--- /dev/null
+From 33d99113b1102c2d2f8603b9ba72d89d915c13f5 Mon Sep 17 00:00:00 2001
+From: Gao feng <gaofeng@cn.fujitsu.com>
+Date: Fri, 24 Jan 2014 16:29:11 +0800
+Subject: ipv6: reallocate addrconf router for ipv6 address when lo device up
+
+From: Gao feng <gaofeng@cn.fujitsu.com>
+
+commit 33d99113b1102c2d2f8603b9ba72d89d915c13f5 upstream.
+
+commit 25fb6ca4ed9cad72f14f61629b68dc03c0d9713f
+"net IPv6 : Fix broken IPv6 routing table after loopback down-up"
+allocates addrconf router for ipv6 address when lo device up.
+but commit a881ae1f625c599b460cc8f8a7fcb1c438f699ad
+"ipv6:don't call addrconf_dst_alloc again when enable lo" breaks
+this behavior.
+
+Since the addrconf router is moved to the garbage list when
+lo device down, we should release this router and rellocate
+a new one for ipv6 address when lo device up.
+
+This patch solves bug 67951 on bugzilla
+https://bugzilla.kernel.org/show_bug.cgi?id=67951
+
+change from v1:
+use ip6_rt_put to repleace ip6_del_rt, thanks Hannes!
+change code style, suggested by Sergei.
+
+CC: Sabrina Dubroca <sd@queasysnail.net>
+CC: Hannes Frederic Sowa <hannes@stressinduktion.org>
+Reported-by: Weilong Chen <chenweilong@huawei.com>
+Signed-off-by: Weilong Chen <chenweilong@huawei.com>
+Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
+Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+[weilong: s/ip6_rt_put/dst_release]
+Signed-off-by: Chen Weilong <chenweilong@huawei.com>
+Signed-off-by: Li Zefan <lizefan@huawei.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ net/ipv6/addrconf.c | 14 ++++++++++++--
+ 1 file changed, 12 insertions(+), 2 deletions(-)
+
+--- a/net/ipv6/addrconf.c
++++ b/net/ipv6/addrconf.c
+@@ -2438,8 +2438,18 @@ static void init_loopback(struct net_dev
+ if (sp_ifa->flags & (IFA_F_DADFAILED | IFA_F_TENTATIVE))
+ continue;
+
+- if (sp_ifa->rt)
+- continue;
++ if (sp_ifa->rt) {
++ /* This dst has been added to garbage list when
++ * lo device down, release this obsolete dst and
++ * reallocate a new router for ifa.
++ */
++ if (sp_ifa->rt->dst.obsolete > 0) {
++ dst_release(sp_ifa->rt);
++ sp_ifa->rt = NULL;
++ } else {
++ continue;
++ }
++ }
+
+ sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, 0);
+
--- /dev/null
+From 8e8836abf74a0b227c651cf76466b8d711470a76 Mon Sep 17 00:00:00 2001
+From: Vlastimil Babka <vbabka@suse.cz>
+Date: Mon, 7 Apr 2014 15:37:50 -0700
+Subject: mm: try_to_unmap_cluster() should lock_page() before mlocking
+
+From: Vlastimil Babka <vbabka@suse.cz>
+
+commit 57e68e9cd65b4b8eb4045a1e0d0746458502554c upstream.
+
+A BUG_ON(!PageLocked) was triggered in mlock_vma_page() by Sasha Levin
+fuzzing with trinity. The call site try_to_unmap_cluster() does not lock
+the pages other than its check_page parameter (which is already locked).
+
+The BUG_ON in mlock_vma_page() is not documented and its purpose is
+somewhat unclear, but apparently it serializes against page migration,
+which could otherwise fail to transfer the PG_mlocked flag. This would
+not be fatal, as the page would be eventually encountered again, but
+NR_MLOCK accounting would become distorted nevertheless. This patch adds
+a comment to the BUG_ON in mlock_vma_page() and munlock_vma_page() to that
+effect.
+
+The call site try_to_unmap_cluster() is fixed so that for page !=
+check_page, trylock_page() is attempted (to avoid possible deadlocks as we
+already have check_page locked) and mlock_vma_page() is performed only
+upon success. If the page lock cannot be obtained, the page is left
+without PG_mlocked, which is again not a problem in the whole unevictable
+memory design.
+
+Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
+Signed-off-by: Bob Liu <bob.liu@oracle.com>
+Reported-by: Sasha Levin <sasha.levin@oracle.com>
+Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
+Cc: Michel Lespinasse <walken@google.com>
+Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
+Acked-by: Rik van Riel <riel@redhat.com>
+Cc: David Rientjes <rientjes@google.com>
+Cc: Mel Gorman <mgorman@suse.de>
+Cc: Hugh Dickins <hughd@google.com>
+Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+[bwh: Backported to 3.2: adjust context]
+Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
+Cc: Yijing Wang <wangyijing@huawei.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ mm/mlock.c | 2 ++
+ mm/rmap.c | 14 ++++++++++++--
+ 2 files changed, 14 insertions(+), 2 deletions(-)
+
+--- a/mm/mlock.c
++++ b/mm/mlock.c
+@@ -78,6 +78,7 @@ void __clear_page_mlock(struct page *pag
+ */
+ void mlock_vma_page(struct page *page)
+ {
++ /* Serialize with page migration */
+ BUG_ON(!PageLocked(page));
+
+ if (!TestSetPageMlocked(page)) {
+@@ -105,6 +106,7 @@ void mlock_vma_page(struct page *page)
+ */
+ void munlock_vma_page(struct page *page)
+ {
++ /* For try_to_munlock() and to serialize with page migration */
+ BUG_ON(!PageLocked(page));
+
+ if (TestClearPageMlocked(page)) {
+--- a/mm/rmap.c
++++ b/mm/rmap.c
+@@ -1449,9 +1449,19 @@ static int try_to_unmap_cluster(unsigned
+ BUG_ON(!page || PageAnon(page));
+
+ if (locked_vma) {
+- mlock_vma_page(page); /* no-op if already mlocked */
+- if (page == check_page)
++ if (page == check_page) {
++ /* we know we have check_page locked */
++ mlock_vma_page(page);
+ ret = SWAP_MLOCK;
++ } else if (trylock_page(page)) {
++ /*
++ * If we can lock the page, perform mlock.
++ * Otherwise leave the page alone, it will be
++ * eventually encountered again later.
++ */
++ mlock_vma_page(page);
++ unlock_page(page);
++ }
+ continue; /* don't unmap */
+ }
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
