5.12.13-rc1 review

From: Nikolay Aleksandrov <[email protected]>

commit cfc579f9d89af4ada58c69b03bcaa4887840f3b3 upstream.

The egress tunnel code uses dst_clone() and directly sets the result which is wrong because the entry might have 0 refcnt or be already deleted, causing number of problems. It also triggers the WARN_ON() in dst_hold()[1] when a refcnt couldn't be taken. Fix it by using dst_hold_safe() and checking if a reference was actually taken before setting the dst.

[1] dmesg WARN_ON log and following refcnt errors

 WARNING: CPU: 5 PID: 38 at include/net/dst.h:230 br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]
 Modules linked in: 8021q garp mrp bridge stp llc bonding ipv6 virtio_net
 CPU: 5 PID: 38 Comm: ksoftirqd/5 Kdump: loaded Tainted: G        W         5.13.0-rc3+ #360
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
 RIP: 0010:br_handle_egress_vlan_tunnel+0x10b/0x134 [bridge]
 Code: e8 85 bc 01 e1 45 84 f6 74 90 45 31 f6 85 db 48 c7 c7 a0 02 19 a0 41 0f 94 c6 31 c9 31 d2 44 89 f6 e8 64 bc 01 e1 85 db 75 02 <0f> 0b 31 c9 31 d2 44 89 f6 48 c7 c7 70 02 19 a0 e8 4b bc 01 e1 49
 RSP: 0018:ffff8881003d39e8 EFLAGS: 00010246
 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffffa01902a0
 RBP: ffff8881040c6700 R08: 0000000000000000 R09: 0000000000000001
 R10: 2ce93d0054fe0d00 R11: 54fe0d00000e0000 R12: ffff888109515000
 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000401
 FS:  0000000000000000(0000) GS:ffff88822bf40000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007f42ba70f030 CR3: 0000000109926000 CR4: 00000000000006e0
 Call Trace:
  br_handle_vlan+0xbc/0xca [bridge]
  __br_forward+0x23/0x164 [bridge]
  deliver_clone+0x41/0x48 [bridge]
  br_handle_frame_finish+0x36f/0x3aa [bridge]
  ? skb_dst+0x2e/0x38 [bridge]
  ? br_handle_ingress_vlan_tunnel+0x3e/0x1c8 [bridge]
  ? br_handle_frame_finish+0x3aa/0x3aa [bridge]
  br_handle_frame+0x2c3/0x377 [bridge]
  ? __skb_pull+0x33/0x51
  ? vlan_do_receive+0x4f/0x36a
  ? br_handle_frame_finish+0x3aa/0x3aa [bridge]
  __netif_receive_skb_core+0x539/0x7c6
  ? __list_del_entry_valid+0x16e/0x1c2
  __netif_receive_skb_list_core+0x6d/0xd6
  netif_receive_skb_list_internal+0x1d9/0x1fa
  gro_normal_list+0x22/0x3e
  dev_gro_receive+0x55b/0x600
  ? detach_buf_split+0x58/0x140
  napi_gro_receive+0x94/0x12e
  virtnet_poll+0x15d/0x315 [virtio_net]
  __napi_poll+0x2c/0x1c9
  net_rx_action+0xe6/0x1fb
  __do_softirq+0x115/0x2d8
  run_ksoftirqd+0x18/0x20
  smpboot_thread_fn+0x183/0x19c
  ? smpboot_unregister_percpu_thread+0x66/0x66
  kthread+0x10a/0x10f
  ? kthread_mod_delayed_work+0xb6/0xb6
  ret_from_fork+0x22/0x30
 ---[ end trace 49f61b07f775fd2b ]---
 dst_release: dst:00000000c02d677a refcnt:-1
 dst_release underflow

---
 net/bridge/br_vlan_tunnel.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -204,8 +204,8 @@ int br_handle_egress_vlan_tunnel(struct
 		return err;
 
 	tunnel_dst = rcu_dereference(vlan->tinfo.tunnel_dst);
-	if (tunnel_dst)
-		skb_dst_set(skb, dst_clone(&tunnel_dst->dst));
+	if (tunnel_dst && dst_hold_safe(&tunnel_dst->dst))
+		skb_dst_set(skb, &tunnel_dst->dst);
 
 	return 0;
 }

From: Naoya Horiguchi <[email protected]>

commit 25182f05ffed0b45602438693e4eed5d7f3ebadd upstream.

When hugetlb page fault (under overcommitting situation) and memory_failure() race, VM_BUG_ON_PAGE() is triggered by the following race:

CPU0: CPU1:

gather_surplus_pages()
page = alloc_surplus_huge_page()
memory_failure_hugetlb()
get_hwpoison_page(page)
__get_hwpoison_page(page)
get_page_unless_zero(page)
zero = put_page_testzero(page) VM_BUG_ON_PAGE(!zero, page) enqueue_huge_page(h, page)
put_page(page)

__get_hwpoison_page() only checks the page refcount before taking an additional one for memory error handling, which is not enough because there's a time window where compound pages have non-zero refcount during hugetlb page initialization.

So make __get_hwpoison_page() check page status a bit more for hugetlb pages with get_hwpoison_huge_page(). Checking hugetlb-specific flags under hugetlb_lock makes sure that the hugetlb page is not transitive. It's notable that another new function, HWPoisonHandlable(), is helpful to prevent a race against other transitive page states (like a generic compound page just before PageHuge becomes true).

---
 include/linux/hugetlb.h |    6 ++++++
 mm/hugetlb.c            |   15 +++++++++++++++
 mm/memory-failure.c     |   29 +++++++++++++++++++++++++++--
 3 files changed, 48 insertions(+), 2 deletions(-)

@@ -145,6 +145,7 @@ bool hugetlb_reserve_pages(struct inode
 long hugetlb_unreserve_pages(struct inode *inode, long start, long end,
 						long freed);
 bool isolate_huge_page(struct page *page, struct list_head *list);
+int get_hwpoison_huge_page(struct page *page, bool *hugetlb);
 void putback_active_hugepage(struct page *page);
 void move_hugetlb_state(struct page *oldpage, struct page *newpage, int reason);
 void free_huge_page(struct page *page);

@@ -330,6 +331,11 @@ static inline bool isolate_huge_page(str
 	return false;
 }
 
+static inline int get_hwpoison_huge_page(struct page *page, bool *hugetlb)
+{
+	return 0;
+}
+
 static inline void putback_active_hugepage(struct page *page)
 {
 }

@@ -5664,6 +5664,21 @@ unlock:
 	return ret;
 }
 
+int get_hwpoison_huge_page(struct page *page, bool *hugetlb)
+{
+	int ret = 0;
+
+	*hugetlb = false;
+	spin_lock_irq(&hugetlb_lock);
+	if (PageHeadHuge(page)) {
+		*hugetlb = true;
+		if (HPageFreed(page) || HPageMigratable(page))
+			ret = get_page_unless_zero(page);
+	}
+	spin_unlock_irq(&hugetlb_lock);
+	return ret;
+}
+
 void putback_active_hugepage(struct page *page)
 {
 	spin_lock(&hugetlb_lock);

@@ -949,6 +949,17 @@ static int page_action(struct page_state
 	return (result == MF_RECOVERED || result == MF_DELAYED) ? 0 : -EBUSY;
 }
 
+/*
+ * Return true if a page type of a given page is supported by hwpoison
+ * mechanism (while handling could fail), otherwise false.  This function
+ * does not return true for hugetlb or device memory pages, so it's assumed
+ * to be called only in the context where we never have such pages.
+ */
+static inline bool HWPoisonHandlable(struct page *page)
+{
+	return PageLRU(page) || __PageMovable(page);
+}
+
 /**
  * __get_hwpoison_page() - Get refcount for memory error handling:
  * @page:	raw error page (hit by memory error)

@@ -959,8 +970,22 @@ static int page_action(struct page_state
 static int __get_hwpoison_page(struct page *page)
 {
 	struct page *head = compound_head(page);
+	int ret = 0;
+	bool hugetlb = false;
+
+	ret = get_hwpoison_huge_page(head, &hugetlb);
+	if (hugetlb)
+		return ret;
+
+	/*
+	 * This check prevents from calling get_hwpoison_unless_zero()
+	 * for any unsupported type of page in order to reduce the risk of
+	 * unexpected races caused by taking a page refcount.
+	 */
+	if (!HWPoisonHandlable(head))
+		return 0;
 
-	if (!PageHuge(head) && PageTransHuge(head)) {
+	if (PageTransHuge(head)) {
 		/*
 		 * Non anonymous thp exists only in allocation/free time. We
 		 * can't handle such a case correctly, so let's give it up.

@@ -1017,7 +1042,7 @@ try_again:
 			ret = -EIO;
 		}
 	} else {
-		if (PageHuge(p) || PageLRU(p) || __PageMovable(p)) {
+		if (PageHuge(p) || HWPoisonHandlable(p)) {
 			ret = 1;
 		} else {
 			/*

From: Peter Xu <[email protected]>

commit 099dd6878b9b12d6bbfa6bf29ce0c8ddd38f6901 upstream.

I found it by pure code review, that pte_same_as_swp() of unuse_vma() didn't take uffd-wp bit into account when comparing ptes. pte_same_as_swp() returning false negative could cause failure to swapoff swap ptes that was wr-protected by userfaultfd.

---
 include/linux/swapops.h |   15 +++++++++++----
 mm/swapfile.c           |    2 +-
 2 files changed, 12 insertions(+), 5 deletions(-)

@@ -23,6 +23,16 @@
 #define SWP_TYPE_SHIFT	(BITS_PER_XA_VALUE - MAX_SWAPFILES_SHIFT)
 #define SWP_OFFSET_MASK	((1UL << SWP_TYPE_SHIFT) - 1)
 
+/* Clear all flags but only keep swp_entry_t related information */
+static inline pte_t pte_swp_clear_flags(pte_t pte)
+{
+	if (pte_swp_soft_dirty(pte))
+		pte = pte_swp_clear_soft_dirty(pte);
+	if (pte_swp_uffd_wp(pte))
+		pte = pte_swp_clear_uffd_wp(pte);
+	return pte;
+}
+
 /*
  * Store a type+offset into a swp_entry_t in an arch-independent format
  */

@@ -66,10 +76,7 @@ static inline swp_entry_t pte_to_swp_ent
 {
 	swp_entry_t arch_entry;
 
-	if (pte_swp_soft_dirty(pte))
-		pte = pte_swp_clear_soft_dirty(pte);
-	if (pte_swp_uffd_wp(pte))
-		pte = pte_swp_clear_uffd_wp(pte);
+	pte = pte_swp_clear_flags(pte);
 	arch_entry = __pte_to_swp_entry(pte);
 	return swp_entry(__swp_type(arch_entry), __swp_offset(arch_entry));
 }

@@ -1900,7 +1900,7 @@ unsigned int count_swap_pages(int type,
 
 static inline int pte_same_as_swp(pte_t pte, pte_t swp_pte)
 {
-	return pte_same(pte_swp_clear_soft_dirty(pte), swp_pte);
+	return pte_same(pte_swp_clear_flags(pte), swp_pte);
 }
 
 /*

From: Mike Kravetz <[email protected]>

commit 846be08578edb81f02bc8534577e6c367ef34f41 upstream.

The routine restore_reserve_on_error is called to restore reservation information when an error occurs after page allocation. The routine alloc_huge_page modifies the mapping reserve map and potentially the reserve count during allocation. If code calling alloc_huge_page encounters an error after allocation and needs to free the page, the reservation information needs to be adjusted.

Currently, restore_reserve_on_error only takes action on pages for which the reserve count was adjusted(HPageRestoreReserve flag). There is nothing wrong with these adjustments. However, alloc_huge_page ALWAYS modifies the reserve map during allocation even if the reserve count is not adjusted. This can cause issues as observed during development of this patch [1].

One specific series of operations causing an issue is:

- Create a shared hugetlb mapping
Reservations for all pages created by default

- Fault in a page in the mapping
Reservation exists so reservation count is decremented

- Punch a hole in the file/mapping at index previously faulted Reservation and any associated pages will be removed

- Allocate a page to fill the hole
No reservation entry, so reserve count unmodified Reservation entry added to map by alloc_huge_page

- Error after allocation and before instantiating the page Reservation entry remains in map

- Allocate a page to fill the hole
Reservation entry exists, so decrement reservation count

This will cause a reservation count underflow as the reservation count was decremented twice for the same index.

A user would observe a very large number for HugePages_Rsvd in /proc/meminfo. This would also likely cause subsequent allocations of hugetlb pages to fail as it would 'appear' that all pages are reserved.

This sequence of operations is unlikely to happen, however they were easily reproduced and observed using hacked up code as described in [1].

Address the issue by having the routine restore_reserve_on_error take action on pages where HPageRestoreReserve is not set. In this case, we need to remove any reserve map entry created by alloc_huge_page. A new helper routine vma_del_reservation assists with this operation.

There are three callers of alloc_huge_page which do not currently call restore_reserve_on error before freeing a page on error paths. Add those missing calls.

[1] https://lore.kernel.org/linux-mm/[email protected]/

---
 fs/hugetlbfs/inode.c    |    1 
 include/linux/hugetlb.h |    2 
 mm/hugetlb.c            |  120 ++++++++++++++++++++++++++++++++++++++----------
 3 files changed, 100 insertions(+), 23 deletions(-)

@@ -738,6 +738,7 @@ static long hugetlbfs_fallocate(struct f
 		__SetPageUptodate(page);
 		error = huge_add_to_page_cache(page, mapping, index);
 		if (unlikely(error)) {
+			restore_reserve_on_error(h, &pseudo_vma, addr, page);
 			put_page(page);
 			mutex_unlock(&hugetlb_fault_mutex_table[hash]);
 			goto out;

@@ -597,6 +597,8 @@ struct page *alloc_huge_page_vma(struct
 				unsigned long address);
 int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
 			pgoff_t idx);
+void restore_reserve_on_error(struct hstate *h, struct vm_area_struct *vma,
+				unsigned long address, struct page *page);
 
 /* arch callback */
 int __init __alloc_bootmem_huge_page(struct hstate *h);

From: Kees Cook <[email protected]>

commit 8669dbab2ae56085c128894b181c2aa50f97e368 upstream.

Patch series "Actually fix freelist pointer vs redzoning", v4.

This fixes redzoning vs the freelist pointer (both for middle-position and very small caches). Both are "theoretical" fixes, in that I see no evidence of such small-sized caches actually be used in the kernel, but that's no reason to let the bugs continue to exist, especially since people doing local development keep tripping over it. :)

This patch (of 3):

Instead of repeating "Redzone" and "Poison", clarify which sides of those zones got tripped. Additionally fix column alignment in the trailer.

Before:

BUG test (Tainted: G B ): Redzone overwritten
...
Redzone (____ptrval____): bb bb bb bb bb bb bb bb ........
Object (____ptrval____): f6 f4 a5 40 1d e8 ...@..
Redzone (____ptrval____): 1a aa ..
Padding (____ptrval____): 00 00 00 00 00 00 00 00 ........

After:

BUG test (Tainted: G B ): Right Redzone overwritten
...

  Redzone  (____ptrval____): bb bb bb bb bb bb bb bb      ........
  Object   (____ptrval____): f6 f4 a5 40 1d e8            ...@..
  Redzone  (____ptrval____): 1a aa                        ..
  Padding  (____ptrval____): 00 00 00 00 00 00 00 00      ........

The earlier commits that slowly resulted in the "Before" reporting were:

d86bd1bece6f ("mm/slub: support left redzone")
ffc79d288000 ("slub: use print_hex_dump")
2492268472e7 ("SLUB: change error reporting format to follow lockdep loosely")

---
 Documentation/vm/slub.rst |   10 +++++-----
 mm/slub.c                 |   14 +++++++-------
 2 files changed, 12 insertions(+), 12 deletions(-)

@@ -181,7 +181,7 @@ SLUB Debug output
 Here is a sample of slub debug output::
 
  ====================================================================
- BUG kmalloc-8: Redzone overwritten
+ BUG kmalloc-8: Right Redzone overwritten
  --------------------------------------------------------------------
 
  INFO: 0xc90f6d28-0xc90f6d2b. First byte 0x00 instead of 0xcc

@@ -189,10 +189,10 @@ Here is a sample of slub debug output::
  INFO: Object 0xc90f6d20 @offset=3360 fp=0xc90f6d58
  INFO: Allocated in get_modalias+0x61/0xf5 age=53 cpu=1 pid=554
 
- Bytes b4 0xc90f6d10:  00 00 00 00 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a ........ZZZZZZZZ
-   Object 0xc90f6d20:  31 30 31 39 2e 30 30 35                         1019.005
-  Redzone 0xc90f6d28:  00 cc cc cc                                     .
-  Padding 0xc90f6d50:  5a 5a 5a 5a 5a 5a 5a 5a                         ZZZZZZZZ
+ Bytes b4 (0xc90f6d10): 00 00 00 00 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a ........ZZZZZZZZ
+ Object   (0xc90f6d20): 31 30 31 39 2e 30 30 35                         1019.005
+ Redzone  (0xc90f6d28): 00 cc cc cc                                     .
+ Padding  (0xc90f6d50): 5a 5a 5a 5a 5a 5a 5a 5a                         ZZZZZZZZ
 
    [<c010523d>] dump_trace+0x63/0x1eb
    [<c01053df>] show_trace_log_lvl+0x1a/0x2f

@@ -710,15 +710,15 @@ static void print_trailer(struct kmem_ca
 	       p, p - addr, get_freepointer(s, p));
 
 	if (s->flags & SLAB_RED_ZONE)
-		print_section(KERN_ERR, "Redzone ", p - s->red_left_pad,
+		print_section(KERN_ERR, "Redzone  ", p - s->red_left_pad,
 			      s->red_left_pad);
 	else if (p > addr + 16)
 		print_section(KERN_ERR, "Bytes b4 ", p - 16, 16);
 
-	print_section(KERN_ERR, "Object ", p,
+	print_section(KERN_ERR,         "Object   ", p,
 		      min_t(unsigned int, s->object_size, PAGE_SIZE));
 	if (s->flags & SLAB_RED_ZONE)
-		print_section(KERN_ERR, "Redzone ", p + s->object_size,
+		print_section(KERN_ERR, "Redzone  ", p + s->object_size,
 			s->inuse - s->object_size);
 
 	off = get_info_end(s);

@@ -730,7 +730,7 @@ static void print_trailer(struct kmem_ca
 
 	if (off != size_from_object(s))
 		/* Beginning of the filler is the free pointer */
-		print_section(KERN_ERR, "Padding ", p + off,
+		print_section(KERN_ERR, "Padding  ", p + off,
 			      size_from_object(s) - off);
 
 	dump_stack();

@@ -907,11 +907,11 @@ static int check_object(struct kmem_cach
 	u8 *endobject = object + s->object_size;
 
 	if (s->flags & SLAB_RED_ZONE) {
-		if (!check_bytes_and_report(s, page, object, "Redzone",
+		if (!check_bytes_and_report(s, page, object, "Left Redzone",
 			object - s->red_left_pad, val, s->red_left_pad))
 			return 0;
 
-		if (!check_bytes_and_report(s, page, object, "Redzone",
+		if (!check_bytes_and_report(s, page, object, "Right Redzone",
 			endobject, val, s->inuse - s->object_size))
 			return 0;
 	} else {

@@ -926,7 +926,7 @@ static int check_object(struct kmem_cach
 		if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) &&
 			(!check_bytes_and_report(s, page, p, "Poison", p,
 					POISON_FREE, s->object_size - 1) ||
-			 !check_bytes_and_report(s, page, p, "Poison",
+			 !check_bytes_and_report(s, page, p, "End Poison",
 				p + s->object_size - 1, POISON_END, 1)))
 			return 0;
 		/*

From: Kees Cook <[email protected]>

commit 74c1d3e081533825f2611e46edea1fcdc0701985 upstream.

The redzone area for SLUB exists between s->object_size and s->inuse (which is at least the word-aligned object_size). If a cache were created with an object_size smaller than sizeof(void *), the in-object stored freelist pointer would overwrite the redzone (e.g. with boot param "slub_debug=ZF"):

BUG test (Tainted: G B ): Right Redzone overwritten
-----------------------------------------------------------------------------

INFO: 0xffff957ead1c05de-0xffff957ead1c05df @offset=1502. First byte 0x1a instead of 0xbb
INFO: Slab 0xffffef3950b47000 objects=170 used=170 fp=0x0000000000000000 flags=0x8000000000000200
INFO: Object 0xffff957ead1c05d8 @offset=1496 fp=0xffff957ead1c0620

  Redzone  (____ptrval____): bb bb bb bb bb bb bb bb    ........
  Object   (____ptrval____): f6 f4 a5 40 1d e8          ...@..
  Redzone  (____ptrval____): 1a aa                      ..
  Padding  (____ptrval____): 00 00 00 00 00 00 00 00    ........

Store the freelist pointer out of line when object_size is smaller than sizeof(void *) and redzoning is enabled.

Additionally remove the "smaller than sizeof(void *)" check under CONFIG_DEBUG_VM in kmem_cache_sanity_check() as it is now redundant:
SLAB and SLOB both handle small sizes.

(Note that no caches within this size range are known to exist in the kernel currently.)

---
 mm/slab_common.c |    3 +--
 mm/slub.c        |    8 +++++---
 2 files changed, 6 insertions(+), 5 deletions(-)

@@ -89,8 +89,7 @@ EXPORT_SYMBOL(kmem_cache_size);
 #ifdef CONFIG_DEBUG_VM
 static int kmem_cache_sanity_check(const char *name, unsigned int size)
 {
-	if (!name || in_interrupt() || size < sizeof(void *) ||
-		size > KMALLOC_MAX_SIZE) {
+	if (!name || in_interrupt() || size > KMALLOC_MAX_SIZE) {
 		pr_err("kmem_cache_create(%s) integrity check failed\n", name);
 		return -EINVAL;
 	}

@@ -3732,15 +3732,17 @@ static int calculate_sizes(struct kmem_c
 	 */
 	s->inuse = size;
 
-	if (((flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) ||
-		s->ctor)) {
+	if ((flags & (SLAB_TYPESAFE_BY_RCU | SLAB_POISON)) ||
+	    ((flags & SLAB_RED_ZONE) && s->object_size < sizeof(void *)) ||
+	    s->ctor) {
 		/*
 		 * Relocate free pointer after the object if it is not
 		 * permitted to overwrite the first word of the object on
 		 * kmem_cache_free.
 		 *
 		 * This is the case if we do RCU, have a constructor or
-		 * destructor or are poisoning the objects.
+		 * destructor, are poisoning the objects, or are
+		 * redzoning an object smaller than sizeof(void *).
 		 *
 		 * The assumption that s->offset >= s->inuse means free
 		 * pointer is outside of the object is used in the

From: Kees Cook <[email protected]>

commit e41a49fadbc80b60b48d3c095d9e2ee7ef7c9a8e upstream.

It turns out that SLUB redzoning ("slub_debug=Z") checks from s->object_size rather than from s->inuse (which is normally bumped to make room for the freelist pointer), so a cache created with an object size less than 24 would have the freelist pointer written beyond s->object_size, causing the redzone to be corrupted by the freelist pointer. This was very visible with "slub_debug=ZF":

BUG test (Tainted: G B ): Right Redzone overwritten
-----------------------------------------------------------------------------

INFO: 0xffff957ead1c05de-0xffff957ead1c05df @offset=1502. First byte 0x1a instead of 0xbb
INFO: Slab 0xffffef3950b47000 objects=170 used=170 fp=0x0000000000000000 flags=0x8000000000000200
INFO: Object 0xffff957ead1c05d8 @offset=1496 fp=0xffff957ead1c0620

  Redzone  (____ptrval____): bb bb bb bb bb bb bb bb               ........
  Object   (____ptrval____): 00 00 00 00 00 f6 f4 a5               ........
  Redzone  (____ptrval____): 40 1d e8 1a aa                        @....
  Padding  (____ptrval____): 00 00 00 00 00 00 00 00               ........

Adjust the offset to stay within s->object_size.

(Note that no caches of in this size range are known to exist in the kernel currently.)

---
 mm/slub.c |   14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

@@ -3687,7 +3687,6 @@ static int calculate_sizes(struct kmem_c
 {
 	slab_flags_t flags = s->flags;
 	unsigned int size = s->object_size;
-	unsigned int freepointer_area;
 	unsigned int order;
 
 	/*

@@ -3696,13 +3695,6 @@ static int calculate_sizes(struct kmem_c
 	 * the possible location of the free pointer.
 	 */
 	size = ALIGN(size, sizeof(void *));
-	/*
-	 * This is the area of the object where a freepointer can be
-	 * safely written. If redzoning adds more to the inuse size, we
-	 * can't use that portion for writing the freepointer, so
-	 * s->offset must be limited within this for the general case.
-	 */
-	freepointer_area = size;
 
 #ifdef CONFIG_SLUB_DEBUG
 	/*

@@ -3728,7 +3720,7 @@ static int calculate_sizes(struct kmem_c
 
 	/*
 	 * With that we have determined the number of bytes in actual use
-	 * by the object. This is the potential offset to the free pointer.
+	 * by the object and redzoning.
 	 */
 	s->inuse = size;
 

@@ -3751,13 +3743,13 @@ static int calculate_sizes(struct kmem_c
 		 */
 		s->offset = size;
 		size += sizeof(void *);
-	} else if (freepointer_area > sizeof(void *)) {
+	} else {
 		/*
 		 * Store freelist pointer near middle of object to keep
 		 * it away from the edges of the object to avoid small
 		 * sized over/underflows from neighboring allocations.
 		 */
-		s->offset = ALIGN(freepointer_area / 2, sizeof(void *));
+		s->offset = ALIGN_DOWN(s->object_size / 2, sizeof(void *));
 	}
 
 #ifdef CONFIG_SLUB_DEBUG

From: Andrew Morton <[email protected]>

commit 1b3865d016815cbd69a1879ca1c8a8901fda1072 upstream.

Fixes build with CONFIG_SLAB_FREELIST_HARDENED=y.

Hopefully. But it's the right thing to do anwyay.

---
 mm/slub.c |    1 +
 1 file changed, 1 insertion(+)

@@ -15,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/bit_spinlock.h>
 #include <linux/interrupt.h>
+#include <linux/swab.h>
 #include <linux/bitops.h>
 #include <linux/slab.h>
 #include "slab.h"

From: Joakim Zhang <[email protected]>

commit 8f269102baf788aecfcbbc6313b6bceb54c9b990 upstream.

Platform drivers may call stmmac_probe_config_dt() to parse dt, could call stmmac_remove_config_dt() in error handing after dt parsed, so need disable clocks in stmmac_remove_config_dt().

Go through all platforms drivers which use stmmac_probe_config_dt(), none of them disable clocks manually, so it's safe to disable them in stmmac_remove_config_dt().

---
 drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -622,6 +622,8 @@ error_pclk_get:
 void stmmac_remove_config_dt(struct platform_device *pdev,
 			     struct plat_stmmacenet_data *plat)
 {
+	clk_disable_unprepare(plat->stmmac_clk);
+	clk_disable_unprepare(plat->pclk);
 	of_node_put(plat->phy_node);
 	of_node_put(plat->mdio_node);
 }

From: Fugang Duan <[email protected]>

commit cb3cefe3f3f8af27c6076ef7d1f00350f502055d upstream.

Add clock rate zero check to fix coverity issue of "divide by 0".

---
 drivers/net/ethernet/freescale/fec_ptp.c |    4 ++++
 1 file changed, 4 insertions(+)

@@ -602,6 +602,10 @@ void fec_ptp_init(struct platform_device
 	fep->ptp_caps.enable = fec_ptp_enable;
 
 	fep->cycle_speed = clk_get_rate(fep->clk_ptp);
+	if (!fep->cycle_speed) {
+		fep->cycle_speed = NSEC_PER_SEC;
+		dev_err(&fep->pdev->dev, "clk_ptp clock rate is zero\n");
+	}
 	fep->ptp_inc = NSEC_PER_SEC / fep->cycle_speed;
 
 	spin_lock_init(&fep->tmreg_lock);

From: Arnaldo Carvalho de Melo <[email protected]>

commit 1792a59eab9593de2eae36c40c5a22d70f52c026 upstream.

To pick the changes in:

321827477360934d ("icmp: don't send out ICMP messages with a source address of 0.0.0.0")

That don't result in any change in tooling, as INADDR_ are not used to generate id->string tables used by 'perf trace'.

This addresses this build warning:

Warning: Kernel ABI header at 'tools/include/uapi/linux/in.h' differs from latest version at 'include/uapi/linux/in.h' diff -u tools/include/uapi/linux/in.h include/uapi/linux/in.h

---
 tools/include/uapi/linux/in.h |    3 +++
 1 file changed, 3 insertions(+)

@@ -289,6 +289,9 @@ struct sockaddr_in {
 /* Address indicating an error return. */
 #define	INADDR_NONE		((unsigned long int) 0xffffffff)
 
+/* Dummy address for src of ICMP replies if no real address is set (RFC7600). */
+#define	INADDR_DUMMY		((unsigned long int) 0xc0000008)
+
 /* Network number for local host loopback. */
 #define	IN_LOOPBACKNET		127
 

From: Arnaldo Carvalho de Melo <[email protected]>

commit ef83f9efe8461b8fd71eb60b53dbb6a5dd7b39e9 upstream.

To pick the changes in:

ea6932d70e223e02 ("net: make get_net_ns return error if NET_NS is disabled")

That don't result in any changes in the tables generated from that header.

This silences this perf build warning:

Warning: Kernel ABI header at 'tools/perf/trace/beauty/include/linux/socket.h' differs from latest version at 'include/linux/socket.h' diff -u tools/perf/trace/beauty/include/linux/socket.h include/linux/socket.h

---
 tools/perf/trace/beauty/include/linux/socket.h |    2 --
 1 file changed, 2 deletions(-)

@@ -438,6 +438,4 @@ extern int __sys_socketpair(int family,
 			    int __user *usockvec);
 extern int __sys_shutdown_sock(struct socket *sock, int how);
 extern int __sys_shutdown(int fd, int how);
-
-extern struct ns_common *get_net_ns(struct ns_common *ns);
 #endif /* _LINUX_SOCKET_H */

From: Jack Pham <[email protected]>

commit 8d396bb0a5b62b326f6be7594d8bd46b088296bd upstream.

The DWC3 DebugFS directory and files are currently created once during probe. This includes creation of subdirectories for each of the gadget's endpoints. This works fine for peripheral-only controllers, as dwc3_core_init_mode() calls dwc3_gadget_init() just prior to calling dwc3_debugfs_init().

However, for dual-role controllers, dwc3_core_init_mode() will instead call dwc3_drd_init() which is problematic in a few ways. First, the initial state must be determined, then dwc3_set_mode() will have to schedule drd_work and by then dwc3_debugfs_init() could have already been invoked. Even if the initial mode is peripheral, dwc3_gadget_init() happens after the DebugFS files are created, and worse so if the initial state is host and the controller switches to peripheral much later. And secondly, even if the gadget endpoints' debug entries were successfully created, if the controller exits peripheral mode, its dwc3_eps are freed so the debug files would now hold stale references.

So it is best if the DebugFS endpoint entries are created and removed dynamically at the same time the underlying dwc3_eps are. Do this by calling dwc3_debugfs_create_endpoint_dir() as each endpoint is created, and conversely remove the DebugFS entry when the endpoint is freed.

---
 drivers/usb/dwc3/debug.h   |    3 +++
 drivers/usb/dwc3/debugfs.c |   21 ++-------------------
 drivers/usb/dwc3/gadget.c  |    3 +++
 3 files changed, 8 insertions(+), 19 deletions(-)

@@ -413,9 +413,12 @@ static inline const char *dwc3_gadget_ge
 
 
 #ifdef CONFIG_DEBUG_FS
+extern void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep);
 extern void dwc3_debugfs_init(struct dwc3 *d);
 extern void dwc3_debugfs_exit(struct dwc3 *d);
 #else
+static inline void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep)
+{  }
 static inline void dwc3_debugfs_init(struct dwc3 *d)
 {  }
 static inline void dwc3_debugfs_exit(struct dwc3 *d)

@@ -890,30 +890,14 @@ static void dwc3_debugfs_create_endpoint
 	}
 }
 
-static void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep,
-		struct dentry *parent)
+void dwc3_debugfs_create_endpoint_dir(struct dwc3_ep *dep)
 {
 	struct dentry		*dir;
 
-	dir = debugfs_create_dir(dep->name, parent);
+	dir = debugfs_create_dir(dep->name, dep->dwc->root);
 	dwc3_debugfs_create_endpoint_files(dep, dir);
 }
 
-static void dwc3_debugfs_create_endpoint_dirs(struct dwc3 *dwc,
-		struct dentry *parent)
-{
-	int			i;
-
-	for (i = 0; i < dwc->num_eps; i++) {
-		struct dwc3_ep	*dep = dwc->eps[i];
-
-		if (!dep)
-			continue;
-
-		dwc3_debugfs_create_endpoint_dir(dep, parent);
-	}
-}
-
 void dwc3_debugfs_init(struct dwc3 *dwc)
 {
 	struct dentry		*root;

@@ -944,7 +928,6 @@ void dwc3_debugfs_init(struct dwc3 *dwc)
 				&dwc3_testmode_fops);
 		debugfs_create_file("link_state", 0644, root, dwc,
 				    &dwc3_link_state_fops);
-		dwc3_debugfs_create_endpoint_dirs(dwc, root);
 	}
 }
 

@@ -2719,6 +2719,8 @@ static int dwc3_gadget_init_endpoint(str
 	INIT_LIST_HEAD(&dep->started_list);
 	INIT_LIST_HEAD(&dep->cancelled_list);
 
+	dwc3_debugfs_create_endpoint_dir(dep);
+
 	return 0;
 }
 

@@ -2762,6 +2764,7 @@ static void dwc3_gadget_free_endpoints(s
 			list_del(&dep->endpoint.ep_list);
 		}
 
+		debugfs_remove_recursive(debugfs_lookup(dep->name, dwc->root));
 		kfree(dep);
 	}
 }

From: Peter Chen <[email protected]>

commit 4bf584a03eec674975ee9fe36c8583d9d470dab1 upstream.

When do system reboot, it calls dwc3_shutdown and the whole debugfs for dwc3 has removed first, when the gadget tries to do deinit, and remove debugfs for its endpoints, it meets NULL pointer dereference issue when call debugfs_lookup. Fix it by removing the whole dwc3 debugfs later than dwc3_drd_exit.

[ 2924.958838] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000002
....
[ 2925.030994] pstate: 60000005 (nZCv daif -PAN -UAO -TCO BTYPE=--)
[ 2925.037005] pc : inode_permission+0x2c/0x198
[ 2925.041281] lr : lookup_one_len_common+0xb0/0xf8
[ 2925.045903] sp : ffff80001276ba70
[ 2925.049218] x29: ffff80001276ba70 x28: ffff0000c01f0000 x27: 0000000000000000
[ 2925.056364] x26: ffff800011791e70 x25: 0000000000000008 x24: dead000000000100
[ 2925.063510] x23: dead000000000122 x22: 0000000000000000 x21: 0000000000000001
[ 2925.070652] x20: ffff8000122c6188 x19: 0000000000000000 x18: 0000000000000000
[ 2925.077797] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000004
[ 2925.084943] x14: ffffffffffffffff x13: 0000000000000000 x12: 0000000000000030
[ 2925.092087] x11: 0101010101010101 x10: 7f7f7f7f7f7f7f7f x9 : ffff8000102b2420
[ 2925.099232] x8 : 7f7f7f7f7f7f7f7f x7 : feff73746e2f6f64 x6 : 0000000000008080
[ 2925.106378] x5 : 61c8864680b583eb x4 : 209e6ec2d263dbb7 x3 : 000074756f307065
[ 2925.113523] x2 : 0000000000000001 x1 : 0000000000000000 x0 : ffff8000122c6188
[ 2925.120671] Call trace:
[ 2925.123119]  inode_permission+0x2c/0x198
[ 2925.127042]  lookup_one_len_common+0xb0/0xf8
[ 2925.131315]  lookup_one_len_unlocked+0x34/0xb0
[ 2925.135764]  lookup_positive_unlocked+0x14/0x50
[ 2925.140296]  debugfs_lookup+0x68/0xa0
[ 2925.143964]  dwc3_gadget_free_endpoints+0x84/0xb0
[ 2925.148675]  dwc3_gadget_exit+0x28/0x78
[ 2925.152518]  dwc3_drd_exit+0x100/0x1f8
[ 2925.156267]  dwc3_remove+0x11c/0x120
[ 2925.159851]  dwc3_shutdown+0x14/0x20
[ 2925.163432]  platform_shutdown+0x28/0x38
[ 2925.167360]  device_shutdown+0x15c/0x378
[ 2925.171291]  kernel_restart_prepare+0x3c/0x48
[ 2925.175650]  kernel_restart+0x1c/0x68
[ 2925.179316]  __do_sys_reboot+0x218/0x240
[ 2925.183247]  __arm64_sys_reboot+0x28/0x30
[ 2925.187262]  invoke_syscall+0x48/0x100
[ 2925.191017]  el0_svc_common.constprop.0+0x48/0xc8
[ 2925.195726]  do_el0_svc+0x28/0x88
[ 2925.199045]  el0_svc+0x20/0x30
[ 2925.202104]  el0_sync_handler+0xa8/0xb0
[ 2925.205942]  el0_sync+0x148/0x180
[ 2925.209270] Code: a9025bf5 2a0203f5 121f0056 370802b5 (79400660)
[ 2925.215372] ---[ end trace 124254d8e485a58b ]---
[ 2925.220012] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
[ 2925.227676] Kernel Offset: disabled
[ 2925.231164] CPU features: 0x00001001,20000846
[ 2925.235521] Memory Limit: none
[ 2925.238580] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---

---
 drivers/usb/dwc3/core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -1657,8 +1657,8 @@ static int dwc3_remove(struct platform_d
 
 	pm_runtime_get_sync(&pdev->dev);
 
-	dwc3_debugfs_exit(dwc);
 	dwc3_core_exit_mode(dwc);
+	dwc3_debugfs_exit(dwc);
 
 	dwc3_core_exit(dwc);
 	dwc3_ulpi_exit(dwc);

On ARCH_BRCMSTB, using 32-bit and 64-bit ARM kernels:

Florian

Results from Linaro’s test farm.
No regressions on arm64, arm, x86_64, and i386.

## Build
* kernel: 5.12.13-rc1
* git: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
* git branch: linux-5.12.y
* git commit: 88a915cf22fcd20d2323dff7a4b0f70909cf4099
* git describe: v5.12.12-179-g88a915cf22fc
* test details:
https://qa-reports.linaro.org/lkft/linux-stable-rc-linux-5.12.y/build/v5.12.12-179-g88a915cf22fc

## No regressions (compared to v5.12.11-49-g3197a891c08a)

## No fixes (compared to v5.12.11-49-g3197a891c08a)

## Test result summary
total: 92709, pass: 74966, fail: 3757, skip: 13183, xfail: 803,

## Build Summary
* arc: 10 total, 10 passed, 0 failed
* arm: 193 total, 193 passed, 0 failed
* arm64: 27 total, 27 passed, 0 failed
* dragonboard-410c: 2 total, 2 passed, 0 failed
* hi6220-hikey: 2 total, 2 passed, 0 failed
* i386: 27 total, 27 passed, 0 failed
* juno-r2: 2 total, 2 passed, 0 failed
* mips: 45 total, 45 passed, 0 failed
* parisc: 9 total, 9 passed, 0 failed
* powerpc: 27 total, 27 passed, 0 failed
* riscv: 21 total, 21 passed, 0 failed
* s390: 18 total, 18 passed, 0 failed
* sh: 18 total, 18 passed, 0 failed
* sparc: 9 total, 9 passed, 0 failed
* x15: 2 total, 0 passed, 2 failed
* x86: 2 total, 2 passed, 0 failed
* x86_64: 27 total, 27 passed, 0 failed

## Test suites summary
* fwts
* igt-gpu-tools
* install-android-platform-tools-r2600
* kselftest-
* kselftest-android
* kselftest-bpf
* kselftest-breakpoints
* kselftest-capabilities
* kselftest-cgroup
* kselftest-clone3
* kselftest-core
* kselftest-cpu-hotplug
* kselftest-cpufreq
* kselftest-drivers
* kselftest-efivarfs
* kselftest-filesystems
* kselftest-firmware
* kselftest-fpu
* kselftest-futex
* kselftest-gpio
* kselftest-intel_pstate
* kselftest-ipc
* kselftest-ir
* kselftest-kcmp
* kselftest-kexec
* kselftest-kvm
* kselftest-lib
* kselftest-livepatch
* kselftest-lkdtm
* kselftest-membarrier
* kselftest-memfd
* kselftest-memory-hotplug
* kselftest-mincore
* kselftest-mount
* kselftest-mqueue
* kselftest-net
* kselftest-netfilter
* kselftest-nsfs
* kselftest-openat2
* kselftest-pid_namespace
* kselftest-pidfd
* kselftest-proc
* kselftest-pstore
* kselftest-ptrace
* kselftest-rseq
* kselftest-rtc
* kselftest-seccomp
* kselftest-sigaltstack
* kselftest-size
* kselftest-splice
* kselftest-static_keys
* kselftest-sync
* kselftest-sysctl
* kselftest-tc-testing
* kselftest-timens
* kselftest-timers
* kselftest-tmpfs
* kselftest-tpm2
* kselftest-user
* kselftest-vm
* kselftest-vsyscall-mode-native-
* kselftest-vsyscall-mode-none-
* kselftest-x86
* kselftest-zram
* kunit
* kvm-unit-tests
* libhugetlbfs
* linux-log-parser
* ltp-cap_bounds-tests
* ltp-commands-tests
* ltp-containers-tests
* ltp-controllers-tests
* ltp-cpuhotplug-tests
* ltp-crypto-tests
* ltp-cve-tests
* ltp-dio-tests
* ltp-fcntl-locktests-tests
* ltp-filecaps-tests
* ltp-fs-tests
* ltp-fs_bind-tests
* ltp-fs_perms_simple-tests
* ltp-fsx-tests
* ltp-hugetlb-tests
* ltp-io-tests
* ltp-ipc-tests
* ltp-math-tests
* ltp-mm-tests
* ltp-nptl-tests
* ltp-open-posix-tests
* ltp-pty-tests
* ltp-sched-tests
* ltp-securebits-tests
* ltp-syscalls-tests
* ltp-tracing-tests
* network-basic-tests
* packetdrill
* perf
* rcutorture
* ssuite
* v4l2-compliance

--
Linaro LKFT
https://lkft.linaro.org

All tests passing for Tegra ...

Test results for stable-v5.12:

    12 builds:	12 pass, 0 fail
    28 boots:	28 pass, 0 fail
    104 tests:	104 pass, 0 fail

Linux version: 5.12.13-rc1-g88a915cf22fc
Boards tested: tegra124-jetson-tk1, tegra186-p2771-0000,

                tegra194-p2972-0000, tegra194-p3509-0000+p3668-0000,
                tegra20-ventana, tegra210-p2371-2180,
                tegra210-p3450-0000, tegra30-cardhu-a04

Jon

Build results:

	total: 151 pass: 151 fail: 0
Qemu test results:
	total: 462 pass: 462 fail: 0

Guenter

Compiled and booted on my test system. No dmesg regressions.

thanks,
-- Shuah

Tested ok on:
- Intel NUC11 x86_64 (Tiger Lake - TGL)
- Radxa ROCK Pi N10 arm64 (rk3399pro)

--
Rudi

5.12.13-rc1 Successfully Compiled and booted on my Raspberry PI 4b (8g) (bcm2711)