svn commit: r248587 - stable/9/sys/kern

[Tijl Coosemans]

On 2013-03-21 17:15, Tijl Coosemans wrote:
> Author: tijl
> Date: Thu Mar 21 16:15:34 2013
> New Revision: 248587
> URL: http://svnweb.freebsd.org/changeset/base/248587
> 
> Log:
>   - Fix two possible overflows when testing if ELF program headers are on
>     the first page:
>     1. Cast uint16_t operands in a multiplication to unsigned int because
>        otherwise the implicit promotion to int results in a signed
>        multiplication that can overflow and the behaviour on integer
>        overflow is undefined.
>     2. Replace (offset + size > PAGE_SIZE) with (size > PAGE_SIZE - offset)
>        because the sum may overflow.
>   - Use the same tests to see if the path to the interpreter is on the first
>     page. There's no overflow here because size is already limited by
>     MAXPATHLEN, but the compiler optimises the new tests better. Also fix an
>     off-by-one error.
>   - Simplify tests to see if an ELF note program header is on the first page.
>     This also fixes an off-by-one error.
>   
>   Reviewed by:	kib

Forgot to mention: MFC r248256