6.5-stable review patch. If anyone has any objections, please let me know.
------------------
From: Tom Lendacky <thomas.lendacky@xxxxxxx>
commit 62d5e970d022ef4bde18948dd67247c3194384c1 upstream.
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. This
doesn't happen at the moment but let's be prepared.
Fixes: 6c3211796326 ("x86/sev: Add SNP-specific unaccepted memory support")
Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Cc: <stable@xxxxxxxxxx>
Link: https://lore.kernel.org/r/6d511c25576494f682063c9fb6c705b526a3757e.1687441505.git.thomas.lendacky@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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 2787826d9f60..d8c1e3be74c0 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;
--
2.42.0
