[PATCH AUTOSEL 4.9 01/21] mm/vmstat.c: assert that vmstat_text is in sync with stat_items_size

[PATCH AUTOSEL 4.9 01/21] mm/vmstat.c: assert that vmstat_text is in sync with stat_items_size

[Sasha Levin]

From: Jann Horn <jannh@google.com>

[ Upstream commit f0ecf25a093fc0589f0a6bc4c1ea068bbb67d220 ]

Having two gigantic arrays that must manually be kept in sync, including
ifdefs, isn't exactly robust.  To make it easier to catch such issues in
the future, add a BUILD_BUG_ON().

Link: http://lkml.kernel.org/r/20181001143138.95119-3-jannh@google.com
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Kemi Wang <kemi.wang@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 mm/vmstat.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 5e6a4d76659d..2bab38d5570c 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1484,6 +1484,8 @@ static void *vmstat_start(struct seq_file *m, loff_t *pos)
 	stat_items_size += sizeof(struct vm_event_state);
 #endif
 
+	BUILD_BUG_ON(stat_items_size !=
+		     ARRAY_SIZE(vmstat_text) * sizeof(unsigned long));
 	v = kmalloc(stat_items_size, GFP_KERNEL);
 	m->private = v;
 	if (!v)
-- 
2.17.1

[PATCH AUTOSEL 4.9 02/21] userfaultfd: allow get_mempolicy(MPOL_F_NODE|MPOL_F_ADDR) to trigger userfaults

[Sasha Levin]

From: Andrea Arcangeli <aarcange@redhat.com>

[ Upstream commit 3b9aadf7278d16d7bed4d5d808501065f70898d8 ]

get_mempolicy(MPOL_F_NODE|MPOL_F_ADDR) called a get_user_pages that would
not be waiting for userfaults before failing and it would hit on a SIGBUS
instead.  Using get_user_pages_locked/unlocked instead will allow
get_mempolicy to allow userfaults to resolve the fault and fill the hole,
before grabbing the node id of the page.

If the user calls get_mempolicy() with MPOL_F_ADDR | MPOL_F_NODE for an
address inside an area managed by uffd and there is no page at that
address, the page allocation from within get_mempolicy() will fail
because get_user_pages() does not allow for page fault retry required
for uffd; the user will get SIGBUS.

With this patch, the page fault will be resolved by the uffd and the
get_mempolicy() will continue normally.

Background:

Via code review, previously the syscall would have returned -EFAULT
(vm_fault_to_errno), now it will block and wait for an userfault (if
it's waken before the fault is resolved it'll still -EFAULT).

This way get_mempolicy will give a chance to an "unaware" app to be
compliant with userfaults.

The reason this visible change is that becoming "userfault compliant"
cannot regress anything: all other syscalls including read(2)/write(2)
had to become "userfault compliant" long time ago (that's one of the
things userfaultfd can do that PROT_NONE and trapping segfaults can't).

So this is just one more syscall that become "userfault compliant" like
all other major ones already were.

This has been happening on virtio-bridge dpdk process which just called
get_mempolicy on the guest space post live migration, but before the
memory had a chance to be migrated to destination.

I didn't run an strace to be able to show the -EFAULT going away, but
I've the confirmation of the below debug aid information (only visible
with CONFIG_DEBUG_VM=y) going away with the patch:

    [20116.371461] FAULT_FLAG_ALLOW_RETRY missing 0
    [20116.371464] CPU: 1 PID: 13381 Comm: vhost-events Not tainted 4.17.12-200.fc28.x86_64 #1
    [20116.371465] Hardware name: LENOVO 20FAS2BN0A/20FAS2BN0A, BIOS N1CET54W (1.22 ) 02/10/2017
    [20116.371466] Call Trace:
    [20116.371473]  dump_stack+0x5c/0x80
    [20116.371476]  handle_userfault.cold.37+0x1b/0x22
    [20116.371479]  ? remove_wait_queue+0x20/0x60
    [20116.371481]  ? poll_freewait+0x45/0xa0
    [20116.371483]  ? do_sys_poll+0x31c/0x520
    [20116.371485]  ? radix_tree_lookup_slot+0x1e/0x50
    [20116.371488]  shmem_getpage_gfp+0xce7/0xe50
    [20116.371491]  ? page_add_file_rmap+0x1a/0x2c0
    [20116.371493]  shmem_fault+0x78/0x1e0
    [20116.371495]  ? filemap_map_pages+0x3a1/0x450
    [20116.371498]  __do_fault+0x1f/0xc0
    [20116.371500]  __handle_mm_fault+0xe2e/0x12f0
    [20116.371502]  handle_mm_fault+0xda/0x200
    [20116.371504]  __get_user_pages+0x238/0x790
    [20116.371506]  get_user_pages+0x3e/0x50
    [20116.371510]  kernel_get_mempolicy+0x40b/0x700
    [20116.371512]  ? vfs_write+0x170/0x1a0
    [20116.371515]  __x64_sys_get_mempolicy+0x21/0x30
    [20116.371517]  do_syscall_64+0x5b/0x160
    [20116.371520]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

The above harmless debug message (not a kernel crash, just a
dump_stack()) is shown with CONFIG_DEBUG_VM=y to more quickly identify
and improve kernel spots that may have to become "userfaultfd
compliant" like this one (without having to run an strace and search
for syscall misbehavior).  Spots like the above are more closer to a
kernel bug for the non-cooperative usages that Mike focuses on, than
for for dpdk qemu-cooperative usages that reproduced it, but it's still
nicer to get this fixed for dpdk too.

The part of the patch that caused me to think is only the
implementation issue of mpol_get, but it looks like it should work safe
no matter the kind of mempolicy structure that is (the default static
policy also starts at 1 so it'll go to 2 and back to 1 without crashing
everything at 0).

[rppt@linux.vnet.ibm.com: changelog addition]
  http://lkml.kernel.org/r/20180904073718.GA26916@rapoport-lnx
Link: http://lkml.kernel.org/r/20180831214848.23676-1-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Tested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 mm/mempolicy.c | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 69c4a0c92ebb..625122adefe0 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -845,16 +845,19 @@ static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes)
 	}
 }
 
-static int lookup_node(unsigned long addr)
+static int lookup_node(struct mm_struct *mm, unsigned long addr)
 {
 	struct page *p;
 	int err;
 
-	err = get_user_pages(addr & PAGE_MASK, 1, 0, &p, NULL);
+	int locked = 1;
+	err = get_user_pages_locked(addr & PAGE_MASK, 1, 0, &p, &locked);
 	if (err >= 0) {
 		err = page_to_nid(p);
 		put_page(p);
 	}
+	if (locked)
+		up_read(&mm->mmap_sem);
 	return err;
 }
 
@@ -865,7 +868,7 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
 	int err;
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma = NULL;
-	struct mempolicy *pol = current->mempolicy;
+	struct mempolicy *pol = current->mempolicy, *pol_refcount = NULL;
 
 	if (flags &
 		~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED))
@@ -905,7 +908,16 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
 
 	if (flags & MPOL_F_NODE) {
 		if (flags & MPOL_F_ADDR) {
-			err = lookup_node(addr);
+			/*
+			 * Take a refcount on the mpol, lookup_node()
+			 * wil drop the mmap_sem, so after calling
+			 * lookup_node() only "pol" remains valid, "vma"
+			 * is stale.
+			 */
+			pol_refcount = pol;
+			vma = NULL;
+			mpol_get(pol);
+			err = lookup_node(mm, addr);
 			if (err < 0)
 				goto out;
 			*policy = err;
@@ -940,7 +952,9 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
  out:
 	mpol_cond_put(pol);
 	if (vma)
-		up_read(&current->mm->mmap_sem);
+		up_read(&mm->mmap_sem);
+	if (pol_refcount)
+		mpol_put(pol_refcount);
 	return err;
 }
 
-- 
2.17.1

[PATCH AUTOSEL 4.9 03/21] mm: don't warn about large allocations for slab

[Sasha Levin]

From: Dmitry Vyukov <dvyukov@google.com>

[ Upstream commit 61448479a9f2c954cde0cfe778cb6bec5d0a748d ]

Slub does not call kmalloc_slab() for sizes > KMALLOC_MAX_CACHE_SIZE,
instead it falls back to kmalloc_large().

For slab KMALLOC_MAX_CACHE_SIZE == KMALLOC_MAX_SIZE and it calls
kmalloc_slab() for all allocations relying on NULL return value for
over-sized allocations.

This inconsistency leads to unwanted warnings from kmalloc_slab() for
over-sized allocations for slab.  Returning NULL for failed allocations is
the expected behavior.

Make slub and slab code consistent by checking size >
KMALLOC_MAX_CACHE_SIZE in slab before calling kmalloc_slab().

While we are here also fix the check in kmalloc_slab().  We should check
against KMALLOC_MAX_CACHE_SIZE rather than KMALLOC_MAX_SIZE.  It all kinda
worked because for slab the constants are the same, and slub always checks
the size against KMALLOC_MAX_CACHE_SIZE before kmalloc_slab().  But if we
get there with size > KMALLOC_MAX_CACHE_SIZE anyhow bad things will
happen.  For example, in case of a newly introduced bug in slub code.

Also move the check in kmalloc_slab() from function entry to the size >
192 case.  This partially compensates for the additional check in slab
code and makes slub code a bit faster (at least theoretically).

Also drop __GFP_NOWARN in the warning check.  This warning means a bug in
slab code itself, user-passed flags have nothing to do with it.

Nothing of this affects slob.

Link: http://lkml.kernel.org/r/20180927171502.226522-1-dvyukov@gmail.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: syzbot+87829a10073277282ad1@syzkaller.appspotmail.com
Reported-by: syzbot+ef4e8fc3a06e9019bb40@syzkaller.appspotmail.com
Reported-by: syzbot+6e438f4036df52cbb863@syzkaller.appspotmail.com
Reported-by: syzbot+8574471d8734457d98aa@syzkaller.appspotmail.com
Reported-by: syzbot+af1504df0807a083dbd9@syzkaller.appspotmail.com
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 mm/slab.c        |  4 ++++
 mm/slab_common.c | 12 ++++++------
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/mm/slab.c b/mm/slab.c
index c59844dbd034..263dcda6897b 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3690,6 +3690,8 @@ __do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller)
 	struct kmem_cache *cachep;
 	void *ret;
 
+	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE))
+		return NULL;
 	cachep = kmalloc_slab(size, flags);
 	if (unlikely(ZERO_OR_NULL_PTR(cachep)))
 		return cachep;
@@ -3725,6 +3727,8 @@ static __always_inline void *__do_kmalloc(size_t size, gfp_t flags,
 	struct kmem_cache *cachep;
 	void *ret;
 
+	if (unlikely(size > KMALLOC_MAX_CACHE_SIZE))
+		return NULL;
 	cachep = kmalloc_slab(size, flags);
 	if (unlikely(ZERO_OR_NULL_PTR(cachep)))
 		return cachep;
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 622f6b6ae844..13f1926f8fcd 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -883,18 +883,18 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags)
 {
 	int index;
 
-	if (unlikely(size > KMALLOC_MAX_SIZE)) {
-		WARN_ON_ONCE(!(flags & __GFP_NOWARN));
-		return NULL;
-	}
-
 	if (size <= 192) {
 		if (!size)
 			return ZERO_SIZE_PTR;
 
 		index = size_index[size_index_elem(size)];
-	} else
+	} else {
+		if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) {
+			WARN_ON(1);
+			return NULL;
+		}
 		index = fls(size - 1);
+	}
 
 #ifdef CONFIG_ZONE_DMA
 	if (unlikely((flags & GFP_DMA)))
-- 
2.17.1

[PATCH AUTOSEL 4.9 04/21] powerpc/eeh: Fix possible null deref in eeh_dump_dev_log()

[Sasha Levin]

From: Sam Bobroff <sbobroff@linux.ibm.com>

[ Upstream commit f9bc28aedfb5bbd572d2d365f3095c1becd7209b ]

If an error occurs during an unplug operation, it's possible for
eeh_dump_dev_log() to be called when edev->pdn is null, which
currently leads to dereferencing a null pointer.

Handle this by skipping the error log for those devices.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/kernel/eeh.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
index e5bfbf62827a..8336b9016ca9 100644
--- a/arch/powerpc/kernel/eeh.c
+++ b/arch/powerpc/kernel/eeh.c
@@ -169,6 +169,11 @@ static size_t eeh_dump_dev_log(struct eeh_dev *edev, char *buf, size_t len)
 	int n = 0, l = 0;
 	char buffer[128];
 
+	if (!pdn) {
+		pr_warn("EEH: Note: No error log for absent device.\n");
+		return 0;
+	}
+
 	n += scnprintf(buf+n, len-n, "%04x:%02x:%02x.%01x\n",
 		       edev->phb->global_number, pdn->busno,
 		       PCI_SLOT(pdn->devfn), PCI_FUNC(pdn->devfn));
-- 
2.17.1

[PATCH AUTOSEL 4.9 05/21] tty: check name length in tty_find_polling_driver()

[Sasha Levin]

From: Miles Chen <miles.chen@mediatek.com>

[ Upstream commit 33a1a7be198657c8ca26ad406c4d2a89b7162bcc ]

The issue is found by a fuzzing test.
If tty_find_polling_driver() recevies an incorrect input such as
',,' or '0b', the len becomes 0 and strncmp() always return 0.
In this case, a null p->ops->poll_init() is called and it causes a kernel
panic.

Fix this by checking name length against zero in tty_find_polling_driver().

$echo ,, > /sys/module/kgdboc/parameters/kgdboc
[   20.804451] WARNING: CPU: 1 PID: 104 at drivers/tty/serial/serial_core.c:457
uart_get_baud_rate+0xe8/0x190
[   20.804917] Modules linked in:
[   20.805317] CPU: 1 PID: 104 Comm: sh Not tainted 4.19.0-rc7ajb #8
[   20.805469] Hardware name: linux,dummy-virt (DT)
[   20.805732] pstate: 20000005 (nzCv daif -PAN -UAO)
[   20.805895] pc : uart_get_baud_rate+0xe8/0x190
[   20.806042] lr : uart_get_baud_rate+0xc0/0x190
[   20.806476] sp : ffffffc06acff940
[   20.806676] x29: ffffffc06acff940 x28: 0000000000002580
[   20.806977] x27: 0000000000009600 x26: 0000000000009600
[   20.807231] x25: ffffffc06acffad0 x24: 00000000ffffeff0
[   20.807576] x23: 0000000000000001 x22: 0000000000000000
[   20.807807] x21: 0000000000000001 x20: 0000000000000000
[   20.808049] x19: ffffffc06acffac8 x18: 0000000000000000
[   20.808277] x17: 0000000000000000 x16: 0000000000000000
[   20.808520] x15: ffffffffffffffff x14: ffffffff00000000
[   20.808757] x13: ffffffffffffffff x12: 0000000000000001
[   20.809011] x11: 0101010101010101 x10: ffffff880d59ff5f
[   20.809292] x9 : ffffff880d59ff5e x8 : ffffffc06acffaf3
[   20.809549] x7 : 0000000000000000 x6 : ffffff880d59ff5f
[   20.809803] x5 : 0000000080008001 x4 : 0000000000000003
[   20.810056] x3 : ffffff900853e6b4 x2 : dfffff9000000000
[   20.810693] x1 : ffffffc06acffad0 x0 : 0000000000000cb0
[   20.811005] Call trace:
[   20.811214]  uart_get_baud_rate+0xe8/0x190
[   20.811479]  serial8250_do_set_termios+0xe0/0x6f4
[   20.811719]  serial8250_set_termios+0x48/0x54
[   20.811928]  uart_set_options+0x138/0x1bc
[   20.812129]  uart_poll_init+0x114/0x16c
[   20.812330]  tty_find_polling_driver+0x158/0x200
[   20.812545]  configure_kgdboc+0xbc/0x1bc
[   20.812745]  param_set_kgdboc_var+0xb8/0x150
[   20.812960]  param_attr_store+0xbc/0x150
[   20.813160]  module_attr_store+0x40/0x58
[   20.813364]  sysfs_kf_write+0x8c/0xa8
[   20.813563]  kernfs_fop_write+0x154/0x290
[   20.813764]  vfs_write+0xf0/0x278
[   20.813951]  __arm64_sys_write+0x84/0xf4
[   20.814400]  el0_svc_common+0xf4/0x1dc
[   20.814616]  el0_svc_handler+0x98/0xbc
[   20.814804]  el0_svc+0x8/0xc
[   20.822005] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[   20.826913] Mem abort info:
[   20.827103]   ESR = 0x84000006
[   20.827352]   Exception class = IABT (current EL), IL = 16 bits
[   20.827655]   SET = 0, FnV = 0
[   20.827855]   EA = 0, S1PTW = 0
[   20.828135] user pgtable: 4k pages, 39-bit VAs, pgdp = (____ptrval____)
[   20.828484] [0000000000000000] pgd=00000000aadee003, pud=00000000aadee003, pmd=0000000000000000
[   20.829195] Internal error: Oops: 84000006 [#1] SMP
[   20.829564] Modules linked in:
[   20.829890] CPU: 1 PID: 104 Comm: sh Tainted: G        W         4.19.0-rc7ajb #8
[   20.830545] Hardware name: linux,dummy-virt (DT)
[   20.830829] pstate: 60000085 (nZCv daIf -PAN -UAO)
[   20.831174] pc :           (null)
[   20.831457] lr : serial8250_do_set_termios+0x358/0x6f4
[   20.831727] sp : ffffffc06acff9b0
[   20.831936] x29: ffffffc06acff9b0 x28: ffffff9008d7c000
[   20.832267] x27: ffffff900969e16f x26: 0000000000000000
[   20.832589] x25: ffffff900969dfb0 x24: 0000000000000000
[   20.832906] x23: ffffffc06acffad0 x22: ffffff900969e160
[   20.833232] x21: 0000000000000000 x20: ffffffc06acffac8
[   20.833559] x19: ffffff900969df90 x18: 0000000000000000
[   20.833878] x17: 0000000000000000 x16: 0000000000000000
[   20.834491] x15: ffffffffffffffff x14: ffffffff00000000
[   20.834821] x13: ffffffffffffffff x12: 0000000000000001
[   20.835143] x11: 0101010101010101 x10: ffffff880d59ff5f
[   20.835467] x9 : ffffff880d59ff5e x8 : ffffffc06acffaf3
[   20.835790] x7 : 0000000000000000 x6 : ffffff880d59ff5f
[   20.836111] x5 : c06419717c314100 x4 : 0000000000000007
[   20.836419] x3 : 0000000000000000 x2 : 0000000000000000
[   20.836732] x1 : 0000000000000001 x0 : ffffff900969df90
[   20.837100] Process sh (pid: 104, stack limit = 0x(____ptrval____))
[   20.837396] Call trace:
[   20.837566]            (null)
[   20.837816]  serial8250_set_termios+0x48/0x54
[   20.838089]  uart_set_options+0x138/0x1bc
[   20.838570]  uart_poll_init+0x114/0x16c
[   20.838834]  tty_find_polling_driver+0x158/0x200
[   20.839119]  configure_kgdboc+0xbc/0x1bc
[   20.839380]  param_set_kgdboc_var+0xb8/0x150
[   20.839658]  param_attr_store+0xbc/0x150
[   20.839920]  module_attr_store+0x40/0x58
[   20.840183]  sysfs_kf_write+0x8c/0xa8
[   20.840183]  sysfs_kf_write+0x8c/0xa8
[   20.840440]  kernfs_fop_write+0x154/0x290
[   20.840702]  vfs_write+0xf0/0x278
[   20.840942]  __arm64_sys_write+0x84/0xf4
[   20.841209]  el0_svc_common+0xf4/0x1dc
[   20.841471]  el0_svc_handler+0x98/0xbc
[   20.841713]  el0_svc+0x8/0xc
[   20.842057] Code: bad PC value
[   20.842764] ---[ end trace a8835d7de79aaadf ]---
[   20.843134] Kernel panic - not syncing: Fatal exception
[   20.843515] SMP: stopping secondary CPUs
[   20.844289] Kernel Offset: disabled
[   20.844634] CPU features: 0x0,21806002
[   20.844857] Memory Limit: none
[   20.845172] ---[ end Kernel panic - not syncing: Fatal exception ]---

Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/tty/tty_io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index e6429d419b80..e6c4321d695c 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -354,7 +354,7 @@ struct tty_driver *tty_find_polling_driver(char *name, int *line)
 	mutex_lock(&tty_mutex);
 	/* Search through the tty devices to look for a match */
 	list_for_each_entry(p, &tty_drivers, tty_drivers) {
-		if (strncmp(name, p->name, len) != 0)
+		if (!len || strncmp(name, p->name, len) != 0)
 			continue;
 		stp = str;
 		if (*stp == ',')
-- 
2.17.1

[PATCH AUTOSEL 4.9 06/21] ARM: imx_v6_v7_defconfig: Select CONFIG_TMPFS_POSIX_ACL

[Sasha Levin]

From: Fabio Estevam <fabio.estevam@nxp.com>

[ Upstream commit 35d3cbe84544da74e39e1cec01374092467e3119 ]

Andreas Müller reports:

"Fixes:

| Sep 04 09:05:10 imx6qdl-variscite-som systemd-udevd[220]: Failed to apply ACL on /dev/v4l-subdev0: Operation not supported
| Sep 04 09:05:10 imx6qdl-variscite-som systemd-udevd[224]: Failed to apply ACL on /dev/v4l-subdev1: Operation not supported
| Sep 04 09:05:10 imx6qdl-variscite-som systemd-udevd[215]: Failed to apply ACL on /dev/v4l-subdev10: Operation not supported
| Sep 04 09:05:10 imx6qdl-variscite-som systemd-udevd[228]: Failed to apply ACL on /dev/v4l-subdev2: Operation not supported
| Sep 04 09:05:10 imx6qdl-variscite-som systemd-udevd[232]: Failed to apply ACL on /dev/v4l-subdev5: Operation not supported
| Sep 04 09:05:10 imx6qdl-variscite-som systemd-udevd[217]: Failed to apply ACL on /dev/v4l-subdev11: Operation not supported
| Sep 04 09:05:10 imx6qdl-variscite-som systemd-udevd[214]: Failed to apply ACL on /dev/dri/card1: Operation not supported
| Sep 04 09:05:10 imx6qdl-variscite-som systemd-udevd[216]: Failed to apply ACL on /dev/v4l-subdev8: Operation not supported
| Sep 04 09:05:10 imx6qdl-variscite-som systemd-udevd[226]: Failed to apply ACL on /dev/v4l-subdev9: Operation not supported

and nasty follow-ups: Starting weston from sddm as unpriviledged user fails
with some hints on missing access rights."

Select the CONFIG_TMPFS_POSIX_ACL option to fix these issues.

Reported-by: Andreas Müller <schnitzeltony@gmail.com>
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Acked-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/configs/imx_v6_v7_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/imx_v6_v7_defconfig b/arch/arm/configs/imx_v6_v7_defconfig
index 8ec4dbbb50b0..47c3fb8d4313 100644
--- a/arch/arm/configs/imx_v6_v7_defconfig
+++ b/arch/arm/configs/imx_v6_v7_defconfig
@@ -361,6 +361,7 @@ CONFIG_ZISOFS=y
 CONFIG_UDF_FS=m
 CONFIG_MSDOS_FS=m
 CONFIG_VFAT_FS=y
+CONFIG_TMPFS_POSIX_ACL=y
 CONFIG_JFFS2_FS=y
 CONFIG_UBIFS_FS=y
 CONFIG_NFS_FS=y
-- 
2.17.1

[PATCH AUTOSEL 4.9 07/21] powerpc/nohash: fix undefined behaviour when testing page size support

[Sasha Levin]

From: Daniel Axtens <dja@axtens.net>

[ Upstream commit f5e284803a7206d43e26f9ffcae5de9626d95e37 ]

When enumerating page size definitions to check hardware support,
we construct a constant which is (1U << (def->shift - 10)).

However, the array of page size definitions is only initalised for
various MMU_PAGE_* constants, so it contains a number of 0-initialised
elements with def->shift == 0. This means we end up shifting by a
very large number, which gives the following UBSan splat:

================================================================================
UBSAN: Undefined behaviour in /home/dja/dev/linux/linux/arch/powerpc/mm/tlb_nohash.c:506:21
shift exponent 4294967286 is too large for 32-bit type 'unsigned int'
CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc3-00045-ga604f927b012-dirty #6
Call Trace:
[c00000000101bc20] [c000000000a13d54] .dump_stack+0xa8/0xec (unreliable)
[c00000000101bcb0] [c0000000004f20a8] .ubsan_epilogue+0x18/0x64
[c00000000101bd30] [c0000000004f2b10] .__ubsan_handle_shift_out_of_bounds+0x110/0x1a4
[c00000000101be20] [c000000000d21760] .early_init_mmu+0x1b4/0x5a0
[c00000000101bf10] [c000000000d1ba28] .early_setup+0x100/0x130
[c00000000101bf90] [c000000000000528] start_here_multiplatform+0x68/0x80
================================================================================

Fix this by first checking if the element exists (shift != 0) before
constructing the constant.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/mm/tlb_nohash.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c
index 0b50019505a5..79cf21be8f6e 100644
--- a/arch/powerpc/mm/tlb_nohash.c
+++ b/arch/powerpc/mm/tlb_nohash.c
@@ -481,6 +481,9 @@ static void setup_page_sizes(void)
 		for (psize = 0; psize < MMU_PAGE_COUNT; ++psize) {
 			struct mmu_psize_def *def = &mmu_psize_defs[psize];
 
+			if (!def->shift)
+				continue;
+
 			if (tlb1ps & (1U << (def->shift - 10))) {
 				def->flags |= MMU_PAGE_SIZE_DIRECT;
 
-- 
2.17.1

[PATCH AUTOSEL 4.9 08/21] watchdog: lantiq: update register names to better match spec

[Sasha Levin]

From: Hauke Mehrtens <hauke@hauke-m.de>

[ Upstream commit 1f59f8aff98f200af7a6882184add7b85f5da741 ]

Some of the names of the bits were confusing to me.
Now the bits share the same prefix as the register they are set on.

The LTQ_WDT_CR_PWL register (bits 26:25) is the pre warning limit and it
does not turn anything on. It has 4 possible divers 1/2, 1/4, 1/8 and
1/16, this drivers only uses 1/16.
The LTQ_WDT_CR_CLKDIV register bits(25:24) is only configuring a clock
divers and do not turn any thing on too, all possible values are valid
dividers.
Using the LTQ_WDT_SR prefix is also wrong these bits are used in the
LTQ_WDT_CR registers, SR is the status register which is read only.

This uses GENMASK where it is a mask and it uses shifts when a value is
written to some bits.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/watchdog/lantiq_wdt.c | 36 ++++++++++++++++++-----------------
 1 file changed, 19 insertions(+), 17 deletions(-)

diff --git a/drivers/watchdog/lantiq_wdt.c b/drivers/watchdog/lantiq_wdt.c
index 582f2fa1b8d9..6ab14bd9c1e4 100644
--- a/drivers/watchdog/lantiq_wdt.c
+++ b/drivers/watchdog/lantiq_wdt.c
@@ -12,6 +12,7 @@
 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/miscdevice.h>
+#include <linux/bitops.h>
 #include <linux/watchdog.h>
 #include <linux/of_platform.h>
 #include <linux/uaccess.h>
@@ -28,18 +29,19 @@
  * essentially the following two magic passwords need to be written to allow
  * IO access to the WDT core
  */
-#define LTQ_WDT_PW1		0x00BE0000
-#define LTQ_WDT_PW2		0x00DC0000
+#define LTQ_WDT_CR_PW1		0x00BE0000
+#define LTQ_WDT_CR_PW2		0x00DC0000
+
+#define LTQ_WDT_CR		0x0		/* watchdog control register */
+#define  LTQ_WDT_CR_GEN		BIT(31)		/* enable bit */
+/* Pre-warning limit set to 1/16 of max WDT period */
+#define  LTQ_WDT_CR_PWL		(0x3 << 26)
+/* set clock divider to 0x40000 */
+#define  LTQ_WDT_CR_CLKDIV	(0x3 << 24)
+#define  LTQ_WDT_CR_PW_MASK	GENMASK(23, 16)	/* Password field */
+#define  LTQ_WDT_CR_MAX_TIMEOUT	((1 << 16) - 1)	/* The reload field is 16 bit */
 
-#define LTQ_WDT_CR		0x0	/* watchdog control register */
-#define LTQ_WDT_SR		0x8	/* watchdog status register */
-
-#define LTQ_WDT_SR_EN		(0x1 << 31)	/* enable bit */
-#define LTQ_WDT_SR_PWD		(0x3 << 26)	/* turn on power */
-#define LTQ_WDT_SR_CLKDIV	(0x3 << 24)	/* turn on clock and set */
-						/* divider to 0x40000 */
 #define LTQ_WDT_DIVIDER		0x40000
-#define LTQ_MAX_TIMEOUT		((1 << 16) - 1)	/* the reload field is 16 bit */
 
 static bool nowayout = WATCHDOG_NOWAYOUT;
 
@@ -56,26 +58,26 @@ ltq_wdt_enable(void)
 {
 	unsigned long int timeout = ltq_wdt_timeout *
 			(ltq_io_region_clk_rate / LTQ_WDT_DIVIDER) + 0x1000;
-	if (timeout > LTQ_MAX_TIMEOUT)
-		timeout = LTQ_MAX_TIMEOUT;
+	if (timeout > LTQ_WDT_CR_MAX_TIMEOUT)
+		timeout = LTQ_WDT_CR_MAX_TIMEOUT;
 
 	/* write the first password magic */
-	ltq_w32(LTQ_WDT_PW1, ltq_wdt_membase + LTQ_WDT_CR);
+	ltq_w32(LTQ_WDT_CR_PW1, ltq_wdt_membase + LTQ_WDT_CR);
 	/* write the second magic plus the configuration and new timeout */
-	ltq_w32(LTQ_WDT_SR_EN | LTQ_WDT_SR_PWD | LTQ_WDT_SR_CLKDIV |
-		LTQ_WDT_PW2 | timeout, ltq_wdt_membase + LTQ_WDT_CR);
+	ltq_w32(LTQ_WDT_CR_GEN | LTQ_WDT_CR_PWL | LTQ_WDT_CR_CLKDIV |
+		LTQ_WDT_CR_PW2 | timeout, ltq_wdt_membase + LTQ_WDT_CR);
 }
 
 static void
 ltq_wdt_disable(void)
 {
 	/* write the first password magic */
-	ltq_w32(LTQ_WDT_PW1, ltq_wdt_membase + LTQ_WDT_CR);
+	ltq_w32(LTQ_WDT_CR_PW1, ltq_wdt_membase + LTQ_WDT_CR);
 	/*
 	 * write the second password magic with no config
 	 * this turns the watchdog off
 	 */
-	ltq_w32(LTQ_WDT_PW2, ltq_wdt_membase + LTQ_WDT_CR);
+	ltq_w32(LTQ_WDT_CR_PW2, ltq_wdt_membase + LTQ_WDT_CR);
 }
 
 static ssize_t
-- 
2.17.1

[PATCH AUTOSEL 4.9 09/21] drm/omap: fix memory barrier bug in DMM driver

[Sasha Levin]

From: Tomi Valkeinen <tomi.valkeinen@ti.com>

[ Upstream commit 538f66ba204944470a653a4cccc5f8befdf97c22 ]

A DMM timeout "timed out waiting for done" has been observed on DRA7
devices. The timeout happens rarely, and only when the system is under
heavy load.

Debugging showed that the timeout can be made to happen much more
frequently by optimizing the DMM driver, so that there's almost no code
between writing the last DMM descriptors to RAM, and writing to DMM
register which starts the DMM transaction.

The current theory is that a wmb() does not properly ensure that the
data written to RAM is observable by all the components in the system.

This DMM timeout has caused interesting (and rare) bugs as the error
handling was not functioning properly (the error handling has been fixed
in previous commits):

 * If a DMM timeout happened when a GEM buffer was being pinned for
   display on the screen, a timeout error would be shown, but the driver
   would continue programming DSS HW with broken buffer, leading to
   SYNCLOST floods and possible crashes.

 * If a DMM timeout happened when other user (say, video decoder) was
   pinning a GEM buffer, a timeout would be shown but if the user
   handled the error properly, no other issues followed.

 * If a DMM timeout happened when a GEM buffer was being released, the
   driver does not even notice the error, leading to crashes or hang
   later.

This patch adds wmb() and readl() calls after the last bit is written to
RAM, which should ensure that the execution proceeds only after the data
is actually in RAM, and thus observable by DMM.

The read-back should not be needed. Further study is required to understand
if DMM is somehow special case and read-back is ok, or if DRA7's memory
barriers do not work correctly.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/omapdrm/omap_dmm_tiler.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c b/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
index 7def04049498..6a0b25e0823f 100644
--- a/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
+++ b/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
@@ -273,6 +273,17 @@ static int dmm_txn_commit(struct dmm_txn *txn, bool wait)
 	}
 
 	txn->last_pat->next_pa = 0;
+	/* ensure that the written descriptors are visible to DMM */
+	wmb();
+
+	/*
+	 * NOTE: the wmb() above should be enough, but there seems to be a bug
+	 * in OMAP's memory barrier implementation, which in some rare cases may
+	 * cause the writes not to be observable after wmb().
+	 */
+
+	/* read back to ensure the data is in RAM */
+	readl(&txn->last_pat->next_pa);
 
 	/* write to PAT_DESCR to clear out any pending transaction */
 	dmm_write(dmm, 0x0, reg[PAT_DESCR][engine->id]);
-- 
2.17.1

[PATCH AUTOSEL 4.9 10/21] iio: adc: at91: fix wrong channel number in triggered buffer mode

[Sasha Levin]

From: Eugen Hristev <eugen.hristev@microchip.com>

[ Upstream commit aea835f2dc8a682942b859179c49ad1841a6c8b9 ]

When channels are registered, the hardware channel number is not the
actual iio channel number.
This is because the driver is probed with a certain number of accessible
channels. Some pins are routed and some not, depending on the description of
the board in the DT.
Because of that, channels 0,1,2,3 can correspond to hardware channels
2,3,4,5 for example.
In the buffered triggered case, we need to do the translation accordingly.
Fixed the channel number to stop reading the wrong channel.

Fixes: 0e589d5fb ("ARM: AT91: IIO: Add AT91 ADC driver.")
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/iio/adc/at91_adc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index bbdac07f4aaa..1ba69bbc3142 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -247,12 +247,14 @@ static irqreturn_t at91_adc_trigger_handler(int irq, void *p)
 	struct iio_poll_func *pf = p;
 	struct iio_dev *idev = pf->indio_dev;
 	struct at91_adc_state *st = iio_priv(idev);
+	struct iio_chan_spec const *chan;
 	int i, j = 0;
 
 	for (i = 0; i < idev->masklength; i++) {
 		if (!test_bit(i, idev->active_scan_mask))
 			continue;
-		st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, i));
+		chan = idev->channels + i;
+		st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, chan->channel));
 		j++;
 	}
 
-- 
2.17.1

[PATCH AUTOSEL 4.9 11/21] iio: adc: at91: fix acking DRDY irq on simple conversions

[Sasha Levin]

From: Eugen Hristev <eugen.hristev@microchip.com>

[ Upstream commit bc1b45326223e7e890053cf6266357adfa61942d ]

When doing simple conversions, the driver did not acknowledge the DRDY irq.
If this irq status is not acked, it will be left pending, and as soon as a
trigger is enabled, the irq handler will be called, it doesn't know why
this status has occurred because no channel is pending, and then it will go
int a irq loop and board will hang.
To avoid this situation, read the LCDR after a raw conversion is done.

Fixes: 0e589d5fb ("ARM: AT91: IIO: Add AT91 ADC driver.")
Cc: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/iio/adc/at91_adc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index 1ba69bbc3142..e3e2155b0386 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -280,6 +280,8 @@ static void handle_adc_eoc_trigger(int irq, struct iio_dev *idev)
 		iio_trigger_poll(idev->trig);
 	} else {
 		st->last_value = at91_adc_readl(st, AT91_ADC_CHAN(st, st->chnb));
+		/* Needed to ACK the DRDY interruption */
+		at91_adc_readl(st, AT91_ADC_LCDR);
 		st->done = true;
 		wake_up_interruptible(&st->wq_data_avail);
 	}
-- 
2.17.1

[PATCH AUTOSEL 4.9 12/21] media: pci: cx23885: handle adding to list failure

[Sasha Levin]

From: Nicholas Mc Guire <hofrat@osadl.org>

[ Upstream commit c5d59528e24ad22500347b199d52b9368e686a42 ]

altera_hw_filt_init() which calls append_internal() assumes
that the node was successfully linked in while in fact it can
silently fail. So the call-site needs to set return to -ENOMEM
on append_internal() returning NULL and exit through the err path.

Fixes: 349bcf02e361 ("[media] Altera FPGA based CI driver module")

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/media/pci/cx23885/altera-ci.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/media/pci/cx23885/altera-ci.c b/drivers/media/pci/cx23885/altera-ci.c
index aaf4e46ff3e9..a0c1ff97f905 100644
--- a/drivers/media/pci/cx23885/altera-ci.c
+++ b/drivers/media/pci/cx23885/altera-ci.c
@@ -660,6 +660,10 @@ static int altera_hw_filt_init(struct altera_ci_config *config, int hw_filt_nr)
 		}
 
 		temp_int = append_internal(inter);
+		if (!temp_int) {
+			ret = -ENOMEM;
+			goto err;
+		}
 		inter->filts_used = 1;
 		inter->dev = config->dev;
 		inter->fpga_rw = config->fpga_rw;
@@ -694,6 +698,7 @@ static int altera_hw_filt_init(struct altera_ci_config *config, int hw_filt_nr)
 		     __func__, ret);
 
 	kfree(pid_filt);
+	kfree(inter);
 
 	return ret;
 }
@@ -728,6 +733,10 @@ int altera_ci_init(struct altera_ci_config *config, int ci_nr)
 		}
 
 		temp_int = append_internal(inter);
+		if (!temp_int) {
+			ret = -ENOMEM;
+			goto err;
+		}
 		inter->cis_used = 1;
 		inter->dev = config->dev;
 		inter->fpga_rw = config->fpga_rw;
@@ -796,6 +805,7 @@ int altera_ci_init(struct altera_ci_config *config, int ci_nr)
 	ci_dbg_print("%s: Cannot initialize CI: Error %d.\n", __func__, ret);
 
 	kfree(state);
+	kfree(inter);
 
 	return ret;
 }
-- 
2.17.1

[PATCH AUTOSEL 4.9 13/21] iio: adc: imx25-gcq: Fix leak of device_node in mx25_gcq_setup_cfgs()

[Sasha Levin]

From: Alexey Khoroshilov <khoroshilov@ispras.ru>

[ Upstream commit d3fa21c73c391975488818b085b894c2980ea052 ]

Leaving for_each_child_of_node loop we should release child device node,
if it is not stored for future use.

Found by Linux Driver Verification project (linuxtesting.org).

JC: I'm not sending this as a quick fix as it's been wrong for years,
but good to pick up for stable after the merge window.

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Fixes: 6df2e98c3ea56 ("iio: adc: Add imx25-gcq ADC driver")
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/iio/adc/fsl-imx25-gcq.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/iio/adc/fsl-imx25-gcq.c b/drivers/iio/adc/fsl-imx25-gcq.c
index ea264fa9e567..929c617db364 100644
--- a/drivers/iio/adc/fsl-imx25-gcq.c
+++ b/drivers/iio/adc/fsl-imx25-gcq.c
@@ -209,12 +209,14 @@ static int mx25_gcq_setup_cfgs(struct platform_device *pdev,
 		ret = of_property_read_u32(child, "reg", &reg);
 		if (ret) {
 			dev_err(dev, "Failed to get reg property\n");
+			of_node_put(child);
 			return ret;
 		}
 
 		if (reg >= MX25_NUM_CFGS) {
 			dev_err(dev,
 				"reg value is greater than the number of available configuration registers\n");
+			of_node_put(child);
 			return -EINVAL;
 		}
 
@@ -228,6 +230,7 @@ static int mx25_gcq_setup_cfgs(struct platform_device *pdev,
 			if (IS_ERR(priv->vref[refp])) {
 				dev_err(dev, "Error, trying to use external voltage reference without a vref-%s regulator.",
 					mx25_gcq_refp_names[refp]);
+				of_node_put(child);
 				return PTR_ERR(priv->vref[refp]);
 			}
 			priv->channel_vref_mv[reg] =
@@ -240,6 +243,7 @@ static int mx25_gcq_setup_cfgs(struct platform_device *pdev,
 			break;
 		default:
 			dev_err(dev, "Invalid positive reference %d\n", refp);
+			of_node_put(child);
 			return -EINVAL;
 		}
 
@@ -254,10 +258,12 @@ static int mx25_gcq_setup_cfgs(struct platform_device *pdev,
 
 		if ((refp & MX25_ADCQ_CFG_REFP_MASK) != refp) {
 			dev_err(dev, "Invalid fsl,adc-refp property value\n");
+			of_node_put(child);
 			return -EINVAL;
 		}
 		if ((refn & MX25_ADCQ_CFG_REFN_MASK) != refn) {
 			dev_err(dev, "Invalid fsl,adc-refn property value\n");
+			of_node_put(child);
 			return -EINVAL;
 		}
 
-- 
2.17.1

[PATCH AUTOSEL 4.9 14/21] MIPS: kexec: Mark CPU offline before disabling local IRQ

[Sasha Levin]

From: Dengcheng Zhu <dzhu@wavecomp.com>

[ Upstream commit dc57aaf95a516f70e2d527d8287a0332c481a226 ]

After changing CPU online status, it will not be sent any IPIs such as in
__flush_cache_all() on software coherency systems. Do this before disabling
local IRQ.

Signed-off-by: Dengcheng Zhu <dzhu@wavecomp.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20571/
Cc: pburton@wavecomp.com
Cc: ralf@linux-mips.org
Cc: linux-mips@linux-mips.org
Cc: rachel.mozes@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/mips/kernel/crash.c         | 3 +++
 arch/mips/kernel/machine_kexec.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/arch/mips/kernel/crash.c b/arch/mips/kernel/crash.c
index 1723b1762297..e757f36cea6f 100644
--- a/arch/mips/kernel/crash.c
+++ b/arch/mips/kernel/crash.c
@@ -34,6 +34,9 @@ static void crash_shutdown_secondary(void *passed_regs)
 	if (!cpu_online(cpu))
 		return;
 
+	/* We won't be sent IPIs any more. */
+	set_cpu_online(cpu, false);
+
 	local_irq_disable();
 	if (!cpumask_test_cpu(cpu, &cpus_in_crash))
 		crash_save_cpu(regs, cpu);
diff --git a/arch/mips/kernel/machine_kexec.c b/arch/mips/kernel/machine_kexec.c
index 59725204105c..32b567e88b02 100644
--- a/arch/mips/kernel/machine_kexec.c
+++ b/arch/mips/kernel/machine_kexec.c
@@ -96,6 +96,9 @@ machine_kexec(struct kimage *image)
 			*ptr = (unsigned long) phys_to_virt(*ptr);
 	}
 
+	/* Mark offline BEFORE disabling local irq. */
+	set_cpu_online(smp_processor_id(), false);
+
 	/*
 	 * we do not want to be bothered.
 	 */
-- 
2.17.1

[PATCH AUTOSEL 4.9 15/21] powerpc/boot: Ensure _zimage_start is a weak symbol

[Sasha Levin]

From: Joel Stanley <joel@jms.id.au>

[ Upstream commit ee9d21b3b3583712029a0db65a4b7c081d08d3b3 ]

When building with clang crt0's _zimage_start is not marked weak, which
breaks the build when linking the kernel image:

 $ objdump -t arch/powerpc/boot/crt0.o |grep _zimage_start$
 0000000000000058 g       .text  0000000000000000 _zimage_start

 ld: arch/powerpc/boot/wrapper.a(crt0.o): in function '_zimage_start':
 (.text+0x58): multiple definition of '_zimage_start';
 arch/powerpc/boot/pseries-head.o:(.text+0x0): first defined here

Clang requires the .weak directive to appear after the symbol is
declared. The binutils manual says:

 This directive sets the weak attribute on the comma separated list of
 symbol names. If the symbols do not already exist, they will be
 created.

So it appears this is different with clang. The only reference I could
see for this was an OpenBSD mailing list post[1].

Changing it to be after the declaration fixes building with Clang, and
still works with GCC.

 $ objdump -t arch/powerpc/boot/crt0.o |grep _zimage_start$
 0000000000000058  w      .text	0000000000000000 _zimage_start

Reported to clang as https://bugs.llvm.org/show_bug.cgi?id=38921

[1] https://groups.google.com/forum/#!topic/fa.openbsd.tech/PAgKKen2YCY

Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/boot/crt0.S | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/boot/crt0.S b/arch/powerpc/boot/crt0.S
index 12866ccb5694..5c2199857aa8 100644
--- a/arch/powerpc/boot/crt0.S
+++ b/arch/powerpc/boot/crt0.S
@@ -47,8 +47,10 @@ p_end:		.long	_end
 p_pstack:	.long	_platform_stack_top
 #endif
 
-	.weak	_zimage_start
 	.globl	_zimage_start
+	/* Clang appears to require the .weak directive to be after the symbol
+	 * is defined. See https://bugs.llvm.org/show_bug.cgi?id=38921  */
+	.weak	_zimage_start
 _zimage_start:
 	.globl	_zimage_start_lib
 _zimage_start_lib:
-- 
2.17.1

[PATCH AUTOSEL 4.9 16/21] MIPS/PCI: Call pcie_bus_configure_settings() to set MPS/MRRS

[Sasha Levin]

From: Huacai Chen <chenhc@lemote.com>

[ Upstream commit 2794f688b2c336e0da85e9f91fed33febbd9f54a ]

Call pcie_bus_configure_settings() on MIPS, like for other platforms.
The function pcie_bus_configure_settings() makes sure the MPS (Max
Payload Size) across the bus is uniform and provides the ability to
tune the MRSS (Max Read Request Size) and MPS (Max Payload Size) to
higher performance values. Some devices will not operate properly if
these aren't set correctly because the firmware doesn't always do it.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/20649/
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Cc: Huacai Chen <chenhuacai@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/mips/pci/pci-legacy.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/mips/pci/pci-legacy.c b/arch/mips/pci/pci-legacy.c
index 014649be158d..2d6886f09ba3 100644
--- a/arch/mips/pci/pci-legacy.c
+++ b/arch/mips/pci/pci-legacy.c
@@ -116,8 +116,12 @@ static void pcibios_scanbus(struct pci_controller *hose)
 	if (pci_has_flag(PCI_PROBE_ONLY)) {
 		pci_bus_claim_resources(bus);
 	} else {
+		struct pci_bus *child;
+
 		pci_bus_size_bridges(bus);
 		pci_bus_assign_resources(bus);
+		list_for_each_entry(child, &bus->children, node)
+			pcie_bus_configure_settings(child);
 	}
 	pci_bus_add_devices(bus);
 }
-- 
2.17.1

[PATCH AUTOSEL 4.9 17/21] sc16is7xx: Fix for multi-channel stall

[Sasha Levin]

From: Phil Elwell <phil@raspberrypi.org>

[ Upstream commit 8344498721059754e09d30fe255a12dab8fb03ef ]

The SC16IS752 is a dual-channel device. The two channels are largely
independent, but the IRQ signals are wired together as an open-drain,
active low signal which will be driven low while either of the
channels requires attention, which can be for significant periods of
time until operations complete and the interrupt can be acknowledged.
In that respect it is should be treated as a true level-sensitive IRQ.

The kernel, however, needs to be able to exit interrupt context in
order to use I2C or SPI to access the device registers (which may
involve sleeping).  Therefore the interrupt needs to be masked out or
paused in some way.

The usual way to manage sleeping from within an interrupt handler
is to use a threaded interrupt handler - a regular interrupt routine
does the minimum amount of work needed to triage the interrupt before
waking the interrupt service thread. If the threaded IRQ is marked as
IRQF_ONESHOT the kernel will automatically mask out the interrupt
until the thread runs to completion. The sc16is7xx driver used to
use a threaded IRQ, but a patch switched to using a kthread_worker
in order to set realtime priorities on the handler thread and for
other optimisations. The end result is non-threaded IRQ that
schedules some work then returns IRQ_HANDLED, making the kernel
think that all IRQ processing has completed.

The work-around to prevent a constant stream of interrupts is to
mark the interrupt as edge-sensitive rather than level-sensitive,
but interpreting an active-low source as a falling-edge source
requires care to prevent a total cessation of interrupts. Whereas
an edge-triggering source will generate a new edge for every interrupt
condition a level-triggering source will keep the signal at the
interrupting level until it no longer requires attention; in other
words, the host won't see another edge until all interrupt conditions
are cleared. It is therefore vital that the interrupt handler does not
exit with an outstanding interrupt condition, otherwise the kernel
will not receive another interrupt unless some other operation causes
the interrupt state on the device to be cleared.

The existing sc16is7xx driver has a very simple interrupt "thread"
(kthread_work job) that processes interrupts on each channel in turn
until there are no more. If both channels are active and the first
channel starts interrupting while the handler for the second channel
is running then it will not be detected and an IRQ stall ensues. This
could be handled easily if there was a shared IRQ status register, or
a convenient way to determine if the IRQ had been deasserted for any
length of time, but both appear to be lacking.

Avoid this problem (or at least make it much less likely to happen)
by reducing the granularity of per-channel interrupt processing
to one condition per iteration, only exiting the overall loop when
both channels are no longer interrupting.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/tty/serial/sc16is7xx.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 793395451982..ea6b62cece88 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -661,7 +661,7 @@ static void sc16is7xx_handle_tx(struct uart_port *port)
 		uart_write_wakeup(port);
 }
 
-static void sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
+static bool sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
 {
 	struct uart_port *port = &s->p[portno].port;
 
@@ -670,7 +670,7 @@ static void sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
 
 		iir = sc16is7xx_port_read(port, SC16IS7XX_IIR_REG);
 		if (iir & SC16IS7XX_IIR_NO_INT_BIT)
-			break;
+			return false;
 
 		iir &= SC16IS7XX_IIR_ID_MASK;
 
@@ -692,16 +692,23 @@ static void sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
 					    port->line, iir);
 			break;
 		}
-	} while (1);
+	} while (0);
+	return true;
 }
 
 static void sc16is7xx_ist(struct kthread_work *ws)
 {
 	struct sc16is7xx_port *s = to_sc16is7xx_port(ws, irq_work);
-	int i;
 
-	for (i = 0; i < s->devtype->nr_uart; ++i)
-		sc16is7xx_port_irq(s, i);
+	while (1) {
+		bool keep_polling = false;
+		int i;
+
+		for (i = 0; i < s->devtype->nr_uart; ++i)
+			keep_polling |= sc16is7xx_port_irq(s, i);
+		if (!keep_polling)
+			break;
+	}
 }
 
 static irqreturn_t sc16is7xx_irq(int irq, void *dev_id)
-- 
2.17.1

[PATCH AUTOSEL 4.9 18/21] media: tvp5150: fix width alignment during set_selection()

[Sasha Levin]

From: Marco Felsch <m.felsch@pengutronix.de>

[ Upstream commit bd24db04101f45a9c1d874fe21b0c7eab7bcadec ]

The driver ignored the width alignment which exists due to the UYVY
colorspace format. Fix the width alignment and make use of the the
provided v4l2 helper function to set the width, height and all
alignments in one.

Fixes: 963ddc63e20d ("[media] media: tvp5150: Add cropping support")

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/media/i2c/tvp5150.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/media/i2c/tvp5150.c b/drivers/media/i2c/tvp5150.c
index 59aa4dafb60b..172198178343 100644
--- a/drivers/media/i2c/tvp5150.c
+++ b/drivers/media/i2c/tvp5150.c
@@ -897,9 +897,6 @@ static int tvp5150_set_selection(struct v4l2_subdev *sd,
 
 	/* tvp5150 has some special limits */
 	rect.left = clamp(rect.left, 0, TVP5150_MAX_CROP_LEFT);
-	rect.width = clamp_t(unsigned int, rect.width,
-			     TVP5150_H_MAX - TVP5150_MAX_CROP_LEFT - rect.left,
-			     TVP5150_H_MAX - rect.left);
 	rect.top = clamp(rect.top, 0, TVP5150_MAX_CROP_TOP);
 
 	/* Calculate height based on current standard */
@@ -913,9 +910,16 @@ static int tvp5150_set_selection(struct v4l2_subdev *sd,
 	else
 		hmax = TVP5150_V_MAX_OTHERS;
 
-	rect.height = clamp_t(unsigned int, rect.height,
+	/*
+	 * alignments:
+	 *  - width = 2 due to UYVY colorspace
+	 *  - height, image = no special alignment
+	 */
+	v4l_bound_align_image(&rect.width,
+			      TVP5150_H_MAX - TVP5150_MAX_CROP_LEFT - rect.left,
+			      TVP5150_H_MAX - rect.left, 1, &rect.height,
 			      hmax - TVP5150_MAX_CROP_TOP - rect.top,
-			      hmax - rect.top);
+			      hmax - rect.top, 0, 0);
 
 	tvp5150_write(sd, TVP5150_VERT_BLANKING_START, rect.top);
 	tvp5150_write(sd, TVP5150_VERT_BLANKING_STOP,
-- 
2.17.1

[PATCH AUTOSEL 4.9 19/21] powerpc/selftests: Wait all threads to join

[Sasha Levin]

From: Breno Leitao <leitao@debian.org>

[ Upstream commit 693b31b2fc1636f0aa7af53136d3b49f6ad9ff39 ]

Test tm-tmspr might exit before all threads stop executing, because it just
waits for the very last thread to join before proceeding/exiting.

This patch makes sure that all threads that were created will join before
proceeding/exiting.

This patch also guarantees that the amount of threads being created is equal
to thread_num.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 tools/testing/selftests/powerpc/tm/tm-tmspr.c | 27 ++++++++++++-------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/tools/testing/selftests/powerpc/tm/tm-tmspr.c b/tools/testing/selftests/powerpc/tm/tm-tmspr.c
index 2bda81c7bf23..df1d7d4b1c89 100644
--- a/tools/testing/selftests/powerpc/tm/tm-tmspr.c
+++ b/tools/testing/selftests/powerpc/tm/tm-tmspr.c
@@ -98,7 +98,7 @@ void texasr(void *in)
 
 int test_tmspr()
 {
-	pthread_t 	thread;
+	pthread_t	*thread;
 	int	   	thread_num;
 	unsigned long	i;
 
@@ -107,21 +107,28 @@ int test_tmspr()
 	/* To cause some context switching */
 	thread_num = 10 * sysconf(_SC_NPROCESSORS_ONLN);
 
+	thread = malloc(thread_num * sizeof(pthread_t));
+	if (thread == NULL)
+		return EXIT_FAILURE;
+
 	/* Test TFIAR and TFHAR */
-	for (i = 0 ; i < thread_num ; i += 2){
-		if (pthread_create(&thread, NULL, (void*)tfiar_tfhar, (void *)i))
+	for (i = 0; i < thread_num; i += 2) {
+		if (pthread_create(&thread[i], NULL, (void *)tfiar_tfhar,
+				   (void *)i))
 			return EXIT_FAILURE;
 	}
-	if (pthread_join(thread, NULL) != 0)
-		return EXIT_FAILURE;
-
 	/* Test TEXASR */
-	for (i = 0 ; i < thread_num ; i++){
-		if (pthread_create(&thread, NULL, (void*)texasr, (void *)i))
+	for (i = 1; i < thread_num; i += 2) {
+		if (pthread_create(&thread[i], NULL, (void *)texasr, (void *)i))
 			return EXIT_FAILURE;
 	}
-	if (pthread_join(thread, NULL) != 0)
-		return EXIT_FAILURE;
+
+	for (i = 0; i < thread_num; i++) {
+		if (pthread_join(thread[i], NULL) != 0)
+			return EXIT_FAILURE;
+	}
+
+	free(thread);
 
 	if (passed)
 		return 0;
-- 
2.17.1

[PATCH AUTOSEL 4.9 20/21] 9p locks: fix glock.client_id leak in do_lock

[Sasha Levin]

From: Dominique Martinet <dominique.martinet@cea.fr>

[ Upstream commit b4dc44b3cac9e8327e0655f530ed0c46f2e6214c ]

the 9p client code overwrites our glock.client_id pointing to a static
buffer by an allocated string holding the network provided value which
we do not care about; free and reset the value as appropriate.

This is almost identical to the leak in v9fs_file_getlock() fixed by
Al Viro in commit ce85dd58ad5a6 ("9p: we are leaking glock.client_id
in v9fs_file_getlock()"), which was returned as an error by a coverity
false positive -- while we are here attempt to make the code slightly
more robust to future change of the net/9p/client code and hopefully
more clear to coverity that there is no problem.

Link: http://lkml.kernel.org/r/1536339057-21974-5-git-send-email-asmadeus@codewreck.org
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/9p/vfs_file.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index d7b78d531e63..398a3eddb2df 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -204,6 +204,14 @@ static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
 			break;
 		if (schedule_timeout_interruptible(P9_LOCK_TIMEOUT) != 0)
 			break;
+		/*
+		 * p9_client_lock_dotl overwrites flock.client_id with the
+		 * server message, free and reuse the client name
+		 */
+		if (flock.client_id != fid->clnt->name) {
+			kfree(flock.client_id);
+			flock.client_id = fid->clnt->name;
+		}
 	}
 
 	/* map 9p status to VFS status */
@@ -235,6 +243,8 @@ static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
 		locks_lock_file_wait(filp, fl);
 		fl->fl_type = fl_type;
 	}
+	if (flock.client_id != fid->clnt->name)
+		kfree(flock.client_id);
 out:
 	return res;
 }
@@ -269,7 +279,7 @@ static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
 
 	res = p9_client_getlock_dotl(fid, &glock);
 	if (res < 0)
-		return res;
+		goto out;
 	/* map 9p lock type to os lock type */
 	switch (glock.type) {
 	case P9_LOCK_TYPE_RDLCK:
@@ -290,7 +300,9 @@ static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
 			fl->fl_end = glock.start + glock.length - 1;
 		fl->fl_pid = glock.proc_id;
 	}
-	kfree(glock.client_id);
+out:
+	if (glock.client_id != fid->clnt->name)
+		kfree(glock.client_id);
 	return res;
 }
 
-- 
2.17.1

[PATCH AUTOSEL 4.9 21/21] 9p: clear dangling pointers in p9stat_free

[Sasha Levin]

From: Dominique Martinet <dominique.martinet@cea.fr>

[ Upstream commit 62e3941776fea8678bb8120607039410b1b61a65 ]

p9stat_free is more of a cleanup function than a 'free' function as it
only frees the content of the struct; there are chances of use-after-free
if it is improperly used (e.g. p9stat_free called twice as it used to be
possible to)

Clearing dangling pointers makes the function idempotent and safer to use.

Link: http://lkml.kernel.org/r/1535410108-20650-2-git-send-email-asmadeus@codewreck.org
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Reported-by: syzbot+d4252148d198410b864f@syzkaller.appspotmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/9p/protocol.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/9p/protocol.c b/net/9p/protocol.c
index 16d287565987..145f80518064 100644
--- a/net/9p/protocol.c
+++ b/net/9p/protocol.c
@@ -46,10 +46,15 @@ p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
 void p9stat_free(struct p9_wstat *stbuf)
 {
 	kfree(stbuf->name);
+	stbuf->name = NULL;
 	kfree(stbuf->uid);
+	stbuf->uid = NULL;
 	kfree(stbuf->gid);
+	stbuf->gid = NULL;
 	kfree(stbuf->muid);
+	stbuf->muid = NULL;
 	kfree(stbuf->extension);
+	stbuf->extension = NULL;
 }
 EXPORT_SYMBOL(p9stat_free);
 
-- 
2.17.1