tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 4b35035bcf80ddb47c0112c4fbd84a63a2836a18 commit: 5bd009c7c9a9e888077c07535dc0c70aeab242c3 mm: madvise: return correct bytes advised with process_madvise date: 3 months ago compiler: mips-linux-gcc (GCC) 11.3.0 reproduce (cppcheck warning): # apt-get install cppcheck git checkout 5bd009c7c9a9e888077c07535dc0c70aeab242c3 cppcheck --quiet --enable=style,performance,portability --template=gcc FILE If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> cppcheck warnings: (new ones prefixed by >>) >> mm/madvise.c:1438:6: warning: Redundant assignment of 'ret' to itself. [selfAssignment] ret = (total_len - iov_iter_count(&iter)) ? : ret; ^ cppcheck possible warnings: (new ones prefixed by >>, may not real problems) mm/madvise.c:123:28: warning: Parameter 'anon_name' can be declared with const [constParameter] struct anon_vma_name *anon_name) ^ vim +/ret +1438 mm/madvise.c 1378 1379 SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec, 1380 size_t, vlen, int, behavior, unsigned int, flags) 1381 { 1382 ssize_t ret; 1383 struct iovec iovstack[UIO_FASTIOV], iovec; 1384 struct iovec *iov = iovstack; 1385 struct iov_iter iter; 1386 struct task_struct *task; 1387 struct mm_struct *mm; 1388 size_t total_len; 1389 unsigned int f_flags; 1390 1391 if (flags != 0) { 1392 ret = -EINVAL; 1393 goto out; 1394 } 1395 1396 ret = import_iovec(READ, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter); 1397 if (ret < 0) 1398 goto out; 1399 1400 task = pidfd_get_task(pidfd, &f_flags); 1401 if (IS_ERR(task)) { 1402 ret = PTR_ERR(task); 1403 goto free_iov; 1404 } 1405 1406 if (!process_madvise_behavior_valid(behavior)) { 1407 ret = -EINVAL; 1408 goto release_task; 1409 } 1410 1411 /* Require PTRACE_MODE_READ to avoid leaking ASLR metadata. */ 1412 mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); 1413 if (IS_ERR_OR_NULL(mm)) { 1414 ret = IS_ERR(mm) ? PTR_ERR(mm) : -ESRCH; 1415 goto release_task; 1416 } 1417 1418 /* 1419 * Require CAP_SYS_NICE for influencing process performance. Note that 1420 * only non-destructive hints are currently supported. 1421 */ 1422 if (!capable(CAP_SYS_NICE)) { 1423 ret = -EPERM; 1424 goto release_mm; 1425 } 1426 1427 total_len = iov_iter_count(&iter); 1428 1429 while (iov_iter_count(&iter)) { 1430 iovec = iov_iter_iovec(&iter); 1431 ret = do_madvise(mm, (unsigned long)iovec.iov_base, 1432 iovec.iov_len, behavior); 1433 if (ret < 0) 1434 break; 1435 iov_iter_advance(&iter, iovec.iov_len); 1436 } 1437 > 1438 ret = (total_len - iov_iter_count(&iter)) ? : ret; -- 0-DAY CI Kernel Test Service https://01.org/lkp
