4.19-stable patches

added patches:
	memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch

diff --git a/queue-4.19/memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch b/queue-4.19/memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch
new file mode 100644 (file)
index 0000000..a6af83c
--- /dev/null
+++ b/queue-4.19/memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch
@@ -0,0 +1,38 @@
+From zhongjiang@huawei.com  Tue Nov 19 05:56:14 2019
+From: zhong jiang <zhongjiang@huawei.com>
+Date: Mon, 18 Nov 2019 11:26:08 +0800
+Subject: memfd: Use radix_tree_deref_slot_protected to avoid the warning.
+To: <sashal@kernel.org>, <gregkh@linuxfoundation.org>, <stable@vger.kernel.org>, <willy@infradead.org>
+Cc: <linux-mm@kvack.org>, <yangyingliang@huawei.com>
+Message-ID: <20191118032610.182862-2-zhongjiang@huawei.com>
+
+From: zhong jiang <zhongjiang@huawei.com>
+
+The commit 99b45e7a1ba1 ("memfd: Fix locking when tagging pins")
+introduces the following warning messages.
+
+*WARNING: suspicious RCU usage in memfd_wait_for_pins*
+
+It is because we still use radix_tree_deref_slot without read_rcu_lock.
+We should use radix_tree_deref_slot_protected instead in the case.
+
+Cc: stable@vger.kernel.org
+Fixes: 99b45e7a1ba1 ("memfd: Fix locking when tagging pins")
+Signed-off-by: zhong jiang <zhongjiang@huawei.com>
+Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ mm/memfd.c |    2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/mm/memfd.c
++++ b/mm/memfd.c
+@@ -41,7 +41,7 @@ static void memfd_tag_pins(struct addres
+ 
+       xa_lock_irq(&mapping->i_pages);
+       radix_tree_for_each_slot(slot, &mapping->i_pages, &iter, start) {
+-              page = radix_tree_deref_slot(slot);
++              page = radix_tree_deref_slot_protected(slot, &mapping->i_pages.xa_lock);
+               if (!page || radix_tree_exception(page)) {
+                       if (radix_tree_deref_retry(page)) {
+                               slot = radix_tree_iter_retry(&iter);

diff --git a/queue-4.19/series b/queue-4.19/series
index ba0f31751c32e4add32103558adf3a5b1c0d3e61..9d0ff425bc3a8fa1a5d634b4ee6ed34c9e3392af 100644 (file)
--- a/queue-4.19/series
+++ b/queue-4.19/series
@@ -420,3 +420,4 @@ ib-iser-fix-possible-null-deref-at-iser_inv_desc.patch
 media-ov2680-fix-null-dereference-at-power-on.patch
 s390-vdso-correct-vdso-mapping-for-compat-tasks.patch
 net-phy-mdio-bcm-unimac-mark-pm-functions-as-__maybe.patch
+memfd-use-radix_tree_deref_slot_protected-to-avoid-the-warning.patch