gh-152718: Tighten comments and shorten the NEWS entry

Author: tonghuaroot

Misc/NEWS.d/next/Library/2026-07-01-12-00-00.gh-issue-152718.pr0f1l.rst

@@ -1,4 +1,2 @@
 Fix unbounded memory allocation in the :mod:`profiling.sampling` binary profile
-reader, which trusted the string and frame table counts declared in a file's
-footer before allocating. A malformed file can no longer make the reader
-attempt a huge allocation.
+reader when a file declares more string or frame entries than it contains.

Modules/_remote_debugging/binary_io.h

@@ -91,8 +91,7 @@ static_assert(SAMPLE_HEADER_FIXED_SIZE == 13,
 static_assert(FILE_FOOTER_SIZE == 32,
              "FILE_FOOTER_SIZE must remain 32");
 
-/* Minimum on-disk bytes per table entry: a string is a >=1-byte length
- * varint; a frame is six >=1-byte varints plus the opcode byte. */
+/* Minimum on-disk bytes of a string (1) and frame (7) table entry. */
 #define MIN_STRING_ENTRY_SIZE 1
 #define MIN_FRAME_ENTRY_SIZE  7
 

Modules/_remote_debugging/binary_io_reader.c

@@ -240,7 +240,6 @@ reader_decompress_samples(BinaryReader *reader, const uint8_t *data)
 static inline int
 reader_parse_string_table(BinaryReader *reader, const uint8_t *data, size_t file_size)
 {
-    /* Reject a count larger than the remaining bytes can hold. */
     size_t max_strings =
         (file_size - reader->string_table_offset) / MIN_STRING_ENTRY_SIZE;
     if (reader->strings_count > max_strings) {
@@ -290,7 +289,6 @@ reader_parse_frame_table(BinaryReader *reader, const uint8_t *data, size_t file_
     }
 #endif
 
-    /* Reject a count larger than the remaining bytes can hold. */
     size_t max_frames =
         (file_size - reader->frame_table_offset) / MIN_FRAME_ENTRY_SIZE;
     if (reader->frames_count > max_frames) {