Merge https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 1c0f3e02f731..ca692a815731 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1444,11 +1444,28 @@ static void __remove_pgd_mapping(pgd_t *pgdir, unsigned long start, u64 size)
 	free_empty_tables(start, end, PAGE_OFFSET, PAGE_END);
 }
 
+static bool inside_linear_region(u64 start, u64 size)
+{
+	/*
+	 * Linear mapping region is the range [PAGE_OFFSET..(PAGE_END - 1)]
+	 * accommodating both its ends but excluding PAGE_END. Max physical
+	 * range which can be mapped inside this linear mapping range, must
+	 * also be derived from its end points.
+	 */
+	return start >= __pa(_PAGE_OFFSET(vabits_actual)) &&
+	       (start + size - 1) <= __pa(PAGE_END - 1);
+}
+
 int arch_add_memory(int nid, u64 start, u64 size,
 		    struct mhp_params *params)
 {
 	int ret, flags = 0;
 
+	if (!inside_linear_region(start, size)) {
+		pr_err("[%llx %llx] is outside linear mapping region\n", start, start + size);
+		return -EINVAL;
+	}
+
 	if (rodata_full || debug_pagealloc_enabled())
 		flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;