sync mm-stable with mm-hotfixes-stable to pick up depended-upon upstream changes

2 files changed, 65 insertions, 17 deletions

diff --git a/mm/kmsan/hooks.c b/mm/kmsan/hooks.c
index 3807502766a3..ec0da72e65aa 100644
--- a/mm/kmsan/hooks.c
+++ b/mm/kmsan/hooks.c
@@ -148,35 +148,74 @@ void kmsan_vunmap_range_noflush(unsigned long start, unsigned long end)
  * into the virtual memory. If those physical pages already had shadow/origin,
  * those are ignored.
  */
-void kmsan_ioremap_page_range(unsigned long start, unsigned long end,
-			      phys_addr_t phys_addr, pgprot_t prot,
-			      unsigned int page_shift)
+int kmsan_ioremap_page_range(unsigned long start, unsigned long end,
+			     phys_addr_t phys_addr, pgprot_t prot,
+			     unsigned int page_shift)
 {
 	gfp_t gfp_mask = GFP_KERNEL | __GFP_ZERO;
 	struct page *shadow, *origin;
 	unsigned long off = 0;
-	int nr;
+	int nr, err = 0, clean = 0, mapped;
 
 	if (!kmsan_enabled || kmsan_in_runtime())
-		return;
+		return 0;
 
 	nr = (end - start) / PAGE_SIZE;
 	kmsan_enter_runtime();
-	for (int i = 0; i < nr; i++, off += PAGE_SIZE) {
+	for (int i = 0; i < nr; i++, off += PAGE_SIZE, clean = i) {
 		shadow = alloc_pages(gfp_mask, 1);
 		origin = alloc_pages(gfp_mask, 1);
-		__vmap_pages_range_noflush(
+		if (!shadow || !origin) {
+			err = -ENOMEM;
+			goto ret;
+		}
+		mapped = __vmap_pages_range_noflush(
 			vmalloc_shadow(start + off),
 			vmalloc_shadow(start + off + PAGE_SIZE), prot, &shadow,
 			PAGE_SHIFT);
-		__vmap_pages_range_noflush(
+		if (mapped) {
+			err = mapped;
+			goto ret;
+		}
+		shadow = NULL;
+		mapped = __vmap_pages_range_noflush(
 			vmalloc_origin(start + off),
 			vmalloc_origin(start + off + PAGE_SIZE), prot, &origin,
 			PAGE_SHIFT);
+		if (mapped) {
+			__vunmap_range_noflush(
+				vmalloc_shadow(start + off),
+				vmalloc_shadow(start + off + PAGE_SIZE));
+			err = mapped;
+			goto ret;
+		}
+		origin = NULL;
+	}
+	/* Page mapping loop finished normally, nothing to clean up. */
+	clean = 0;
+
+ret:
+	if (clean > 0) {
+		/*
+		 * Something went wrong. Clean up shadow/origin pages allocated
+		 * on the last loop iteration, then delete mappings created
+		 * during the previous iterations.
+		 */
+		if (shadow)
+			__free_pages(shadow, 1);
+		if (origin)
+			__free_pages(origin, 1);
+		__vunmap_range_noflush(
+			vmalloc_shadow(start),
+			vmalloc_shadow(start + clean * PAGE_SIZE));
+		__vunmap_range_noflush(
+			vmalloc_origin(start),
+			vmalloc_origin(start + clean * PAGE_SIZE));
 	}
 	flush_cache_vmap(vmalloc_shadow(start), vmalloc_shadow(end));
 	flush_cache_vmap(vmalloc_origin(start), vmalloc_origin(end));
 	kmsan_leave_runtime();
+	return err;
 }
 
 void kmsan_iounmap_page_range(unsigned long start, unsigned long end)
diff --git a/mm/kmsan/shadow.c b/mm/kmsan/shadow.c
index a787c04e9583..b8bb95eea5e3 100644
--- a/mm/kmsan/shadow.c
+++ b/mm/kmsan/shadow.c
@@ -216,27 +216,29 @@ void kmsan_free_page(struct page *page, unsigned int order)
 	kmsan_leave_runtime();
 }
 
-void kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end,
-				    pgprot_t prot, struct page **pages,
-				    unsigned int page_shift)
+int kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end,
+				   pgprot_t prot, struct page **pages,
+				   unsigned int page_shift)
 {
 	unsigned long shadow_start, origin_start, shadow_end, origin_end;
 	struct page **s_pages, **o_pages;
-	int nr, mapped;
+	int nr, mapped, err = 0;
 
 	if (!kmsan_enabled)
-		return;
+		return 0;
 
 	shadow_start = vmalloc_meta((void *)start, KMSAN_META_SHADOW);
 	shadow_end = vmalloc_meta((void *)end, KMSAN_META_SHADOW);
 	if (!shadow_start)
-		return;
+		return 0;
 
 	nr = (end - start) / PAGE_SIZE;
 	s_pages = kcalloc(nr, sizeof(*s_pages), GFP_KERNEL);
 	o_pages = kcalloc(nr, sizeof(*o_pages), GFP_KERNEL);
-	if (!s_pages || !o_pages)
+	if (!s_pages || !o_pages) {
+		err = -ENOMEM;
 		goto ret;
+	}
 	for (int i = 0; i < nr; i++) {
 		s_pages[i] = shadow_page_for(pages[i]);
 		o_pages[i] = origin_page_for(pages[i]);
@@ -249,10 +251,16 @@ void kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end,
 	kmsan_enter_runtime();
 	mapped = __vmap_pages_range_noflush(shadow_start, shadow_end, prot,
 					    s_pages, page_shift);
-	KMSAN_WARN_ON(mapped);
+	if (mapped) {
+		err = mapped;
+		goto ret;
+	}
 	mapped = __vmap_pages_range_noflush(origin_start, origin_end, prot,
 					    o_pages, page_shift);
-	KMSAN_WARN_ON(mapped);
+	if (mapped) {
+		err = mapped;
+		goto ret;
+	}
 	kmsan_leave_runtime();
 	flush_tlb_kernel_range(shadow_start, shadow_end);
 	flush_tlb_kernel_range(origin_start, origin_end);
@@ -262,6 +270,7 @@ void kmsan_vmap_pages_range_noflush(unsigned long start, unsigned long end,
 ret:
 	kfree(s_pages);
 	kfree(o_pages);
+	return err;
 }
 
 /* Allocate metadata for pages allocated at boot time. */