ext/standard: fix out-of-bounds access in the ftp:// directory stream#22768
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ext/standard: fix out-of-bounds access in the ftp:// directory stream#22768iliaal wants to merge 1 commit into
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php_ftp_dirstream_read() sized the basename copy with MIN(sizeof(ent->d_name), ZSTR_LEN(basename) - 1) and wrote the terminator at [tmp_len - 1]. An empty listing line leaves a basename of length 1, so tmp_len is 0 and the NUL lands one byte before d_name; a slash-only line leaves length 0, so the subtraction underflows to SIZE_MAX and memcpy() reads 4096 bytes past the interned empty string. The same off-by-one truncated entry names that do not end in CRLF. Closes phpGH-22768
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php_ftp_dirstream_read()sized the basename copy withMIN(sizeof, len - 1)and terminated at[tmp_len - 1]. An empty listing line gives a basename of length 1, so tmp_len is 0 and the terminator lands one byte before d_name; a slash-only line gives length 0, so len - 1 underflows to SIZE_MAX and memcpy reads 4096 bytes past the interned empty string. ASAN flags both. The same off-by-one truncated entry names that do not end in CRLF, which opendir-002 and opendir-004 had baked in as expected output.Floor: PHP-8.4.