3.18.122-stable review

This is the start of the stable review cycle for the 3.18.122 release. There are 29 patches in this series, all will be posted as a response to this one. If anyone has any issues with these being applied, please let me know.

Responses should be made by Sun Sep 9 21:08:52 UTC 2018. Anything received after that time might be too late.

The whole patch series can be found in one patch at:

	https://www.kernel.org/pub/linux/kernel/v3.x/stable-review/patch-3.18.122-rc1.gz

or in the git tree and branch at:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-3.18.y
and the diffstat can be found below.

thanks,

greg k-h

-------------
Pseudo-Shortlog of commits:

Greg Kroah-Hartman <[email protected]>

    Linux 3.18.122-rc1

Shan Hai <[email protected]>

    bcache: release dc->writeback_lock properly in bch_writeback_thread()

Christian Brauner <[email protected]>
getxattr: use correct xattr length

Mikulas Patocka <[email protected]>
udlfb: set optimal write delay

Mikulas Patocka <[email protected]>
fb: fix lost console when the user unplugs a USB adapter

Vignesh R <[email protected]>
pwm: tiehrpwm: Fix disabling of output of PWMs

Richard Weinberger <[email protected]>
ubifs: Fix synced_i_size calculation for xattr inodes

Richard Weinberger <[email protected]>
Revert "UBIFS: Fix potential integer overflow in allocation"

Richard Weinberger <[email protected]>
ubifs: Fix memory leak in lprobs self-check

Jann Horn <[email protected]>
userns: move user access out of the mutex

Eric W. Biederman <[email protected]>
userns; Correct the comment in map_write

Jann Horn <[email protected]>
sys: don't hold uts_sem while accessing userspace memory

Al Viro <[email protected]>
osf_getdomainname(): use copy_to_user()

Peter Zijlstra <[email protected]>
mm/tlb: Remove tlb_remove_table() non-concurrent condition

Jon Hunter <[email protected]>
ARM: tegra: Fix Tegra30 Cardhu PCA954x reset

Dan Carpenter <[email protected]>
pnfs/blocklayout: off by one in bl_map_stripe()

Tomas Bortoli <[email protected]>
9p: fix multiple NULL-pointer-dereferences

Steven Rostedt (VMware) <[email protected]>
uprobes: Use synchronize_rcu() not synchronize_sched()

Snild Dolkow <[email protected]>
kthread, tracing: Don't expose half-written comm when creating kthreads

Steven Rostedt (VMware) <[email protected]>
tracing/blktrace: Fix to allow setting same value

Steven Rostedt (VMware) <[email protected]>
tracing: Do not call start/stop() functions when tracing_on does not change

Lars-Peter Clausen <[email protected]>
iio: ad9523: Fix return value for ad952x_store()

Lars-Peter Clausen <[email protected]>
iio: ad9523: Fix displayed phase

Mike Snitzer <[email protected]>
dm cache metadata: save in-core policy_hint_size to on-disk superblock

Tomas Bortoli <[email protected]>
net/9p/trans_fd.c: fix race-condition by flushing workqueue before the kfree()

Tomas Bortoli <[email protected]>
net/9p/client.c: version pointer uninitialized

jiangyiwen <[email protected]>
9p/virtio: fix off-by-one error in sg list bounds check

Mahesh Salgaonkar <[email protected]>
powerpc/pseries: Fix endianness while restoring of r3 in MCE handler.

Hari Bathini <[email protected]>
powerpc/fadump: handle crash memory ranges array index overflow

Bartosz Golaszewski <[email protected]>
spi: davinci: fix a NULL pointer dereference

-------------

Diffstat:

 Makefile                              |  4 +-
 arch/alpha/kernel/osf_sys.c           | 64 +++++++++++------------
 arch/arm/boot/dts/tegra30-cardhu.dtsi |  1 +
 arch/powerpc/include/asm/fadump.h     |  3 --
 arch/powerpc/kernel/fadump.c          | 91 +++++++++++++++++++++++++++------
 arch/powerpc/platforms/pseries/ras.c  |  2 +-
 arch/sparc/kernel/sys_sparc_32.c      | 22 ++++----
 arch/sparc/kernel/sys_sparc_64.c      | 20 +++++---
 drivers/iio/frequency/ad9523.c        |  4 +-
 drivers/md/bcache/writeback.c         |  4 +-
 drivers/md/dm-cache-metadata.c        |  3 +-
 drivers/pwm/pwm-tiehrpwm.c            |  2 +
 drivers/spi/spi-davinci.c             |  2 +-
 drivers/video/fbdev/core/fbmem.c      | 38 +++++++++++---
 fs/nfs/blocklayout/dev.c              |  2 +-
 fs/ubifs/journal.c                    |  7 ++-
 fs/ubifs/lprops.c                     |  8 +--
 fs/xattr.c                            |  2 +-
 include/video/udlfb.h                 |  2 +-
 kernel/kthread.c                      |  8 ++-
 kernel/sys.c                          | 95 +++++++++++++++++------------------
 kernel/trace/blktrace.c               |  4 ++
 kernel/trace/trace.c                  |  4 +-
 kernel/trace/trace_uprobe.c           |  2 +-
 kernel/user_namespace.c               | 22 ++++----
 kernel/utsname_sysctl.c               | 41 +++++++++------
 mm/memory.c                           |  9 ----
 net/9p/client.c                       |  2 +-
 net/9p/trans_fd.c                     |  7 ++-
 net/9p/trans_rdma.c                   |  3 ++
 net/9p/trans_virtio.c                 |  6 ++-
 31 files changed, 299 insertions(+), 185 deletions(-)

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Bartosz Golaszewski <[email protected]>

commit 563a53f3906a6b43692498e5b3ae891fac93a4af upstream.

On non-OF systems spi->controlled_data may be NULL. This causes a NULL pointer derefence on dm365-evm.

---
 drivers/spi/spi-davinci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -230,7 +230,7 @@ static void davinci_spi_chipselect(struc
 	}
 
 	/* program delay transfers if tx_delay is non zero */
-	if (spicfg->wdelay)
+	if (spicfg && spicfg->wdelay)
 		spidat1 |= SPIDAT1_WDEL;
 
 	/*

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Hari Bathini <[email protected]>

commit 1bd6a1c4b80a28d975287630644e6b47d0f977a5 upstream.

Crash memory ranges is an array of memory ranges of the crashing kernel to be exported as a dump via /proc/vmcore file. The size of the array is set based on INIT_MEMBLOCK_REGIONS, which works alright in most cases where memblock memory regions count is less than INIT_MEMBLOCK_REGIONS value. But this count can grow beyond INIT_MEMBLOCK_REGIONS value since commit 142b45a72e22 ("memblock: Add array resizing support").

On large memory systems with a few DLPAR operations, the memblock memory regions count could be larger than INIT_MEMBLOCK_REGIONS value. On such systems, registering fadump results in crash or other system failures like below:

task: c00007f39a290010 ti: c00000000b738000 task.ti: c00000000b738000
NIP: c000000000047df4 LR: c0000000000f9e58 CTR: c00000000010f180
REGS: c00000000b73b570 TRAP: 0300 Tainted: G L X (4.4.140+)
MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 22004484 XER: 20000000
CFAR: c000000000008500 DAR: 000007a450000000 DSISR: 40000000 SOFTE: 0
...
NIP [c000000000047df4] smp_send_reschedule+0x24/0x80
LR [c0000000000f9e58] resched_curr+0x138/0x160

  Call Trace:
    resched_curr+0x138/0x160 (unreliable)
    check_preempt_curr+0xc8/0xf0
    ttwu_do_wakeup+0x38/0x150
    try_to_wake_up+0x224/0x4d0
    __wake_up_common+0x94/0x100
    ep_poll_callback+0xac/0x1c0
    __wake_up_common+0x94/0x100
    __wake_up_sync_key+0x70/0xa0
    sock_def_readable+0x58/0xa0
    unix_stream_sendmsg+0x2dc/0x4c0
    sock_sendmsg+0x68/0xa0
    ___sys_sendmsg+0x2cc/0x2e0
    __sys_sendmsg+0x5c/0xc0
    SyS_socketcall+0x36c/0x3f0
    system_call+0x3c/0x100

as array index overflow is not checked for while setting up crash memory ranges causing memory corruption. To resolve this issue, dynamically allocate memory for crash memory ranges and resize it incrementally, in units of pagesize, on hitting array size limit.

---
 arch/powerpc/include/asm/fadump.h |    3 -
 arch/powerpc/kernel/fadump.c      |   91 ++++++++++++++++++++++++++++++++------
 2 files changed, 77 insertions(+), 17 deletions(-)

@@ -194,9 +194,6 @@ struct fadump_crash_info_header {
 	struct cpumask	cpu_online_mask;
 };
 
-/* Crash memory ranges */
-#define INIT_CRASHMEM_RANGES	(INIT_MEMBLOCK_REGIONS + 2)
-
 struct fad_crash_memory_ranges {
 	unsigned long long	base;
 	unsigned long long	size;

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mahesh Salgaonkar <[email protected]>

commit cd813e1cd7122f2c261dce5b54d1e0c97f80e1a5 upstream.

During Machine Check interrupt on pseries platform, register r3 points RTAS extended event log passed by hypervisor. Since hypervisor uses r3 to pass pointer to rtas log, it stores the original r3 value at the start of the memory (first 8 bytes) pointed by r3. Since hypervisor stores this info and rtas log is in BE format, linux should make sure to restore r3 value in correct endian format.

Without this patch when MCE handler, after recovery, returns to code that that caused the MCE may end up with Data SLB access interrupt for invalid address followed by kernel panic or hang.

Severe Machine check interrupt [Recovered]

    NIP [d00000000ca301b8]: init_module+0x1b8/0x338 [bork_kernel]
    Initiator: CPU
    Error type: SLB [Multihit]
      Effective address: d00000000ca70000
  cpu 0xa: Vector: 380 (Data SLB Access) at [c0000000fc7775b0]
      pc: c0000000009694c0: vsnprintf+0x80/0x480
      lr: c0000000009698e0: vscnprintf+0x20/0x60
      sp: c0000000fc777830
     msr: 8000000002009033
     dar: a803a30c000000d0
    current = 0xc00000000bc9ef00
    paca    = 0xc00000001eca5c00	 softe: 3	 irq_happened: 0x01
      pid   = 8860, comm = insmod
  vscnprintf+0x20/0x60
  vprintk_emit+0xb4/0x4b0
  vprintk_func+0x5c/0xd0
  printk+0x38/0x4c
  init_module+0x1c0/0x338 [bork_kernel]
  do_one_initcall+0x54/0x230
  do_init_module+0x8c/0x248
  load_module+0x12b8/0x15b0
  sys_finit_module+0xa8/0x110
  system_call+0x58/0x6c
  --- Exception: c00 (System Call) at 00007fff8bda0644
  SP (7fffdfbfe980) is in userspace

This patch fixes this issue.

---
 arch/powerpc/platforms/pseries/ras.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -298,7 +298,7 @@ static struct rtas_error_log *fwnmi_get_
 	}
 
 	savep = __va(regs->gpr[3]);
-	regs->gpr[3] = savep[0];	/* restore original r3 */
+	regs->gpr[3] = be64_to_cpu(savep[0]);	/* restore original r3 */
 
 	/* If it isn't an extended log we can use the per cpu 64bit buffer */
 	h = (struct rtas_error_log *)&savep[1];

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: jiangyiwen <[email protected]>

commit 23cba9cbde0bba05d772b335fe5f66aa82b9ad19 upstream.

Because the value of limit is VIRTQUEUE_NUM, if index is equal to limit, it will cause sg array out of bounds, so correct the judgement of BUG_ON.

---
 net/9p/trans_virtio.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

@@ -192,7 +192,7 @@ static int pack_sg_list(struct scatterli
 		s = rest_of_page(data);
 		if (s > count)
 			s = count;
-		BUG_ON(index > limit);
+		BUG_ON(index >= limit);
 		/* Make sure we don't terminate early. */
 		sg_unmark_end(&sg[index]);
 		sg_set_buf(&sg[index++], data, s);

@@ -238,6 +238,7 @@ pack_sg_list_p(struct scatterlist *sg, i
 		s = rest_of_page(data);
 		if (s > count)
 			s = count;
+		BUG_ON(index >= limit);
 		/* Make sure we don't terminate early. */
 		sg_unmark_end(&sg[index]);
 		sg_set_page(&sg[index++], pdata[i++], s, data_off);

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Tomas Bortoli <[email protected]>

commit 7913690dcc5e18e235769fd87c34143072f5dbea upstream.

The p9_client_version() does not initialize the version pointer. If the call to p9pdu_readf() returns an error and version has not been allocated in p9pdu_readf(), then the program will jump to the "error" label and will try to free the version pointer. If version is not initialized, free() will be called with uninitialized, garbage data and will provoke a crash.

---
 net/9p/client.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -938,7 +938,7 @@ static int p9_client_version(struct p9_c
 {
 	int err = 0;
 	struct p9_req_t *req;
-	char *version;
+	char *version = NULL;
 	int msize;
 
 	p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Tomas Bortoli <[email protected]>

commit 430ac66eb4c5b5c4eb846b78ebf65747510b30f1 upstream.

The patch adds the flush in p9_mux_poll_stop() as it the function used by p9_conn_destroy(), in turn called by p9_fd_close() to stop the async polling associated with the data regarding the connection.

To: Eric Van Hensbergen <[email protected]>
To: Ron Minnich <[email protected]>
To: Latchesar Ionkov <[email protected]>

---
 net/9p/trans_fd.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -185,6 +185,8 @@ static void p9_mux_poll_stop(struct p9_c
 	spin_lock_irqsave(&p9_poll_lock, flags);
 	list_del_init(&m->poll_pending_link);
 	spin_unlock_irqrestore(&p9_poll_lock, flags);
+
+	flush_work(&p9_poll_work);
 }
 
 /**

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mike Snitzer <[email protected]>

commit fd2fa95416188a767a63979296fa3e169a9ef5ec upstream.

policy_hint_size starts as 0 during __write_initial_superblock(). It isn't until the policy is loaded that policy_hint_size is set in-core (cmd->policy_hint_size). But it never got recorded in the on-disk superblock because __commit_transaction() didn't deal with transfering the in-core cmd->policy_hint_size to the on-disk superblock.

The in-core cmd->policy_hint_size gets initialized by metadata_open()'s __begin_transaction_flags() which re-reads all superblock fields. Because the superblock's policy_hint_size was never properly stored, when the cache was created, hints_array_available() would always return false when re-activating a previously created cache. This means __load_mappings() always considered the hints invalid and never made use of the hints (these hints served to optimize).

Another detremental side-effect of this oversight is the cache_check utility would fail with: "invalid hint width: 0"

---
 drivers/md/dm-cache-metadata.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

@@ -324,7 +324,7 @@ static int __write_initial_superblock(st
 	disk_super->version = cpu_to_le32(MAX_CACHE_VERSION);
 	memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name));
 	memset(disk_super->policy_version, 0, sizeof(disk_super->policy_version));
-	disk_super->policy_hint_size = 0;
+	disk_super->policy_hint_size = cpu_to_le32(0);
 
 	__copy_sm_root(cmd, disk_super);
 

@@ -635,6 +635,7 @@ static int __commit_transaction(struct d
 	disk_super->policy_version[0] = cpu_to_le32(cmd->policy_version[0]);
 	disk_super->policy_version[1] = cpu_to_le32(cmd->policy_version[1]);
 	disk_super->policy_version[2] = cpu_to_le32(cmd->policy_version[2]);
+	disk_super->policy_hint_size = cpu_to_le32(cmd->policy_hint_size);
 
 	disk_super->read_hits = cpu_to_le32(cmd->stats.read_hits);
 	disk_super->read_misses = cpu_to_le32(cmd->stats.read_misses);

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Lars-Peter Clausen <[email protected]>

commit 5a4e33c1c53ae7d4425f7d94e60e4458a37b349e upstream.

Fix the displayed phase for the ad9523 driver. Currently the most significant decimal place is dropped and all other digits are shifted one to the left. This is due to a multiplication by 10, which is not necessary, so remove it.

---
 drivers/iio/frequency/ad9523.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -641,7 +641,7 @@ static int ad9523_read_raw(struct iio_de
 		code = (AD9523_CLK_DIST_DIV_PHASE_REV(ret) * 3141592) /
 			AD9523_CLK_DIST_DIV_REV(ret);
 		*val = code / 1000000;
-		*val2 = (code % 1000000) * 10;
+		*val2 = code % 1000000;
 		return IIO_VAL_INT_PLUS_MICRO;
 	default:
 		return -EINVAL;

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Lars-Peter Clausen <[email protected]>

commit 9a5094ca29ea9b1da301b31fd377c0c0c4c23034 upstream.

A sysfs write callback function needs to either return the number of consumed characters or an error.

The ad952x_store() function currently returns 0 if the input value was "0", this will signal that no characters have been consumed and the function will be called repeatedly in a loop indefinitely. Fix this by returning number of supplied characters to indicate that the whole input string has been consumed.

---
 drivers/iio/frequency/ad9523.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -507,7 +507,7 @@ static ssize_t ad9523_store(struct devic
 		return ret;
 
 	if (!state)
-		return 0;
+		return len;
 
 	mutex_lock(&indio_dev->mlock);
 	switch ((u32)this_attr->address) {

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Steven Rostedt (VMware) <[email protected]>

commit f143641bfef9a4a60c57af30de26c63057e7e695 upstream.

Currently, when one echo's in 1 into tracing_on, the current tracer's "start()" function is executed, even if tracing_on was already one. This can lead to strange side effects. One being that if the hwlat tracer is enabled, and someone does "echo 1 > tracing_on" into tracing_on, the hwlat tracer's start() function is called again which will recreate another kernel thread, and make it unable to remove the old one.

---
 kernel/trace/trace.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

@@ -6209,7 +6209,9 @@ rb_simple_write(struct file *filp, const
 
 	if (buffer) {
 		mutex_lock(&trace_types_lock);
-		if (val) {
+		if (!!val == tracer_tracing_is_on(tr)) {
+			val = 0; /* do nothing */
+		} else if (val) {
 			tracer_tracing_on(tr);
 			if (tr->current_trace->start)
 				tr->current_trace->start(tr);

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Steven Rostedt (VMware) <[email protected]>

commit 757d9140072054528b13bbe291583d9823cde195 upstream.

Masami Hiramatsu reported:

Current trace-enable attribute in sysfs returns an error if user writes the same setting value as current one, e.g.

    # cat /sys/block/sda/trace/enable
    0
    # echo 0 > /sys/block/sda/trace/enable
    bash: echo: write error: Invalid argument
    # echo 1 > /sys/block/sda/trace/enable
    # echo 1 > /sys/block/sda/trace/enable
    bash: echo: write error: Device or resource busy

But this is not a preferred behavior, it should ignore if new setting is same as current one. This fixes the problem as below.

    # cat /sys/block/sda/trace/enable
    0
    # echo 0 > /sys/block/sda/trace/enable
    # echo 1 > /sys/block/sda/trace/enable
    # echo 1 > /sys/block/sda/trace/enable

---
 kernel/trace/blktrace.c |    4 ++++
 1 file changed, 4 insertions(+)

@@ -1734,6 +1734,10 @@ static ssize_t sysfs_blk_trace_attr_stor
 	mutex_lock(&bdev->bd_mutex);
 
 	if (attr == &dev_attr_enable) {
+		if (!!value == !!q->blk_trace) {
+			ret = 0;
+			goto out_unlock_bdev;
+		}
 		if (value)
 			ret = blk_trace_setup_queue(q, bdev);
 		else

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Snild Dolkow <[email protected]>

commit 3e536e222f2930534c252c1cc7ae799c725c5ff9 upstream.

There is a window for racing when printing directly to task->comm, allowing other threads to see a non-terminated string. The vsnprintf function fills the buffer, counts the truncated chars, then finally writes the \0 at the end.

creator other
vsnprintf:
fill (not terminated)
count the rest trace_sched_waking(p):
... memcpy(comm, p->comm, TASK_COMM_LEN)
write \0

The consequences depend on how 'other' uses the string. In our case, it was copied into the tracing system's saved cmdlines, a buffer of adjacent TASK_COMM_LEN-byte buffers (note the 'n' where 0 should be):

	crash-arm64> x/1024s savedcmd->saved_cmdlines | grep 'evenk'
	0xffffffd5b3818640:     "irq/497-pwr_evenkworker/u16:12"

...and a strcpy out of there would cause stack corruption:

	[224761.522292] Kernel panic - not syncing: stack-protector:
	    Kernel stack is corrupted in: ffffff9bf9783c78

	crash-arm64> kbt | grep 'comm\|trace_print_context'
	#6  0xffffff9bf9783c78 in trace_print_context+0x18c(+396)
	      comm (char [16]) =  "irq/497-pwr_even"

	crash-arm64> rd 0xffffffd4d0e17d14 8
	ffffffd4d0e17d14:  2f71726900000000 5f7277702d373934   ....irq/497-pwr_
	ffffffd4d0e17d24:  726f776b6e657665 3a3631752f72656b   evenkworker/u16:
	ffffffd4d0e17d34:  f9780248ff003231 cede60e0ffffff9b   12..H.x......`..
	ffffffd4d0e17d44:  cede60c8ffffffd4 00000fffffffffd4   .....`..........

The workaround in e09e28671 (use strlcpy in __trace_find_cmdline) was likely needed because of this same bug.

Solved by vsnprintf:ing to a local buffer, then using set_task_comm(). This way, there won't be a window where comm is not terminated.

---
 kernel/kthread.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

@@ -309,10 +309,16 @@ struct task_struct *kthread_create_on_no
 	task = create->result;
 	if (!IS_ERR(task)) {
 		static const struct sched_param param = { .sched_priority = 0 };
+		char name[TASK_COMM_LEN];
 		va_list args;
 
 		va_start(args, namefmt);
-		vsnprintf(task->comm, sizeof(task->comm), namefmt, args);
+		/*
+		 * task is already visible to other tasks, so updating
+		 * COMM must be protected.
+		 */
+		vsnprintf(name, sizeof(name), namefmt, args);
+		set_task_comm(task, name);
 		va_end(args);
 		/*
 		 * root may have changed our (kthreadd's) priority or CPU mask.

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Steven Rostedt (VMware) <[email protected]>

commit 016f8ffc48cb01d1e7701649c728c5d2e737d295 upstream.

While debugging another bug, I was looking at all the synchronize*() functions being used in kernel/trace, and noticed that trace_uprobes was using synchronize_sched(), with a comment to synchronize with {u,ret}_probe_trace_func(). When looking at those functions, the data is protected with "rcu_read_lock()" and not with "rcu_read_lock_sched()". This is using the wrong synchronize_*() function.

---
 kernel/trace/trace_uprobe.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -957,7 +957,7 @@ probe_event_disable(struct trace_uprobe
 
 		list_del_rcu(&link->list);
 		/* synchronize with u{,ret}probe_trace_func */
-		synchronize_sched();
+		synchronize_rcu();
 		kfree(link);
 
 		if (!list_empty(&tu->tp.files))

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Tomas Bortoli <[email protected]>

commit 10aa14527f458e9867cf3d2cc6b8cb0f6704448b upstream.

Added checks to prevent GPFs from raising.

---
 net/9p/trans_fd.c     |    5 ++++-
 net/9p/trans_rdma.c   |    3 +++
 net/9p/trans_virtio.c |    3 +++
 3 files changed, 10 insertions(+), 1 deletion(-)

@@ -934,7 +934,7 @@ p9_fd_create_tcp(struct p9_client *clien
 	if (err < 0)
 		return err;
 
-	if (valid_ipaddr4(addr) < 0)
+	if (addr == NULL || valid_ipaddr4(addr) < 0)
 		return -EINVAL;
 
 	csocket = NULL;

@@ -982,6 +982,9 @@ p9_fd_create_unix(struct p9_client *clie
 
 	csocket = NULL;
 
+	if (addr == NULL)
+		return -EINVAL;
+
 	if (strlen(addr) >= UNIX_PATH_MAX) {
 		pr_err("%s (%d): address too long: %s\n",
 		       __func__, task_pid_nr(current), addr);

@@ -623,6 +623,9 @@ rdma_create_trans(struct p9_client *clie
 	struct ib_qp_init_attr qp_attr;
 	struct ib_device_attr devattr;
 
+	if (addr == NULL)
+		return -EINVAL;
+
 	/* Parse the transport specific mount options */
 	err = parse_opts(args, &opts);
 	if (err < 0)

@@ -617,6 +617,9 @@ p9_virtio_create(struct p9_client *clien
 	int ret = -ENOENT;
 	int found = 0;
 
+	if (devname == NULL)
+		return -EINVAL;
+
 	mutex_lock(&virtio_9p_lock);
 	list_for_each_entry(chan, &virtio_chan_list, chan_list) {
 		if (!strncmp(devname, chan->tag, chan->tag_len) &&

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <[email protected]>

commit 0914bb965e38a055e9245637aed117efbe976e91 upstream.

"dev->nr_children" is the number of children which were parsed successfully in bl_parse_stripe(). It could be all of them and then, in that case, it is equal to v->stripe.volumes_count. Either way, the > should be >= so that we don't go beyond the end of what we're supposed to.

---
 fs/nfs/blocklayout/dev.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -157,7 +157,7 @@ static bool bl_map_stripe(struct pnfs_bl
 	chunk = div_u64(offset, dev->chunk_size);
 	div_u64_rem(chunk, dev->nr_children, &chunk_idx);
 
-	if (chunk_idx > dev->nr_children) {
+	if (chunk_idx >= dev->nr_children) {
 		dprintk("%s: invalid chunk idx %d (%lld/%lld)\n",
 			__func__, chunk_idx, offset, dev->chunk_size);
 		/* error, should not happen */

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Jon Hunter <[email protected]>

commit 6e1811900b6fe6f2b4665dba6bd6ed32c6b98575 upstream.

On all versions of Tegra30 Cardhu, the reset signal to the NXP PCA9546 I2C mux is connected to the Tegra GPIO BB0. Currently, this pin on the Tegra is not configured as a GPIO but as a special-function IO (SFIO) that is multiplexing the pin to an I2S controller. On exiting system suspend, I2C commands sent to the PCA9546 are failing because there is no ACK. Although it is not possible to see exactly what is happening to the reset during suspend, by ensuring it is configured as a GPIO and driven high, to de-assert the reset, the failures are no longer seen.

Please note that this GPIO is also used to drive the reset signal going to the camera connector on the board. However, given that there is no camera support currently for Cardhu, this should not have any impact.

---
 arch/arm/boot/dts/tegra30-cardhu.dtsi |    1 +
 1 file changed, 1 insertion(+)

@@ -200,6 +200,7 @@
 			#address-cells = <1>;
 			#size-cells = <0>;
 			reg = <0x70>;
+			reset-gpio = <&gpio TEGRA_GPIO(BB, 0) GPIO_ACTIVE_LOW>;
 		};
 	};
 

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Peter Zijlstra <[email protected]>

commit a6f572084fbee8b30f91465f4a085d7a90901c57 upstream.

Will noted that only checking mm_users is incorrect; we should also check mm_count in order to cover CPUs that have a lazy reference to this mm (and could do speculative TLB operations).

If removing this turns out to be a performance issue, we can re-instate a more complete check, but in tlb_table_flush() eliding the call_rcu_sched().

---
 mm/memory.c |    9 ---------
 1 file changed, 9 deletions(-)

@@ -359,15 +359,6 @@ void tlb_remove_table(struct mmu_gather
 {
 	struct mmu_table_batch **batch = &tlb->batch;
 
-	/*
-	 * When there's less then two users of this mm there cannot be a
-	 * concurrent page-table walk.
-	 */
-	if (atomic_read(&tlb->mm->mm_users) < 2) {
-		__tlb_remove_table(table);
-		return;
-	}
-
 	if (*batch == NULL) {
 		*batch = (struct mmu_table_batch *)__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
 		if (*batch == NULL) {

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Al Viro <[email protected]>

commit 9ba3eb5103cf56f0daaf07de4507df76e7813ed7 upstream.

---
 arch/alpha/kernel/osf_sys.c |   23 +++++++++--------------
 1 file changed, 9 insertions(+), 14 deletions(-)

@@ -560,25 +560,20 @@ SYSCALL_DEFINE0(getdtablesize)
  */
 SYSCALL_DEFINE2(osf_getdomainname, char __user *, name, int, namelen)
 {
-	unsigned len;
-	int i;
+	int len, err = 0;
+	char *kname;
 
-	if (!access_ok(VERIFY_WRITE, name, namelen))
-		return -EFAULT;
-
-	len = namelen;
-	if (len > 32)
-		len = 32;
+	if (namelen > 32)
+		namelen = 32;
 
 	down_read(&uts_sem);
-	for (i = 0; i < len; ++i) {
-		__put_user(utsname()->domainname[i], name + i);
-		if (utsname()->domainname[i] == '\0')
-			break;
-	}
+	kname = utsname()->domainname;
+	len = strnlen(kname, namelen);
+	if (copy_to_user(name, kname, min(len + 1, namelen)))
+		err = -EFAULT;
 	up_read(&uts_sem);
 
-	return 0;
+	return err;
 }
 
 /*

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Jann Horn <[email protected]>

commit 42a0cc3478584d4d63f68f2f5af021ddbea771fa upstream.

Holding uts_sem as a writer while accessing userspace memory allows a namespace admin to stall all processes that attempt to take uts_sem. Instead, move data through stack buffers and don't access userspace memory while uts_sem is held.

---
 arch/alpha/kernel/osf_sys.c      |   51 +++++++++-----------
 arch/sparc/kernel/sys_sparc_32.c |   22 +++++----
 arch/sparc/kernel/sys_sparc_64.c |   20 ++++----
 kernel/sys.c                     |   95 ++++++++++++++++++---------------------
 kernel/utsname_sysctl.c          |   41 ++++++++++------
 5 files changed, 119 insertions(+), 110 deletions(-)

@@ -525,24 +525,19 @@ SYSCALL_DEFINE4(osf_mount, unsigned long
 SYSCALL_DEFINE1(osf_utsname, char __user *, name)
 {
 	int error;
+	char tmp[5 * 32];
 
 	down_read(&uts_sem);
-	error = -EFAULT;
-	if (copy_to_user(name + 0, utsname()->sysname, 32))
-		goto out;
-	if (copy_to_user(name + 32, utsname()->nodename, 32))
-		goto out;
-	if (copy_to_user(name + 64, utsname()->release, 32))
-		goto out;
-	if (copy_to_user(name + 96, utsname()->version, 32))
-		goto out;
-	if (copy_to_user(name + 128, utsname()->machine, 32))
-		goto out;
+	memcpy(tmp + 0 * 32, utsname()->sysname, 32);
+	memcpy(tmp + 1 * 32, utsname()->nodename, 32);
+	memcpy(tmp + 2 * 32, utsname()->release, 32);
+	memcpy(tmp + 3 * 32, utsname()->version, 32);
+	memcpy(tmp + 4 * 32, utsname()->machine, 32);
+	up_read(&uts_sem);
 
-	error = 0;
- out:
-	up_read(&uts_sem);	
-	return error;
+	if (copy_to_user(name, tmp, sizeof(tmp)))
+		return -EFAULT;
+	return 0;
 }
 
 SYSCALL_DEFINE0(getpagesize)

@@ -562,18 +557,21 @@ SYSCALL_DEFINE2(osf_getdomainname, char
 {
 	int len, err = 0;
 	char *kname;
+	char tmp[32];
 
-	if (namelen > 32)
+	if (namelen < 0 || namelen > 32)
 		namelen = 32;
 
 	down_read(&uts_sem);
 	kname = utsname()->domainname;
 	len = strnlen(kname, namelen);
-	if (copy_to_user(name, kname, min(len + 1, namelen)))
-		err = -EFAULT;
+	len = min(len + 1, namelen);
+	memcpy(tmp, kname, len);
 	up_read(&uts_sem);
 
-	return err;
+	if (copy_to_user(name, tmp, len))
+		return -EFAULT;
+	return 0;
 }
 
 /*

@@ -735,13 +733,14 @@ SYSCALL_DEFINE3(osf_sysinfo, int, comman
 	};
 	unsigned long offset;
 	const char *res;
-	long len, err = -EINVAL;
+	long len;
+	char tmp[__NEW_UTS_LEN + 1];
 
 	offset = command-1;
 	if (offset >= ARRAY_SIZE(sysinfo_table)) {
 		/* Digital UNIX has a few unpublished interfaces here */
 		printk("sysinfo(%d)", command);
-		goto out;
+		return -EINVAL;
 	}
 
 	down_read(&uts_sem);

@@ -749,13 +748,11 @@ SYSCALL_DEFINE3(osf_sysinfo, int, comman
 	len = strlen(res)+1;
 	if ((unsigned long)len > (unsigned long)count)
 		len = count;
-	if (copy_to_user(buf, res, len))
-		err = -EFAULT;
-	else
-		err = 0;
+	memcpy(tmp, res, len);
 	up_read(&uts_sem);
- out:
-	return err;
+	if (copy_to_user(buf, tmp, len))
+		return -EFAULT;
+	return 0;
 }
 
 SYSCALL_DEFINE5(osf_getsysinfo, unsigned long, op, void __user *, buffer,

@@ -201,23 +201,27 @@ SYSCALL_DEFINE5(rt_sigaction, int, sig,
 
 asmlinkage long sys_getdomainname(char __user *name, int len)
 {
- 	int nlen, err;
- 	
+	int nlen, err;
+	char tmp[__NEW_UTS_LEN + 1];
+
 	if (len < 0)
 		return -EINVAL;
 
- 	down_read(&uts_sem);
- 	
+	down_read(&uts_sem);
+
 	nlen = strlen(utsname()->domainname) + 1;
 	err = -EINVAL;
 	if (nlen > len)
-		goto out;
+		goto out_unlock;
+	memcpy(tmp, utsname()->domainname, nlen);
+
+	up_read(&uts_sem);
 
-	err = -EFAULT;
-	if (!copy_to_user(name, utsname()->domainname, nlen))
-		err = 0;
+	if (copy_to_user(name, tmp, nlen))
+		return -EFAULT;
+	return 0;
 
-out:
+out_unlock:
 	up_read(&uts_sem);
 	return err;
 }

@@ -524,23 +524,27 @@ extern void check_pending(int signum);
 
 SYSCALL_DEFINE2(getdomainname, char __user *, name, int, len)
 {
-        int nlen, err;
+	int nlen, err;
+	char tmp[__NEW_UTS_LEN + 1];
 
 	if (len < 0)
 		return -EINVAL;
 
- 	down_read(&uts_sem);
- 	
+	down_read(&uts_sem);
+
 	nlen = strlen(utsname()->domainname) + 1;
 	err = -EINVAL;
 	if (nlen > len)
-		goto out;
+		goto out_unlock;
+	memcpy(tmp, utsname()->domainname, nlen);
+
+	up_read(&uts_sem);
 
-	err = -EFAULT;
-	if (!copy_to_user(name, utsname()->domainname, nlen))
-		err = 0;
+	if (copy_to_user(name, tmp, nlen))
+		return -EFAULT;
+	return 0;
 
-out:
+out_unlock:
 	up_read(&uts_sem);
 	return err;
 }

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Eric W. Biederman <[email protected]>

commit 36476beac4f8ca9dc7722790b2e8ef0e8e51034e upstream.

It is important that all maps are less than PAGE_SIZE or else setting the last byte of the buffer to '0' could write off the end of the allocated storage.

Correct the misleading comment.

---
 kernel/user_namespace.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -643,7 +643,7 @@ static ssize_t map_write(struct file *fi
 	if (!page)
 		goto out;
 
-	/* Only allow <= page size writes at the beginning of the file */
+	/* Only allow < page size writes at the beginning of the file */
 	ret = -EINVAL;
 	if ((*ppos != 0) || (count >= PAGE_SIZE))
 		goto out;

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Jann Horn <[email protected]>

commit 5820f140edef111a9ea2ef414ab2428b8cb805b1 upstream.

The old code would hold the userns_state_mutex indefinitely if memdup_user_nul stalled due to e.g. a userfault region. Prevent that by moving the memdup_user_nul in front of the mutex_lock().

Note: This changes the error precedence of invalid buf/count/*ppos vs map already written / capabilities missing.

---
 kernel/user_namespace.c |   22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

@@ -602,7 +602,16 @@ static ssize_t map_write(struct file *fi
 	struct uid_gid_extent *extent = NULL;
 	unsigned long page = 0;
 	char *kbuf, *pos, *next_line;
-	ssize_t ret = -EINVAL;
+	ssize_t ret;
+
+	/* Only allow < page size writes at the beginning of the file */
+	if ((*ppos != 0) || (count >= PAGE_SIZE))
+		return -EINVAL;
+
+	/* Slurp in the user data */
+	if (copy_from_user(kbuf, buf, count))
+		return -EFAULT;
+	kbuf[count] = '\0';
 
 	/*
 	 * The userns_state_mutex serializes all writes to any given map.

@@ -643,17 +652,6 @@ static ssize_t map_write(struct file *fi
 	if (!page)
 		goto out;
 
-	/* Only allow < page size writes at the beginning of the file */
-	ret = -EINVAL;
-	if ((*ppos != 0) || (count >= PAGE_SIZE))
-		goto out;
-
-	/* Slurp in the user data */
-	ret = -EFAULT;
-	if (copy_from_user(kbuf, buf, count))
-		goto out;
-	kbuf[count] = '\0';
-
 	/* Parse the user data */
 	ret = -EINVAL;
 	pos = kbuf;

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Richard Weinberger <[email protected]>

commit eef19816ada3abd56d9f20c88794cc2fea83ebb2 upstream.

Allocate the buffer after we return early.
Otherwise memory is being leaked.

---
 fs/ubifs/lprops.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

@@ -1091,10 +1091,6 @@ static int scan_check_cb(struct ubifs_in
 		}
 	}
 
-	buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
-	if (!buf)
-		return -ENOMEM;
-
 	/*
 	 * After an unclean unmount, empty and freeable LEBs
 	 * may contain garbage - do not scan them.

@@ -1113,6 +1109,10 @@ static int scan_check_cb(struct ubifs_in
 		return LPT_SCAN_CONTINUE;
 	}
 
+	buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
 	sleb = ubifs_scan(c, lnum, 0, buf, 0);
 	if (IS_ERR(sleb)) {
 		ret = PTR_ERR(sleb);

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Richard Weinberger <[email protected]>

commit 08acbdd6fd736b90f8d725da5a0de4de2dd6de62 upstream.

This reverts commit 353748a359f1821ee934afc579cf04572406b420. It bypassed the linux-mtd review process and fixes the issue not as it should.

---
 fs/ubifs/journal.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -1101,7 +1101,7 @@ static int recomp_data_node(struct ubifs
 	int err, len, compr_type, out_len;
 
 	out_len = le32_to_cpu(dn->size);
-	buf = kmalloc_array(out_len, WORST_COMPR_FACTOR, GFP_NOFS);
+	buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS);
 	if (!buf)
 		return -ENOMEM;
 

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Richard Weinberger <[email protected]>

commit 59965593205fa4044850d35ee3557cf0b7edcd14 upstream.

In ubifs_jnl_update() we sync parent and child inodes to the flash, in case of xattrs, the parent inode (AKA host inode) has a non-zero data_len. Therefore we need to adjust synced_i_size too.

This issue was reported by ubifs self tests unter a xattr related work
load.
UBIFS error (ubi0:0 pid 1896): dbg_check_synced_i_size: ui_size is 4, synced_i_size is 0, but inode is clean UBIFS error (ubi0:0 pid 1896): dbg_check_synced_i_size: i_ino 65, i_mode 0x81a4, i_size 4

---
 fs/ubifs/journal.c |    5 +++++
 1 file changed, 5 insertions(+)

@@ -656,6 +656,11 @@ int ubifs_jnl_update(struct ubifs_info *
 	spin_lock(&ui->ui_lock);
 	ui->synced_i_size = ui->ui_size;
 	spin_unlock(&ui->ui_lock);
+	if (xent) {
+		spin_lock(&host_ui->ui_lock);
+		host_ui->synced_i_size = host_ui->ui_size;
+		spin_unlock(&host_ui->ui_lock);
+	}
 	mark_inode_clean(c, ui);
 	mark_inode_clean(c, host_ui);
 	return 0;

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Vignesh R <[email protected]>

commit 38dabd91ff0bde33352ca3cc65ef515599b77a05 upstream.

pwm-tiehrpwm driver disables PWM output by putting it in low output state via active AQCSFRC register in ehrpwm_pwm_disable(). But, the AQCSFRC shadow register is not updated. Therefore, when shadow AQCSFRC register is re-enabled in ehrpwm_pwm_enable() (say to enable second PWM output), previous settings are lost as shadow register value is loaded into active register. This results in things like PWMA getting enabled automatically, when PWMB is enabled and vice versa. Fix this by updating AQCSFRC shadow register as well during ehrpwm_pwm_disable().

---
 drivers/pwm/pwm-tiehrpwm.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -384,6 +384,8 @@ static void ehrpwm_pwm_disable(struct pw
 		aqcsfrc_mask = AQCSFRC_CSFA_MASK;
 	}
 
+	/* Update shadow register first before modifying active register */
+	ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
 	/*
 	 * Changes to immediate action on Action Qualifier. This puts
 	 * Action Qualifier control on PWM output from next TBCLK

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mikulas Patocka <[email protected]>

commit 8c5b044299951acd91e830a688dd920477ea1eda upstream.

I have a USB display adapter using the udlfb driver and I use it on an ARM board that doesn't have any graphics card. When I plug the adapter in, the console is properly displayed, however when I unplug and re-plug the adapter, the console is not displayed and I can't access it until I reboot the board.

The reason is this:
When the adapter is unplugged, dlfb_usb_disconnect calls unlink_framebuffer, then it waits until the reference count drops to zero and then it deallocates the framebuffer. However, the console that is attached to the framebuffer device keeps the reference count non-zero, so the framebuffer device is never destroyed. When the USB adapter is plugged again, it creates a new device /dev/fb1 and the console is not attached to it.

This patch fixes the bug by unbinding the console from unlink_framebuffer. The code to unbind the console is moved from do_unregister_framebuffer to a function unbind_console. When the console is unbound, the reference count drops to zero and the udlfb driver frees the framebuffer. When the adapter is plugged back, a new framebuffer is created and the console is attached to it.

---
 drivers/video/fbdev/core/fbmem.c |   38 ++++++++++++++++++++++++++++++++------
 1 file changed, 32 insertions(+), 6 deletions(-)

@@ -1687,12 +1687,12 @@ static int do_register_framebuffer(struc
 	return 0;
 }
 
-static int do_unregister_framebuffer(struct fb_info *fb_info)
+static int unbind_console(struct fb_info *fb_info)
 {
 	struct fb_event event;
-	int i, ret = 0;
+	int ret;
+	int i = fb_info->node;
 
-	i = fb_info->node;
 	if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info)
 		return -EINVAL;
 

@@ -1707,17 +1707,29 @@ static int do_unregister_framebuffer(str
 	unlock_fb_info(fb_info);
 	console_unlock();
 
+	return ret;
+}
+
+static int __unlink_framebuffer(struct fb_info *fb_info);
+
+static int do_unregister_framebuffer(struct fb_info *fb_info)
+{
+	struct fb_event event;
+	int ret;
+
+	ret = unbind_console(fb_info);
+
 	if (ret)
 		return -EINVAL;
 
 	pm_vt_switch_unregister(fb_info->dev);
 
-	unlink_framebuffer(fb_info);
+	__unlink_framebuffer(fb_info);
 	if (fb_info->pixmap.addr &&
 	    (fb_info->pixmap.flags & FB_PIXMAP_DEFAULT))
 		kfree(fb_info->pixmap.addr);
 	fb_destroy_modelist(&fb_info->modelist);
-	registered_fb[i] = NULL;
+	registered_fb[fb_info->node] = NULL;
 	num_registered_fb--;
 	fb_cleanup_device(fb_info);
 	event.info = fb_info;

@@ -1730,7 +1742,7 @@ static int do_unregister_framebuffer(str
 	return 0;
 }
 
-int unlink_framebuffer(struct fb_info *fb_info)
+static int __unlink_framebuffer(struct fb_info *fb_info)
 {
 	int i;
 

@@ -1742,6 +1754,20 @@ int unlink_framebuffer(struct fb_info *f
 		device_destroy(fb_class, MKDEV(FB_MAJOR, i));
 		fb_info->dev = NULL;
 	}
+
+	return 0;
+}
+
+int unlink_framebuffer(struct fb_info *fb_info)
+{
+	int ret;
+
+	ret = __unlink_framebuffer(fb_info);
+	if (ret)
+		return ret;
+
+	unbind_console(fb_info);
+
 	return 0;
 }
 EXPORT_SYMBOL(unlink_framebuffer);

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Mikulas Patocka <[email protected]>

commit bb24153a3f13dd0dbc1f8055ad97fe346d598f66 upstream.

The default delay 5 jiffies is too much when the kernel is compiled with HZ=100 - it results in jumpy cursor in Xwindow.

In order to find out the optimal delay, I benchmarked the driver on 1280x720x30fps video. I found out that with HZ=1000, 10ms is acceptable, but with HZ=250 or HZ=300, we need 4ms, so that the video is played without any frame skips.

This patch changes the delay to this value.

---
 include/video/udlfb.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -87,7 +87,7 @@ struct dlfb_data {
 #define MIN_RAW_PIX_BYTES	2
 #define MIN_RAW_CMD_BYTES	(RAW_HEADER_BYTES + MIN_RAW_PIX_BYTES)
 
-#define DL_DEFIO_WRITE_DELAY    5 /* fb_deferred_io.delay in jiffies */
+#define DL_DEFIO_WRITE_DELAY    msecs_to_jiffies(HZ <= 300 ? 4 : 10) /* optimal value for 720p video */
 #define DL_DEFIO_WRITE_DISABLE  (HZ*60) /* "disable" with long delay */
 
 /* remove these once align.h patch is taken into kernel */

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Christian Brauner <[email protected]>

commit 82c9a927bc5df6e06b72d206d24a9d10cced4eb5 upstream.

When running in a container with a user namespace, if you call getxattr with name = "system.posix_acl_access" and size % 8 != 4, then getxattr silently skips the user namespace fixup that it normally does resulting in un-fixed-up data being returned.
This is caused by posix_acl_fix_xattr_to_user() being passed the total buffer size and not the actual size of the xattr as returned by vfs_getxattr().
This commit passes the actual length of the xattr as returned by vfs_getxattr() down.

A reproducer for the issue is:

touch acl_posix

setfacl -m user:0:rwx acl_posix

and the compile:

  #define _GNU_SOURCE
  #include <errno.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <sys/types.h>
  #include <unistd.h>
  #include <attr/xattr.h>

  /* Run in user namespace with nsuid 0 mapped to uid != 0 on the host. */
  int main(int argc, void **argv)
  {
          ssize_t ret1, ret2;
          char buf1[128], buf2[132];
          int fret = EXIT_SUCCESS;
          char *file;

          if (argc < 2) {
                  fprintf(stderr,
                          "Please specify a file with "
                          "\"system.posix_acl_access\" permissions set\n");
                  _exit(EXIT_FAILURE);
          }
          file = argv[1];

          ret1 = getxattr(file, "system.posix_acl_access",
                          buf1, sizeof(buf1));
          if (ret1 < 0) {
                  fprintf(stderr, "%s - Failed to retrieve "
                                  "\"system.posix_acl_access\" "
                                  "from \"%s\"\n", strerror(errno), file);
                  _exit(EXIT_FAILURE);
          }

          ret2 = getxattr(file, "system.posix_acl_access",
                          buf2, sizeof(buf2));
          if (ret2 < 0) {
                  fprintf(stderr, "%s - Failed to retrieve "
                                  "\"system.posix_acl_access\" "
                                  "from \"%s\"\n", strerror(errno), file);
                  _exit(EXIT_FAILURE);
          }

          if (ret1 != ret2) {
                  fprintf(stderr, "The value of \"system.posix_acl_"
                                  "access\" for file \"%s\" changed "
                                  "between two successive calls\n", file);
                  _exit(EXIT_FAILURE);
          }

          for (ssize_t i = 0; i < ret2; i++) {
                  if (buf1[i] == buf2[i])
                          continue;

                  fprintf(stderr,
                          "Unexpected different in byte %zd: "
                          "%02x != %02x\n", i, buf1[i], buf2[i]);
                  fret = EXIT_FAILURE;
          }

          if (fret == EXIT_SUCCESS)
                  fprintf(stderr, "Test passed\n");
          else
                  fprintf(stderr, "Test failed\n");

          _exit(fret);

}
and run:

./tester acl_posix

On a non-fixed up kernel this should return something like:

  root@c1:/# ./t
  Unexpected different in byte 16: ffffffa0 != 00
  Unexpected different in byte 17: ffffff86 != 00
  Unexpected different in byte 18: 01 != 00

and on a fixed kernel:

  root@c1:~# ./t
  Test passed

---
 fs/xattr.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -455,7 +455,7 @@ getxattr(struct dentry *d, const char __
 	if (error > 0) {
 		if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
 		    (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
-			posix_acl_fix_xattr_to_user(kvalue, size);
+			posix_acl_fix_xattr_to_user(kvalue, error);
 		if (size && copy_to_user(value, kvalue, error))
 			error = -EFAULT;
 	} else if (error == -ERANGE && size >= XATTR_SIZE_MAX) {

3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Shan Hai <[email protected]>

commit 3943b040f11ed0cc6d4585fd286a623ca8634547 upstream.

The writeback thread would exit with a lock held when the cache device is detached via sysfs interface, fix it by releasing the held lock before exiting the while-loop.

---
 drivers/md/bcache/writeback.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

@@ -462,8 +462,10 @@ static int bch_writeback_thread(void *ar
 			 * data on cache. BCACHE_DEV_DETACHING flag is set in
 			 * bch_cached_dev_detach().
 			 */
-			if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags))
+			if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags)) {
+				up_write(&dc->writeback_lock);
 				break;
+			}
 		}
 
 		up_write(&dc->writeback_lock);

Merged, compiled with -Werror, and installed onto my Pixel XL.

No initial issues noticed in dmesg or general usage.

Thanks!
Nathan

Cleanly merges and builds with Werror in my oneplus3 tree. No immediate regressions noticed. Thanks for the update. --
Harsh Shandilya, PRJKT Development LLC

Thanks for testing and letting me know.

greg k-h

Affects at least 3.18, 4.4, 4.9:

Building powerpc:allmodconfig ... failed
--------------
Error log:
arch/powerpc/kernel/fadump.c: In function 'free_crash_memory_ranges':
arch/powerpc/kernel/fadump.c:733:2: error: implicit declaration of function 'kfree'

arch/powerpc/kernel/fadump.c: In function 'allocate_crash_memory_ranges':
arch/powerpc/kernel/fadump.c:752:2: error: implicit declaration of function 'krealloc'

Affects at least 4.9 (on top of the above):

Building powerpc:defconfig ... failed
Building powerpc:allmodconfig ... failed
--------------
arch/powerpc/platforms/powernv/pci-ioda.c: In function 'pnv_pci_enable_bridge':
arch/powerpc/platforms/powernv/pci-ioda.c:3145:4: error: implicit declaration of function 'pci_err'

4.14, 4,18 unknown.

Very preliminary; the builds will take a while to complete. My builders are struggling with stability problems when running 4.18.6 kernels.

Guenter

Build results:

	total: 139 pass: 138 fail: 1
Failed builds:
	powerpc:allmodconfig
Qemu test results:
	total: 217 pass: 217 fail: 0

Details are available at https://kerneltests.org/builders/.

Guenter

Pushed out a -rc2 with this fixed up.

thanks,

greg k-h

For v3.18.121-30-g60d7419e2ba3:

Build results:

	total: 139 pass: 139 fail: 0
Qemu test results:
	total: 217 pass: 217 fail: 0

Guenter

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

thanks,
-- Shuah