From cf189c3eec014e044e50e0dfc2ee673fb703fe8c Mon Sep 17 00:00:00 2001 From: Ryan Roberts Date: Wed, 26 Feb 2025 12:16:09 +0000 Subject: [PATCH] mm: don't skip arch_sync_kernel_mappings() in error paths Fix callers that previously skipped calling arch_sync_kernel_mappings() if an error occurred during a pgtable update. The call is still required to sync any pgtable updates that may have occurred prior to hitting the error condition. These are theoretical bugs discovered during code review. Link: https://lkml.kernel.org/r/20250226121610.2401743-1-ryan.roberts@arm.com Fixes: 2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified") Fixes: 0c95cba49255 ("mm: apply_to_pte_range warn and fail if a large pte is encountered") Signed-off-by: Ryan Roberts Reviewed-by: Anshuman Khandual Reviewed-by: Catalin Marinas Cc: Christop Hellwig Cc: "Uladzislau Rezki (Sony)" Cc: Signed-off-by: Andrew Morton --- mm/memory.c | 6 ++++-- mm/vmalloc.c | 4 ++-- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index b4d3d4893267..55d0d4954627 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3051,8 +3051,10 @@ static int __apply_to_page_range(struct mm_struct *mm, unsigned long addr, next = pgd_addr_end(addr, end); if (pgd_none(*pgd) && !create) continue; - if (WARN_ON_ONCE(pgd_leaf(*pgd))) - return -EINVAL; + if (WARN_ON_ONCE(pgd_leaf(*pgd))) { + err = -EINVAL; + break; + } if (!pgd_none(*pgd) && WARN_ON_ONCE(pgd_bad(*pgd))) { if (!create) continue; diff --git a/mm/vmalloc.c b/mm/vmalloc.c index a6e7acebe9ad..61981ee1c9d2 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -586,13 +586,13 @@ static int vmap_small_pages_range_noflush(unsigned long addr, unsigned long end, mask |= PGTBL_PGD_MODIFIED; err = vmap_pages_p4d_range(pgd, addr, next, prot, pages, &nr, &mask); if (err) - return err; + break; } while (pgd++, addr = next, addr != end); if (mask & ARCH_PAGE_TABLE_SYNC_MASK) arch_sync_kernel_mappings(start, end); - return 0; + return err; } /* -- 2.50.1