2023-06-22 13:51:24

by Tom Lendacky

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Subject: [PATCH] x86/sev: Change npages to unsigned long in snp_accept_memory()

In snp_accept_memory(), the npages variables value is calculated from
phys_addr_t variables but is an unsigned int. A very large range passed
into snp_accept_memory() could lead to truncating npages to zero.

Fixes: 6c3211796326 ("x86/sev: Add SNP-specific unaccepted memory support")
Signed-off-by: Tom Lendacky <[email protected]>
---
arch/x86/kernel/sev.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index 1ee7bed453de..2b0342a03c1b 100644
--- a/arch/x86/kernel/sev.c
+++ b/arch/x86/kernel/sev.c
@@ -868,8 +868,7 @@ void snp_set_memory_private(unsigned long vaddr, unsigned long npages)

void snp_accept_memory(phys_addr_t start, phys_addr_t end)
{
- unsigned long vaddr;
- unsigned int npages;
+ unsigned long vaddr, npages;

if (!cc_platform_has(CC_ATTR_GUEST_SEV_SNP))
return;
--
2.40.1