Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull misc vfs updates from Al Viro:
 "All kinds of stuff.  That probably should've been 5 or 6 separate
  branches, but by the time I'd realized how large and mixed that bag
  had become it had been too close to -final to play with rebasing.

  Some fs/namei.c cleanups there, memdup_user_nul() introduction and
  switching open-coded instances, burying long-dead code, whack-a-mole
  of various kinds, several new helpers for ->llseek(), assorted
  cleanups and fixes from various people, etc.

  One piece probably deserves special mention - Neil's
  lookup_one_len_unlocked().  Similar to lookup_one_len(), but gets
  called without ->i_mutex and tries to avoid ever taking it.  That, of
  course, means that it's not useful for any directory modifications,
  but things like getting inode attributes in nfds readdirplus are fine
  with that.  I really should've asked for moratorium on lookup-related
  changes this cycle, but since I hadn't done that early enough...  I
  *am* asking for that for the coming cycle, though - I'm going to try
  and get conversion of i_mutex to rwsem with ->lookup() done under lock
  taken shared.

  There will be a patch closer to the end of the window, along the lines
  of the one Linus had posted last May - mechanical conversion of
  ->i_mutex accesses to inode_lock()/inode_unlock()/inode_trylock()/
  inode_is_locked()/inode_lock_nested().  To quote Linus back then:

    -----
    |    This is an automated patch using
    |
    |        sed 's/mutex_lock(&\(.*\)->i_mutex)/inode_lock(\1)/'
    |        sed 's/mutex_unlock(&\(.*\)->i_mutex)/inode_unlock(\1)/'
    |        sed 's/mutex_lock_nested(&\(.*\)->i_mutex,[     ]*I_MUTEX_\([A-Z0-9_]*\))/inode_lock_nested(\1, I_MUTEX_\2)/'
    |        sed 's/mutex_is_locked(&\(.*\)->i_mutex)/inode_is_locked(\1)/'
    |        sed 's/mutex_trylock(&\(.*\)->i_mutex)/inode_trylock(\1)/'
    |
    |    with a very few manual fixups
    -----

  I'm going to send that once the ->i_mutex-affecting stuff in -next
  gets mostly merged (or when Linus says he's about to stop taking
  merges)"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  nfsd: don't hold i_mutex over userspace upcalls
  fs:affs:Replace time_t with time64_t
  fs/9p: use fscache mutex rather than spinlock
  proc: add a reschedule point in proc_readfd_common()
  logfs: constify logfs_block_ops structures
  fcntl: allow to set O_DIRECT flag on pipe
  fs: __generic_file_splice_read retry lookup on AOP_TRUNCATED_PAGE
  fs: xattr: Use kvfree()
  [s390] page_to_phys() always returns a multiple of PAGE_SIZE
  nbd: use ->compat_ioctl()
  fs: use block_device name vsprintf helper
  lib/vsprintf: add %*pg format specifier
  fs: use gendisk->disk_name where possible
  poll: plug an unused argument to do_poll
  amdkfd: don't open-code memdup_user()
  cdrom: don't open-code memdup_user()
  rsxx: don't open-code memdup_user()
  mtip32xx: don't open-code memdup_user()
  [um] mconsole: don't open-code memdup_user_nul()
  [um] hostaudio: don't open-code memdup_user()
  ...

4 files changed, 93 insertions, 199 deletions

diff --git a/drivers/net/wireless/ath/wil6210/debugfs.c b/drivers/net/wireless/ath/wil6210/debugfs.c
index 97bc186f9728..a1d10b85989f 100644
--- a/drivers/net/wireless/ath/wil6210/debugfs.c
+++ b/drivers/net/wireless/ath/wil6210/debugfs.c
@@ -580,16 +580,10 @@ static ssize_t wil_write_file_rxon(struct file *file, const char __user *buf,
 	long channel;
 	bool on;
 
-	char *kbuf = kmalloc(len + 1, GFP_KERNEL);
-
-	if (!kbuf)
-		return -ENOMEM;
-	if (copy_from_user(kbuf, buf, len)) {
-		kfree(kbuf);
-		return -EIO;
-	}
+	char *kbuf = memdup_user_nul(buf, len);
 
-	kbuf[len] = '\0';
+	if (IS_ERR(kbuf))
+		return PTR_ERR(kbuf);
 	rc = kstrtol(kbuf, 0, &channel);
 	kfree(kbuf);
 	if (rc)
diff --git a/drivers/net/wireless/libertas/debugfs.c b/drivers/net/wireless/libertas/debugfs.c
index 26cbf1dcc662..faed1823c58e 100644
--- a/drivers/net/wireless/libertas/debugfs.c
+++ b/drivers/net/wireless/libertas/debugfs.c
@@ -56,19 +56,15 @@ static ssize_t lbs_sleepparams_write(struct file *file,
 				loff_t *ppos)
 {
 	struct lbs_private *priv = file->private_data;
-	ssize_t buf_size, ret;
+	ssize_t ret;
 	struct sleep_params sp;
 	int p1, p2, p3, p4, p5, p6;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *)addr;
-	if (!buf)
-		return -ENOMEM;
+	char *buf;
+
+	buf = memdup_user_nul(user_buf, min(count, len - 1));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
-	buf_size = min(count, len - 1);
-	if (copy_from_user(buf, user_buf, buf_size)) {
-		ret = -EFAULT;
-		goto out_unlock;
-	}
 	ret = sscanf(buf, "%d %d %d %d %d %d", &p1, &p2, &p3, &p4, &p5, &p6);
 	if (ret != 6) {
 		ret = -EINVAL;
@@ -88,7 +84,7 @@ static ssize_t lbs_sleepparams_write(struct file *file,
 		ret = -EINVAL;
 
 out_unlock:
-	free_page(addr);
+	kfree(buf);
 	return ret;
 }
 
@@ -125,18 +121,14 @@ static ssize_t lbs_host_sleep_write(struct file *file,
 				loff_t *ppos)
 {
 	struct lbs_private *priv = file->private_data;
-	ssize_t buf_size, ret;
+	ssize_t ret;
 	int host_sleep;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *)addr;
-	if (!buf)
-		return -ENOMEM;
+	char *buf;
+
+	buf = memdup_user_nul(user_buf, min(count, len - 1));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
-	buf_size = min(count, len - 1);
-	if (copy_from_user(buf, user_buf, buf_size)) {
-		ret = -EFAULT;
-		goto out_unlock;
-	}
 	ret = sscanf(buf, "%d", &host_sleep);
 	if (ret != 1) {
 		ret = -EINVAL;
@@ -162,7 +154,7 @@ static ssize_t lbs_host_sleep_write(struct file *file,
 		ret = count;
 
 out_unlock:
-	free_page(addr);
+	kfree(buf);
 	return ret;
 }
 
@@ -281,21 +273,15 @@ static ssize_t lbs_threshold_write(uint16_t tlv_type, uint16_t event_mask,
 	struct cmd_ds_802_11_subscribe_event *events;
 	struct mrvl_ie_thresholds *tlv;
 	struct lbs_private *priv = file->private_data;
-	ssize_t buf_size;
 	int value, freq, new_mask;
 	uint16_t curr_mask;
 	char *buf;
 	int ret;
 
-	buf = (char *)get_zeroed_page(GFP_KERNEL);
-	if (!buf)
-		return -ENOMEM;
+	buf = memdup_user_nul(userbuf, min(count, len - 1));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
-	buf_size = min(count, len - 1);
-	if (copy_from_user(buf, userbuf, buf_size)) {
-		ret = -EFAULT;
-		goto out_page;
-	}
 	ret = sscanf(buf, "%d %d %d", &value, &freq, &new_mask);
 	if (ret != 3) {
 		ret = -EINVAL;
@@ -343,7 +329,7 @@ static ssize_t lbs_threshold_write(uint16_t tlv_type, uint16_t event_mask,
  out_events:
 	kfree(events);
  out_page:
-	free_page((unsigned long)buf);
+	kfree(buf);
 	return ret;
 }
 
@@ -472,22 +458,15 @@ static ssize_t lbs_rdmac_write(struct file *file,
 				    size_t count, loff_t *ppos)
 {
 	struct lbs_private *priv = file->private_data;
-	ssize_t res, buf_size;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *)addr;
-	if (!buf)
-		return -ENOMEM;
+	char *buf;
+
+	buf = memdup_user_nul(userbuf, min(count, len - 1));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
-	buf_size = min(count, len - 1);
-	if (copy_from_user(buf, userbuf, buf_size)) {
-		res = -EFAULT;
-		goto out_unlock;
-	}
 	priv->mac_offset = simple_strtoul(buf, NULL, 16);
-	res = count;
-out_unlock:
-	free_page(addr);
-	return res;
+	kfree(buf);
+	return count;
 }
 
 static ssize_t lbs_wrmac_write(struct file *file,
@@ -496,18 +475,14 @@ static ssize_t lbs_wrmac_write(struct file *file,
 {
 
 	struct lbs_private *priv = file->private_data;
-	ssize_t res, buf_size;
+	ssize_t res;
 	u32 offset, value;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *)addr;
-	if (!buf)
-		return -ENOMEM;
+	char *buf;
+
+	buf = memdup_user_nul(userbuf, min(count, len - 1));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
-	buf_size = min(count, len - 1);
-	if (copy_from_user(buf, userbuf, buf_size)) {
-		res = -EFAULT;
-		goto out_unlock;
-	}
 	res = sscanf(buf, "%x %x", &offset, &value);
 	if (res != 2) {
 		res = -EFAULT;
@@ -520,7 +495,7 @@ static ssize_t lbs_wrmac_write(struct file *file,
 	if (!res)
 		res = count;
 out_unlock:
-	free_page(addr);
+	kfree(buf);
 	return res;
 }
 
@@ -554,22 +529,16 @@ static ssize_t lbs_rdbbp_write(struct file *file,
 				    size_t count, loff_t *ppos)
 {
 	struct lbs_private *priv = file->private_data;
-	ssize_t res, buf_size;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *)addr;
-	if (!buf)
-		return -ENOMEM;
+	char *buf;
+
+	buf = memdup_user_nul(userbuf, min(count, len - 1));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
-	buf_size = min(count, len - 1);
-	if (copy_from_user(buf, userbuf, buf_size)) {
-		res = -EFAULT;
-		goto out_unlock;
-	}
 	priv->bbp_offset = simple_strtoul(buf, NULL, 16);
-	res = count;
-out_unlock:
-	free_page(addr);
-	return res;
+	kfree(buf);
+
+	return count;
 }
 
 static ssize_t lbs_wrbbp_write(struct file *file,
@@ -578,18 +547,14 @@ static ssize_t lbs_wrbbp_write(struct file *file,
 {
 
 	struct lbs_private *priv = file->private_data;
-	ssize_t res, buf_size;
+	ssize_t res;
 	u32 offset, value;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *)addr;
-	if (!buf)
-		return -ENOMEM;
+	char *buf;
+
+	buf = memdup_user_nul(userbuf, min(count, len - 1));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
-	buf_size = min(count, len - 1);
-	if (copy_from_user(buf, userbuf, buf_size)) {
-		res = -EFAULT;
-		goto out_unlock;
-	}
 	res = sscanf(buf, "%x %x", &offset, &value);
 	if (res != 2) {
 		res = -EFAULT;
@@ -602,7 +567,7 @@ static ssize_t lbs_wrbbp_write(struct file *file,
 	if (!res)
 		res = count;
 out_unlock:
-	free_page(addr);
+	kfree(buf);
 	return res;
 }
 
@@ -636,22 +601,15 @@ static ssize_t lbs_rdrf_write(struct file *file,
 				    size_t count, loff_t *ppos)
 {
 	struct lbs_private *priv = file->private_data;
-	ssize_t res, buf_size;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *)addr;
-	if (!buf)
-		return -ENOMEM;
+	char *buf;
+
+	buf = memdup_user_nul(userbuf, min(count, len - 1));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
-	buf_size = min(count, len - 1);
-	if (copy_from_user(buf, userbuf, buf_size)) {
-		res = -EFAULT;
-		goto out_unlock;
-	}
 	priv->rf_offset = simple_strtoul(buf, NULL, 16);
-	res = count;
-out_unlock:
-	free_page(addr);
-	return res;
+	kfree(buf);
+	return count;
 }
 
 static ssize_t lbs_wrrf_write(struct file *file,
@@ -660,18 +618,14 @@ static ssize_t lbs_wrrf_write(struct file *file,
 {
 
 	struct lbs_private *priv = file->private_data;
-	ssize_t res, buf_size;
+	ssize_t res;
 	u32 offset, value;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *)addr;
-	if (!buf)
-		return -ENOMEM;
+	char *buf;
+
+	buf = memdup_user_nul(userbuf, min(count, len - 1));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
-	buf_size = min(count, len - 1);
-	if (copy_from_user(buf, userbuf, buf_size)) {
-		res = -EFAULT;
-		goto out_unlock;
-	}
 	res = sscanf(buf, "%x %x", &offset, &value);
 	if (res != 2) {
 		res = -EFAULT;
@@ -684,7 +638,7 @@ static ssize_t lbs_wrrf_write(struct file *file,
 	if (!res)
 		res = count;
 out_unlock:
-	free_page(addr);
+	kfree(buf);
 	return res;
 }
 
@@ -915,16 +869,9 @@ static ssize_t lbs_debugfs_write(struct file *f, const char __user *buf,
 	if (cnt == 0)
 		return 0;
 
-	pdata = kmalloc(cnt + 1, GFP_KERNEL);
-	if (pdata == NULL)
-		return 0;
-
-	if (copy_from_user(pdata, buf, cnt)) {
-		lbs_deb_debugfs("Copy from user failed\n");
-		kfree(pdata);
-		return 0;
-	}
-	pdata[cnt] = '\0';
+	pdata = memdup_user_nul(buf, cnt);
+	if (IS_ERR(pdata))
+		return PTR_ERR(pdata);
 
 	p0 = pdata;
 	for (i = 0; i < num_of_items; i++) {
diff --git a/drivers/net/wireless/mwifiex/debugfs.c b/drivers/net/wireless/mwifiex/debugfs.c
index 9824d8dd2b44..241e1c3fbf08 100644
--- a/drivers/net/wireless/mwifiex/debugfs.c
+++ b/drivers/net/wireless/mwifiex/debugfs.c
@@ -447,20 +447,13 @@ static ssize_t
 mwifiex_regrdwr_write(struct file *file,
 		      const char __user *ubuf, size_t count, loff_t *ppos)
 {
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *) addr;
-	size_t buf_size = min_t(size_t, count, PAGE_SIZE - 1);
+	char *buf;
 	int ret;
 	u32 reg_type = 0, reg_offset = 0, reg_value = UINT_MAX;
 
-	if (!buf)
-		return -ENOMEM;
-
-
-	if (copy_from_user(buf, ubuf, buf_size)) {
-		ret = -EFAULT;
-		goto done;
-	}
+	buf = memdup_user_nul(ubuf, min(count, (size_t)(PAGE_SIZE - 1)));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
 	sscanf(buf, "%u %x %x", &reg_type, &reg_offset, &reg_value);
 
@@ -474,7 +467,7 @@ mwifiex_regrdwr_write(struct file *file,
 		ret = count;
 	}
 done:
-	free_page(addr);
+	kfree(buf);
 	return ret;
 }
 
@@ -572,17 +565,11 @@ mwifiex_debug_mask_write(struct file *file, const char __user *ubuf,
 	int ret;
 	unsigned long debug_mask;
 	struct mwifiex_private *priv = (void *)file->private_data;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (void *)addr;
-	size_t buf_size = min(count, (size_t)(PAGE_SIZE - 1));
+	char *buf;
 
-	if (!buf)
-		return -ENOMEM;
-
-	if (copy_from_user(buf, ubuf, buf_size)) {
-		ret = -EFAULT;
-		goto done;
-	}
+	buf = memdup_user_nul(ubuf, min(count, (size_t)(PAGE_SIZE - 1)));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
 	if (kstrtoul(buf, 0, &debug_mask)) {
 		ret = -EINVAL;
@@ -592,7 +579,7 @@ mwifiex_debug_mask_write(struct file *file, const char __user *ubuf,
 	priv->adapter->debug_mask = debug_mask;
 	ret = count;
 done:
-	free_page(addr);
+	kfree(buf);
 	return ret;
 }
 
@@ -609,17 +596,11 @@ mwifiex_memrw_write(struct file *file, const char __user *ubuf, size_t count,
 	struct mwifiex_ds_mem_rw mem_rw;
 	u16 cmd_action;
 	struct mwifiex_private *priv = (void *)file->private_data;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (void *)addr;
-	size_t buf_size = min(count, (size_t)(PAGE_SIZE - 1));
-
-	if (!buf)
-		return -ENOMEM;
+	char *buf;
 
-	if (copy_from_user(buf, ubuf, buf_size)) {
-		ret = -EFAULT;
-		goto done;
-	}
+	buf = memdup_user_nul(ubuf, min(count, (size_t)(PAGE_SIZE - 1)));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
 	ret = sscanf(buf, "%c %x %x", &cmd, &mem_rw.addr, &mem_rw.value);
 	if (ret != 3) {
@@ -645,7 +626,7 @@ mwifiex_memrw_write(struct file *file, const char __user *ubuf, size_t count,
 		ret = count;
 
 done:
-	free_page(addr);
+	kfree(buf);
 	return ret;
 }
 
@@ -686,20 +667,13 @@ static ssize_t
 mwifiex_rdeeprom_write(struct file *file,
 		       const char __user *ubuf, size_t count, loff_t *ppos)
 {
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *) addr;
-	size_t buf_size = min_t(size_t, count, PAGE_SIZE - 1);
+	char *buf;
 	int ret = 0;
 	int offset = -1, bytes = -1;
 
-	if (!buf)
-		return -ENOMEM;
-
-
-	if (copy_from_user(buf, ubuf, buf_size)) {
-		ret = -EFAULT;
-		goto done;
-	}
+	buf = memdup_user_nul(ubuf, min(count, (size_t)(PAGE_SIZE - 1)));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
 	sscanf(buf, "%d %d", &offset, &bytes);
 
@@ -712,7 +686,7 @@ mwifiex_rdeeprom_write(struct file *file,
 		ret = count;
 	}
 done:
-	free_page(addr);
+	kfree(buf);
 	return ret;
 }
 
@@ -771,21 +745,15 @@ mwifiex_hscfg_write(struct file *file, const char __user *ubuf,
 		    size_t count, loff_t *ppos)
 {
 	struct mwifiex_private *priv = (void *)file->private_data;
-	unsigned long addr = get_zeroed_page(GFP_KERNEL);
-	char *buf = (char *)addr;
-	size_t buf_size = min_t(size_t, count, PAGE_SIZE - 1);
+	char *buf;
 	int ret, arg_num;
 	struct mwifiex_ds_hs_cfg hscfg;
 	int conditions = HS_CFG_COND_DEF;
 	u32 gpio = HS_CFG_GPIO_DEF, gap = HS_CFG_GAP_DEF;
 
-	if (!buf)
-		return -ENOMEM;
-
-	if (copy_from_user(buf, ubuf, buf_size)) {
-		ret = -EFAULT;
-		goto done;
-	}
+	buf = memdup_user_nul(ubuf, min(count, (size_t)(PAGE_SIZE - 1)));
+	if (IS_ERR(buf))
+		return PTR_ERR(buf);
 
 	arg_num = sscanf(buf, "%d %x %x", &conditions, &gpio, &gap);
 
@@ -823,7 +791,7 @@ mwifiex_hscfg_write(struct file *file, const char __user *ubuf,
 	priv->adapter->hs_enabling = false;
 	ret = count;
 done:
-	free_page(addr);
+	kfree(buf);
 	return ret;
 }
 
diff --git a/drivers/net/wireless/ti/wlcore/debugfs.c b/drivers/net/wireless/ti/wlcore/debugfs.c
index eb43f94a1597..be72306f8c69 100644
--- a/drivers/net/wireless/ti/wlcore/debugfs.c
+++ b/drivers/net/wireless/ti/wlcore/debugfs.c
@@ -1205,26 +1205,11 @@ err_out:
 
 static loff_t dev_mem_seek(struct file *file, loff_t offset, int orig)
 {
-	loff_t ret;
-
 	/* only requests of dword-aligned size and offset are supported */
 	if (offset % 4)
 		return -EINVAL;
 
-	switch (orig) {
-	case SEEK_SET:
-		file->f_pos = offset;
-		ret = file->f_pos;
-		break;
-	case SEEK_CUR:
-		file->f_pos += offset;
-		ret = file->f_pos;
-		break;
-	default:
-		ret = -EINVAL;
-	}
-
-	return ret;
+	return no_seek_end_llseek(file, offset, orig);
 }
 
 static const struct file_operations dev_mem_ops = {