[PATCH] LoongArch: vDSO: check kcalloc() result in init_vdso

[lgs201920130244]

From: Guangshuo Li <202321181@xxxxxxxxxxxxxxx>

Add a NULL-pointer check after the kcalloc() call in init_vdso(). If
allocation fails, return -ENOMEM to prevent a possible dereference of
vdso_info.code_mapping.pages when it is NULL.

Fixes: 2ed119aef60d ("LoongArch: Set correct size for vDSO code mapping")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Guangshuo Li <202321181@xxxxxxxxxxxxxxx>
---
 arch/loongarch/kernel/vdso.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/loongarch/kernel/vdso.c b/arch/loongarch/kernel/vdso.c
index 10cf1608c7b3..da7a7922fb24 100644
--- a/arch/loongarch/kernel/vdso.c
+++ b/arch/loongarch/kernel/vdso.c
@@ -53,7 +53,8 @@ static int __init init_vdso(void)
 	vdso_info.size = PAGE_ALIGN(vdso_end - vdso_start);
 	vdso_info.code_mapping.pages =
 		kcalloc(vdso_info.size / PAGE_SIZE, sizeof(struct page *), GFP_KERNEL);
-
+	if (!vdso_info.code_mapping.pages)
+		return -ENOMEM;
 	pfn = __phys_to_pfn(__pa_symbol(vdso_info.vdso));
 	for (i = 0; i < vdso_info.size / PAGE_SIZE; i++)
 		vdso_info.code_mapping.pages[i] = pfn_to_page(pfn + i);
-- 
2.43.0