fold_binary in fold-const.c in GNU Compiler Collection (gcc) 4.1 improperly...

Vulnerability Description

fold_binary in fold-const.c in GNU Compiler Collection (gcc) 4.1 improperly handles pointer overflow when folding a certain expr comparison to a corresponding offset comparison in cases other than EQ_EXPR and NE_EXPR, which might introduce buffer overflow vulnerabilities into applications that could be exploited by context-dependent attackers.NOTE: the vendor states that the essence of the issue is "not correctly interpreting an offset to a pointer as a signed value."

References

• http://www.securityfocus.com/archive/1/431297/100/0/threaded
• http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26763
• http://www.securityfocus.com/archive/1/431245/100/0/threaded
• http://www.securityfocus.com/archive/1/431319/100/0/threaded
• http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=356896
• http://www.securityfocus.com/archive/1/431184/100/0/threaded
• http://gcc.gnu.org/ml/gcc-bugs/2006-04/msg01297.html
• http://gcc.gnu.org/viewcvs/branches/gcc-4_1-branch/gcc/fold-const.c?r1=110549&r2=112698&pathrev=112698&diff_format=h
• http://gcc.gnu.org/ml/gcc-bugs/2006-04/msg01298.html