Fix integer bounds checking in GNU tar sparse format 1.0 parser

 - Make sure the file actually has that many records before trying
   to read one and fail if not.
 - Use the helper macros for size_t overflow checking instead of
   assuming size_t == uint64_t.
 - Impose a "reasonable" upper bound on the number of data segments
   and insist that there is at least one entry.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/tar/internal.h b/lib/tar/internal.h
index 65e5d45..bea863d 100644
--- a/lib/tar/internal.h
+++ b/lib/tar/internal.h
@@ -42,6 +42,7 @@ enum {
 #define TAR_MAX_SYMLINK_LEN (65536)
 #define TAR_MAX_PATH_LEN (65536)
 #define TAR_MAX_PAX_LEN (65536)
+#define TAR_MAX_SPARSE_ENT (65536)
 
 
 int read_octal(const char *str, int digits, sqfs_u64 *out);