int cnt,
                fwrite(&k, sizeof(char), 1, file);
        fflush(file);
        fseek(file, 0, SEEK_SET);
-       fclose(file);
 
-       fp = open(".sendpage_tst.tmp", O_RDONLY);
-       if (fp < 0) {
-               perror("reopen file for sendpage");
-               return 1;
-       }
+       fp = fileno(file);
 
        clock_gettime(CLOCK_MONOTONIC, &s->start);
        for (i = 0; i < cnt; i++) {
@@ -354,11 +349,11 @@ static int msg_loop_sendpage(int fd, int iov_length, int cnt,
 
                if (!drop && sent < 0) {
                        perror("send loop error");
-                       close(fp);
+                       fclose(file);
                        return sent;
                } else if (drop && sent >= 0) {
                        printf("sendpage loop error expected: %i\n", sent);
-                       close(fp);
+                       fclose(file);
                        return -EIO;
                }
 
@@ -366,7 +361,7 @@ static int msg_loop_sendpage(int fd, int iov_length, int cnt,
                        s->bytes_sent += sent;
        }
        clock_gettime(CLOCK_MONOTONIC, &s->end);
-       close(fp);
+       fclose(file);
        return 0;
 }