diff options
| author | Heiko Carstens <hca@linux.ibm.com> | 2024-07-09 08:50:56 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-07-18 13:22:47 +0200 |
| commit | f80bd8bb6f380bc265834c46058d38b34174813e (patch) | |
| tree | 5188f8a0655422faf07a018e2009712635219d62 | |
| parent | ef16ae2e2dfdd09dc919bf946c1c217c61e0bebe (diff) | |
s390/mm: Add NULL pointer check to crst_table_free() base_crst_free()
commit b5efb63acf7bddaf20eacfcac654c25c446eabe8 upstream.
crst_table_free() used to work with NULL pointers before the conversion
to ptdescs. Since crst_table_free() can be called with a NULL pointer
(error handling in crst_table_upgrade() add an explicit check.
Also add the same check to base_crst_free() for consistency reasons.
In real life this should not happen, since order two GFP_KERNEL
allocations will not fail, unless FAIL_PAGE_ALLOC is enabled and used.
Reported-by: Yunseong Kim <yskelg@gmail.com>
Fixes: 6326c26c1514 ("s390: convert various pgalloc functions to use ptdescs")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/s390/mm/pgalloc.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c index abb629d7e131..7e3e767ab87d 100644 --- a/arch/s390/mm/pgalloc.c +++ b/arch/s390/mm/pgalloc.c @@ -55,6 +55,8 @@ unsigned long *crst_table_alloc(struct mm_struct *mm) void crst_table_free(struct mm_struct *mm, unsigned long *table) { + if (!table) + return; pagetable_free(virt_to_ptdesc(table)); } @@ -262,6 +264,8 @@ static unsigned long *base_crst_alloc(unsigned long val) static void base_crst_free(unsigned long *table) { + if (!table) + return; pagetable_free(virt_to_ptdesc(table)); } |