x86/sev: Fix calculation of end address based on number of pages

[ Upstream commit 5dee19b6 ]

When calculating an end address based on an unsigned int number of pages,
any value greater than or equal to 0x100000 that is shift PAGE_SHIFT bits
results in a 0 value, resulting in an invalid end address. Change the
number of pages variable in various routines from an unsigned int to an
unsigned long to calculate the end address correctly.

Fixes: 5e5ccff6 ("x86/sev: Add helper for validating pages in early enc attribute changes")
Fixes: dc3f3d24 ("x86/mm: Validate memory when changing the C-bit")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/6a6e4eea0e1414402bac747744984fa4e9c01bb6.1686063086.git.thomas.lendacky@amd.com


Signed-off-by: Sasha Levin <sashal@kernel.org>