Integer overflow in the uvm_map_isavail function in uvm/uvm_map.c in OpenBSD 5.9 allows local users to cause a denial of service (kernel panic) via a crafted mmap call, which triggers the new mapping to overlap with an existing mapping.
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
| Link | Tags |
|---|---|
| http://www.openwall.com/lists/oss-security/2016/08/02/8 | mailing list exploit third party advisory |
| http://ftp.openbsd.org/pub/OpenBSD/patches/5.9/common/023_uvmisavail.patch.sig | patch |
| http://www.openwall.com/lists/oss-security/2016/08/02/12 | mailing list exploit third party advisory |
| http://www.securityfocus.com/bid/92264 | vdb entry |