Limit write requests to at most INT_MAX.

This prevents a certain common programming error (passing -1 to write)
from leading to other problems deeper in the library.

diff --git a/libarchive/archive_write.c b/libarchive/archive_write.c
index eede5e05756d2c535a8e74c866972b019186c12e..be85621508d51df04ccedb3910cfe08e0dfa5b4f 100644 (file)
--- a/libarchive/archive_write.c
+++ b/libarchive/archive_write.c
@@ -673,8 +673,13 @@ static ssize_t
 _archive_write_data(struct archive *_a, const void *buff, size_t s)
 {
        struct archive_write *a = (struct archive_write *)_a;
+       const size_t max_write = INT_MAX;
+
        archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
            ARCHIVE_STATE_DATA, "archive_write_data");
+       /* In particular, this catches attempts to pass negative values. */
+       if (s > max_write)
+               s = max_write;
        archive_clear_error(&a->archive);
        return ((a->format_write_data)(a, buff, s));
 }