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charset="US-ASCII"; x-default=true X-Stat-Signature: 6z1n455yoymghksjg5tfokrh9hqtqi37 X-Rspamd-Queue-Id: BDC121C0011 X-Rspam-User: X-Rspamd-Server: rspam03 X-HE-Tag: 1774883769-402344 X-HE-Meta: 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 55f3euF6 bC0t9StFZOwAluZ1fLATUeTrIcaSMcDtHN54xQMeX9Aip+77nNruGPafPPTHDKBFBKz8tw4VP7rCLsaFZFTPVKb7k/B6HWtfy60La+sBJMvaGtIzUsj6w4TSXghmNGQUZPOXCyqNOWHVyNidguelmRqkQ2LWxXPQtSmwf/d3WWDXjmkVzeFWZI/ofBDLAnWKaNlviiZLn9qeu5c6DeUGl/bSU+/18iNHtxZiRg3hR7izGXwIt/C4Djkh/6VZrMKTlB+Ul/CA2NsMIYkSirAkWiKqu+Rc89rLKHNGQhfNKrRVwNWmW0fom25xQbyeEDc0I/GAA0oiKAQmA+sRCD3Ey0nRWRRju2wm5j56SRMbMt+vECKC+zsqtDEYWXjZ7egH+s0XWw42MtTxcMi8= 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 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 | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c index ad96d19d1b85..00aaf33387f5 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)); + ksft_exit_fail_perror("%s open failed", path); 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_perror("%s write(%.*s) failed", path, (int)(buflen - 1), + buf); + 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