528741 - pkix_hash throws a null-argument exception on empty strings

Status: RESOLVED FIXED

(NSS :: Libraries, defect, P1)

Description

[Wan-Teh Chang]

Attachment: Proposed patch

In libpkix, an empty string is represented by a NULL buffer pointer
and a 0 buffer length.

When libpkix hashes an empty string object, it throws a null-argument
exception because of a PKIX_NULLCHECK_TWO macro in pkix_hash that
null-checks the 'bytes' buffer pointer even when 'length' is 0.

The fix is to null-check the 'bytes' buffer pointer only when 'length'
is nonzero.

Comment 1

[Wan-Teh Chang]

Comment on attachment 412415 [details] [diff] [review]
Proposed patch

Nelson, could you review this simple patch?  Is Alexei out of
the office?  Thanks.

Comment 2

[Alexei Volkov]

Comment on attachment 412415 [details] [diff] [review]
Proposed patch

r+

Comment 3

[Wan-Teh Chang]

I checked in the patch on the NSS trunk (NSS 3.12.6).

Checking in pkix_tools.c;
/cvsroot/mozilla/security/nss/lib/libpkix/pkix/util/pkix_tools.c,v  <--  pkix_tools.c
new revision: 1.19; previous revision: 1.18
done

Comment 4

[Alexei Volkov]

Comment on attachment 412415 [details] [diff] [review]
Proposed patch

thx, Wan-teh, for fixing it.