6.9-stable review patch. If anyone has any objections, please let me know.
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From: Heiko Carstens hca@linux.ibm.com
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 --- arch/s390/mm/pgalloc.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/arch/s390/mm/pgalloc.c +++ b/arch/s390/mm/pgalloc.c @@ -55,6 +55,8 @@ unsigned long *crst_table_alloc(struct m
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(un
static void base_crst_free(unsigned long *table) { + if (!table) + return; pagetable_free(virt_to_ptdesc(table)); }