From 3e03d4a1ecb83ccc74d275c2f16bd323ce2359d5 Mon Sep 17 00:00:00 2001 From: Kunwu Chan Date: Wed, 24 Apr 2024 10:53:35 +0800 Subject: [PATCH] powerpc/mm: Fix null-pointer dereference in pgtable_cache_add mainline inclusion from mainline-v6.8-rc1 commit f46c8a75263f97bda13c739ba1c90aced0d3b071 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I96GP1 CVE: CVE-2023-52607 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f46c8a75263f97bda13c739ba1c90aced0d3b071 ------------------------------------------------------ kasprintf() returns a pointer to dynamically allocated memory which can be NULL upon failure. Ensure the allocation was successful by checking the pointer validity. Suggested-by: Christophe Leroy Suggested-by: Michael Ellerman Signed-off-by: Kunwu Chan Signed-off-by: Michael Ellerman Link: https://msgid.link/20231204023223.2447523-1-chentao@kylinos.cn Signed-off-by: ZhangPeng (cherry picked from commit 22fd6183c1f1459a8e6bba2c93c7699aed57eb0f) --- arch/powerpc/mm/init-common.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/mm/init-common.c b/arch/powerpc/mm/init-common.c index 8e0d792ac296..52a20c97e46e 100644 --- a/arch/powerpc/mm/init-common.c +++ b/arch/powerpc/mm/init-common.c @@ -111,7 +111,7 @@ void pgtable_cache_add(unsigned int shift) * as to leave enough 0 bits in the address to contain it. */ unsigned long minalign = max(MAX_PGTABLE_INDEX_SIZE + 1, HUGEPD_SHIFT_MASK + 1); - struct kmem_cache *new; + struct kmem_cache *new = NULL; /* It would be nice if this was a BUILD_BUG_ON(), but at the * moment, gcc doesn't seem to recognize is_power_of_2 as a @@ -124,7 +124,8 @@ void pgtable_cache_add(unsigned int shift) align = max_t(unsigned long, align, minalign); name = kasprintf(GFP_KERNEL, "pgtable-2^%d", shift); - new = kmem_cache_create(name, table_size, align, 0, ctor(shift)); + if (name) + new = kmem_cache_create(name, table_size, align, 0, ctor(shift)); if (!new) panic("Could not allocate pgtable cache for order %d", shift); -- Gitee