[PATCH] powerpc/mm: Fix null-pointer dereference in pgtable_cache_add

From: Kunwu Chan
Date: Wed Nov 22 2023 - 04:00:51 EST


kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure. Ensure the allocation was successful
by checking the pointer validity.

Signed-off-by: Kunwu Chan <chentao@xxxxxxxxxx>
---
arch/powerpc/mm/init-common.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/mm/init-common.c b/arch/powerpc/mm/init-common.c
index 119ef491f797..0884fc601c46 100644
--- a/arch/powerpc/mm/init-common.c
+++ b/arch/powerpc/mm/init-common.c
@@ -139,6 +139,8 @@ void pgtable_cache_add(unsigned int shift)

align = max_t(unsigned long, align, minalign);
name = kasprintf(GFP_KERNEL, "pgtable-2^%d", shift);
+ if (!name)
+ return;
new = kmem_cache_create(name, table_size, align, 0, ctor(shift));
if (!new)
panic("Could not allocate pgtable cache for order %d", shift);
--
2.34.1