proc: fixup proc-pid-vm test

Silly sizeof(pointer) vs sizeof(uint8_t[]) bug.

Link: http://lkml.kernel.org/r/20190414123009.GA12971@avx2
Fixes: e483b020 ("proc: test /proc/*/maps, smaps, smaps_rollup, statm")
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/testing/selftests/proc/proc-pid-vm.c

@@ -187,8 +187,8 @@ static int make_exe(const uint8_t *payload, size_t len)
 	ph.p_offset = 0;
 	ph.p_vaddr = VADDR;
 	ph.p_paddr = 0;
-	ph.p_filesz = sizeof(struct elf64_hdr) + sizeof(struct elf64_phdr) + sizeof(payload);
-	ph.p_memsz = sizeof(struct elf64_hdr) + sizeof(struct elf64_phdr) + sizeof(payload);
+	ph.p_filesz = sizeof(struct elf64_hdr) + sizeof(struct elf64_phdr) + len;
+	ph.p_memsz = sizeof(struct elf64_hdr) + sizeof(struct elf64_phdr) + len;
 	ph.p_align = 4096;
 
 	fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_EXCL|O_TMPFILE, 0700);