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charset="US-ASCII"; x-default=true X-Rspam-User: X-Stat-Signature: 8ygzzdssufqofkoqerr5gtxtunbdyq3q X-Rspamd-Queue-Id: 81F364000E X-Rspamd-Server: rspam09 X-HE-Tag: 1775094399-300976 X-HE-Meta: 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 Qa+bWb93 XXAiL4LkWGiZ3ZRePOKohBlYLAk+cJKcWCpjgU7y6JkEh6ZQk+GJm236InW8Y+fI9izMlKBN/FuV5RD/iH1qlKmf9yCmA0wky8/NbnM130SRc6U1rsj4I6OAr/hK5HG9Gr86+R3gmuCuNYu/QNcS09JHVAIUVftXTyngDpGeZfrD1llhXy2lx7XWwTk+42kZ8T4wcBloclNeq1YTaioRX3jxVoWuhpQfxL87Xjq4QG+gS3+ty3biJQqaL01VSGIe+Z0q1xtSe1bhYPWmJRKLrGgQca+i7qa5xQSrCcxpcfzRgWd0qCgr63/oUtWGgBkwSCnPwamDPug3JIOIzQLcwcBD/yQ6j++38g/VDwkiQYih2GH1keg8lMi9lO6APMUtDjrxW6WmaJow4Jb0= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Add three more checks for buflen and numwritten. The buflen should be at least two, that means at least one char and the null-end. The error case check is added by checking numwriten < 0 instead of numwritten < 1. And the truncate case is checked. The test will exit if any of these conditions aren't met. Additionally, add more print information when a write failure occurs or a truncated write happens, providing clearer diagnostics. Signed-off-by: Chunyu Hu --- Changes in v8: - go back to ksft_exit_fail_msg in the two error exit path as no clean ksft_exit_fail_perror that supports va_list Changes in v7: - add an empty line before the 'buflen < 1' line. And change to 'buflen < 2 to limit the buflen at least to be 2, so at least one char is allowed. - handle the numwriten < 0 case, which is the error path. - use ksft_exit_fail_perror in error exit path. - use %.*s to print the buf when error happened Changes in v6: - save/restore errno before and after the close(), so the log could show the correct error info on failure. Suggested by AI. Chagnes in v5: - new patch for making improve on write_file. Add more safety checks and diagnostics info in log --- tools/testing/selftests/mm/vm_util.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c index ad96d19d1b85..db94564f4431 100644 --- a/tools/testing/selftests/mm/vm_util.c +++ b/tools/testing/selftests/mm/vm_util.c @@ -767,15 +767,24 @@ int unpoison_memory(unsigned long pfn) void write_file(const char *path, const char *buf, size_t buflen) { - int fd; + int fd, saved_errno; ssize_t numwritten; + if (buflen < 2) + ksft_exit_fail_msg("Incorrect buffer len: %zu\n", buflen); + fd = open(path, O_WRONLY); if (fd == -1) ksft_exit_fail_msg("%s open failed: %s\n", path, strerror(errno)); numwritten = write(fd, buf, buflen - 1); + saved_errno = errno; close(fd); - if (numwritten < 1) - ksft_exit_fail_msg("Write failed\n"); + errno = saved_errno; + if (numwritten < 0) + ksft_exit_fail_msg("%s write(%.*s) failed: %s\n", path, (int)(buflen - 1), + buf, strerror(errno)); + if (numwritten != buflen - 1) + ksft_exit_fail_msg("%s write(%.*s) is truncated, expected %zu bytes, got %zd bytes\n", + path, (int)(buflen - 1), buf, buflen - 1, numwritten); } -- 2.53.0