Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "11 fixes"

* emailed patches form Andrew Morton <akpm@linux-foundation.org>:
  reiserfs: fix buffer overflow with long warning messages
  checkpatch: fix duplicate invalid vsprintf pointer extension '%p<foo>' messages
  mm: do not bug_on on incorrect length in __mm_populate()
  mm/memblock.c: do not complain about top-down allocations for !MEMORY_HOTREMOVE
  fs, elf: make sure to page align bss in load_elf_library
  x86/purgatory: add missing FORCE to Makefile target
  net/9p/client.c: put refcount of trans_mod in error case in parse_opts()
  mm: allow arch to supply p??_free_tlb functions
  autofs: fix slab out of bounds read in getname_kernel()
  fs/proc/task_mmu.c: fix Locked field in /proc/pid/smaps*
  mm: do not drop unused pages when userfaultd is running

12 files changed, 133 insertions, 99 deletions

diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile
index 2e9ee023e6bc..81a8e33115ad 100644
--- a/arch/x86/purgatory/Makefile
+++ b/arch/x86/purgatory/Makefile
@@ -6,7 +6,7 @@ purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string
 targets += $(purgatory-y)
 PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
 
-$(obj)/sha256.o: $(srctree)/lib/sha256.c
+$(obj)/sha256.o: $(srctree)/lib/sha256.c FORCE
 	$(call if_changed_rule,cc_o_c)
 
 LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib -z nodefaultlib
diff --git a/fs/autofs/dev-ioctl.c b/fs/autofs/dev-ioctl.c
index ea4ca1445ab7..86eafda4a652 100644
--- a/fs/autofs/dev-ioctl.c
+++ b/fs/autofs/dev-ioctl.c
@@ -135,6 +135,15 @@ static int validate_dev_ioctl(int cmd, struct autofs_dev_ioctl *param)
 				cmd);
 			goto out;
 		}
+	} else {
+		unsigned int inr = _IOC_NR(cmd);
+
+		if (inr == AUTOFS_DEV_IOCTL_OPENMOUNT_CMD ||
+		    inr == AUTOFS_DEV_IOCTL_REQUESTER_CMD ||
+		    inr == AUTOFS_DEV_IOCTL_ISMOUNTPOINT_CMD) {
+			err = -EINVAL;
+			goto out;
+		}
 	}
 
 	err = 0;
@@ -271,7 +280,8 @@ static int autofs_dev_ioctl_openmount(struct file *fp,
 	dev_t devid;
 	int err, fd;
 
-	/* param->path has already been checked */
+	/* param->path has been checked in validate_dev_ioctl() */
+
 	if (!param->openmount.devid)
 		return -EINVAL;
 
@@ -433,10 +443,7 @@ static int autofs_dev_ioctl_requester(struct file *fp,
 	dev_t devid;
 	int err = -ENOENT;
 
-	if (param->size <= AUTOFS_DEV_IOCTL_SIZE) {
-		err = -EINVAL;
-		goto out;
-	}
+	/* param->path has been checked in validate_dev_ioctl() */
 
 	devid = sbi->sb->s_dev;
 
@@ -521,10 +528,7 @@ static int autofs_dev_ioctl_ismountpoint(struct file *fp,
 	unsigned int devid, magic;
 	int err = -ENOENT;
 
-	if (param->size <= AUTOFS_DEV_IOCTL_SIZE) {
-		err = -EINVAL;
-		goto out;
-	}
+	/* param->path has been checked in validate_dev_ioctl() */
 
 	name = param->path;
 	type = param->ismountpoint.in.type;
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 0ac456b52bdd..816cc921cf36 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1259,9 +1259,8 @@ static int load_elf_library(struct file *file)
 		goto out_free_ph;
 	}
 
-	len = ELF_PAGESTART(eppnt->p_filesz + eppnt->p_vaddr +
-			    ELF_MIN_ALIGN - 1);
-	bss = eppnt->p_memsz + eppnt->p_vaddr;
+	len = ELF_PAGEALIGN(eppnt->p_filesz + eppnt->p_vaddr);
+	bss = ELF_PAGEALIGN(eppnt->p_memsz + eppnt->p_vaddr);
 	if (bss > len) {
 		error = vm_brk(len, bss - len);
 		if (error)
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index e9679016271f..dfd73a4616ce 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -831,7 +831,8 @@ static int show_smap(struct seq_file *m, void *v, int is_pid)
 		SEQ_PUT_DEC(" kB\nSwap:           ", mss->swap);
 		SEQ_PUT_DEC(" kB\nSwapPss:        ",
 						mss->swap_pss >> PSS_SHIFT);
-		SEQ_PUT_DEC(" kB\nLocked:         ", mss->pss >> PSS_SHIFT);
+		SEQ_PUT_DEC(" kB\nLocked:         ",
+						mss->pss_locked >> PSS_SHIFT);
 		seq_puts(m, " kB\n");
 	}
 	if (!rollup_mode) {
diff --git a/fs/reiserfs/prints.c b/fs/reiserfs/prints.c
index 7e288d97adcb..9fed1c05f1f4 100644
--- a/fs/reiserfs/prints.c
+++ b/fs/reiserfs/prints.c
@@ -76,83 +76,99 @@ static char *le_type(struct reiserfs_key *key)
 }
 
 /* %k */
-static void sprintf_le_key(char *buf, struct reiserfs_key *key)
+static int scnprintf_le_key(char *buf, size_t size, struct reiserfs_key *key)
 {
 	if (key)
-		sprintf(buf, "[%d %d %s %s]", le32_to_cpu(key->k_dir_id),
-			le32_to_cpu(key->k_objectid), le_offset(key),
-			le_type(key));
+		return scnprintf(buf, size, "[%d %d %s %s]",
+				 le32_to_cpu(key->k_dir_id),
+				 le32_to_cpu(key->k_objectid), le_offset(key),
+				 le_type(key));
 	else
-		sprintf(buf, "[NULL]");
+		return scnprintf(buf, size, "[NULL]");
 }
 
 /* %K */
-static void sprintf_cpu_key(char *buf, struct cpu_key *key)
+static int scnprintf_cpu_key(char *buf, size_t size, struct cpu_key *key)
 {
 	if (key)
-		sprintf(buf, "[%d %d %s %s]", key->on_disk_key.k_dir_id,
-			key->on_disk_key.k_objectid, reiserfs_cpu_offset(key),
-			cpu_type(key));
+		return scnprintf(buf, size, "[%d %d %s %s]",
+				 key->on_disk_key.k_dir_id,
+				 key->on_disk_key.k_objectid,
+				 reiserfs_cpu_offset(key), cpu_type(key));
 	else
-		sprintf(buf, "[NULL]");
+		return scnprintf(buf, size, "[NULL]");
 }
 
-static void sprintf_de_head(char *buf, struct reiserfs_de_head *deh)
+static int scnprintf_de_head(char *buf, size_t size,
+			     struct reiserfs_de_head *deh)
 {
 	if (deh)
-		sprintf(buf,
-			"[offset=%d dir_id=%d objectid=%d location=%d state=%04x]",
-			deh_offset(deh), deh_dir_id(deh), deh_objectid(deh),
-			deh_location(deh), deh_state(deh));
+		return scnprintf(buf, size,
+				 "[offset=%d dir_id=%d objectid=%d location=%d state=%04x]",
+				 deh_offset(deh), deh_dir_id(deh),
+				 deh_objectid(deh), deh_location(deh),
+				 deh_state(deh));
 	else
-		sprintf(buf, "[NULL]");
+		return scnprintf(buf, size, "[NULL]");
 
 }
 
-static void sprintf_item_head(char *buf, struct item_head *ih)
+static int scnprintf_item_head(char *buf, size_t size, struct item_head *ih)
 {
 	if (ih) {
-		strcpy(buf,
-		       (ih_version(ih) == KEY_FORMAT_3_6) ? "*3.6* " : "*3.5*");
-		sprintf_le_key(buf + strlen(buf), &(ih->ih_key));
-		sprintf(buf + strlen(buf), ", item_len %d, item_location %d, "
-			"free_space(entry_count) %d",
-			ih_item_len(ih), ih_location(ih), ih_free_space(ih));
+		char *p = buf;
+		char * const end = buf + size;
+
+		p += scnprintf(p, end - p, "%s",
+			       (ih_version(ih) == KEY_FORMAT_3_6) ?
+			       "*3.6* " : "*3.5*");
+
+		p += scnprintf_le_key(p, end - p, &ih->ih_key);
+
+		p += scnprintf(p, end - p,
+			       ", item_len %d, item_location %d, free_space(entry_count) %d",
+			       ih_item_len(ih), ih_location(ih),
+			       ih_free_space(ih));
+		return p - buf;
 	} else
-		sprintf(buf, "[NULL]");
+		return scnprintf(buf, size, "[NULL]");
 }
 
-static void sprintf_direntry(char *buf, struct reiserfs_dir_entry *de)
+static int scnprintf_direntry(char *buf, size_t size,
+			      struct reiserfs_dir_entry *de)
 {
 	char name[20];
 
 	memcpy(name, de->de_name, de->de_namelen > 19 ? 19 : de->de_namelen);
 	name[de->de_namelen > 19 ? 19 : de->de_namelen] = 0;
-	sprintf(buf, "\"%s\"==>[%d %d]", name, de->de_dir_id, de->de_objectid);
+	return scnprintf(buf, size, "\"%s\"==>[%d %d]",
+			 name, de->de_dir_id, de->de_objectid);
 }
 
-static void sprintf_block_head(char *buf, struct buffer_head *bh)
+static int scnprintf_block_head(char *buf, size_t size, struct buffer_head *bh)
 {
-	sprintf(buf, "level=%d, nr_items=%d, free_space=%d rdkey ",
-		B_LEVEL(bh), B_NR_ITEMS(bh), B_FREE_SPACE(bh));
+	return scnprintf(buf, size,
+			 "level=%d, nr_items=%d, free_space=%d rdkey ",
+			 B_LEVEL(bh), B_NR_ITEMS(bh), B_FREE_SPACE(bh));
 }
 
-static void sprintf_buffer_head(char *buf, struct buffer_head *bh)
+static int scnprintf_buffer_head(char *buf, size_t size, struct buffer_head *bh)
 {
-	sprintf(buf,
-		"dev %pg, size %zd, blocknr %llu, count %d, state 0x%lx, page %p, (%s, %s, %s)",
-		bh->b_bdev, bh->b_size,
-		(unsigned long long)bh->b_blocknr, atomic_read(&(bh->b_count)),
-		bh->b_state, bh->b_page,
-		buffer_uptodate(bh) ? "UPTODATE" : "!UPTODATE",
-		buffer_dirty(bh) ? "DIRTY" : "CLEAN",
-		buffer_locked(bh) ? "LOCKED" : "UNLOCKED");
+	return scnprintf(buf, size,
+			 "dev %pg, size %zd, blocknr %llu, count %d, state 0x%lx, page %p, (%s, %s, %s)",
+			 bh->b_bdev, bh->b_size,
+			 (unsigned long long)bh->b_blocknr,
+			 atomic_read(&(bh->b_count)),
+			 bh->b_state, bh->b_page,
+			 buffer_uptodate(bh) ? "UPTODATE" : "!UPTODATE",
+			 buffer_dirty(bh) ? "DIRTY" : "CLEAN",
+			 buffer_locked(bh) ? "LOCKED" : "UNLOCKED");
 }
 
-static void sprintf_disk_child(char *buf, struct disk_child *dc)
+static int scnprintf_disk_child(char *buf, size_t size, struct disk_child *dc)
 {
-	sprintf(buf, "[dc_number=%d, dc_size=%u]", dc_block_number(dc),
-		dc_size(dc));
+	return scnprintf(buf, size, "[dc_number=%d, dc_size=%u]",
+			 dc_block_number(dc), dc_size(dc));
 }
 
 static char *is_there_reiserfs_struct(char *fmt, int *what)
@@ -189,55 +205,60 @@ static void prepare_error_buf(const char *fmt, va_list args)
 	char *fmt1 = fmt_buf;
 	char *k;
 	char *p = error_buf;
+	char * const end = &error_buf[sizeof(error_buf)];
 	int what;
 
 	spin_lock(&error_lock);
 
-	strcpy(fmt1, fmt);
+	if (WARN_ON(strscpy(fmt_buf, fmt, sizeof(fmt_buf)) < 0)) {
+		strscpy(error_buf, "format string too long", end - error_buf);
+		goto out_unlock;
+	}
 
 	while ((k = is_there_reiserfs_struct(fmt1, &what)) != NULL) {
 		*k = 0;
 
-		p += vsprintf(p, fmt1, args);
+		p += vscnprintf(p, end - p, fmt1, args);
 
 		switch (what) {
 		case 'k':
-			sprintf_le_key(p, va_arg(args, struct reiserfs_key *));
+			p += scnprintf_le_key(p, end - p,
+					      va_arg(args, struct reiserfs_key *));
 			break;
 		case 'K':
-			sprintf_cpu_key(p, va_arg(args, struct cpu_key *));
+			p += scnprintf_cpu_key(p, end - p,
+					       va_arg(args, struct cpu_key *));
 			break;
 		case 'h':
-			sprintf_item_head(p, va_arg(args, struct item_head *));
+			p += scnprintf_item_head(p, end - p,
+						 va_arg(args, struct item_head *));
 			break;
 		case 't':
-			sprintf_direntry(p,
-					 va_arg(args,
-						struct reiserfs_dir_entry *));
+			p += scnprintf_direntry(p, end - p,
+						va_arg(args, struct reiserfs_dir_entry *));
 			break;
 		case 'y':
-			sprintf_disk_child(p,
-					   va_arg(args, struct disk_child *));
+			p += scnprintf_disk_child(p, end - p,
+						  va_arg(args, struct disk_child *));
 			break;
 		case 'z':
-			sprintf_block_head(p,
-					   va_arg(args, struct buffer_head *));
+			p += scnprintf_block_head(p, end - p,
+						  va_arg(args, struct buffer_head *));
 			break;
 		case 'b':
-			sprintf_buffer_head(p,
-					    va_arg(args, struct buffer_head *));
+			p += scnprintf_buffer_head(p, end - p,
+						   va_arg(args, struct buffer_head *));
 			break;
 		case 'a':
-			sprintf_de_head(p,
-					va_arg(args,
-					       struct reiserfs_de_head *));
+			p += scnprintf_de_head(p, end - p,
+					       va_arg(args, struct reiserfs_de_head *));
 			break;
 		}
 
-		p += strlen(p);
 		fmt1 = k + 2;
 	}
-	vsprintf(p, fmt1, args);
+	p += vscnprintf(p, end - p, fmt1, args);
+out_unlock:
 	spin_unlock(&error_lock);
 
 }
diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h
index faddde44de8c..3063125197ad 100644
--- a/include/asm-generic/tlb.h
+++ b/include/asm-generic/tlb.h
@@ -265,33 +265,41 @@ static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
  * For now w.r.t page table cache, mark the range_size as PAGE_SIZE
  */
 
+#ifndef pte_free_tlb
 #define pte_free_tlb(tlb, ptep, address)			\
 	do {							\
 		__tlb_adjust_range(tlb, address, PAGE_SIZE);	\
 		__pte_free_tlb(tlb, ptep, address);		\
 	} while (0)
+#endif
 
+#ifndef pmd_free_tlb
 #define pmd_free_tlb(tlb, pmdp, address)			\
 	do {							\
 		__tlb_adjust_range(tlb, address, PAGE_SIZE);		\
 		__pmd_free_tlb(tlb, pmdp, address);		\
 	} while (0)
+#endif
 
 #ifndef __ARCH_HAS_4LEVEL_HACK
+#ifndef pud_free_tlb
 #define pud_free_tlb(tlb, pudp, address)			\
 	do {							\
 		__tlb_adjust_range(tlb, address, PAGE_SIZE);	\
 		__pud_free_tlb(tlb, pudp, address);		\
 	} while (0)
 #endif
+#endif
 
 #ifndef __ARCH_HAS_5LEVEL_HACK
+#ifndef p4d_free_tlb
 #define p4d_free_tlb(tlb, pudp, address)			\
 	do {							\
 		__tlb_adjust_range(tlb, address, PAGE_SIZE);		\
 		__p4d_free_tlb(tlb, pudp, address);		\
 	} while (0)
 #endif
+#endif
 
 #define tlb_migrate_finish(mm) do {} while (0)
 
diff --git a/mm/gup.c b/mm/gup.c
index b70d7ba7cc13..fc5f98069f4e 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1238,8 +1238,6 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors)
 	int locked = 0;
 	long ret = 0;
 
-	VM_BUG_ON(start & ~PAGE_MASK);
-	VM_BUG_ON(len != PAGE_ALIGN(len));
 	end = start + len;
 
 	for (nstart = start; nstart < end; nstart = nend) {
diff --git a/mm/memblock.c b/mm/memblock.c
index 03d48d8835ba..11e46f83e1ad 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -227,7 +227,8 @@ phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size,
 		 * so we use WARN_ONCE() here to see the stack trace if
 		 * fail happens.
 		 */
-		WARN_ONCE(1, "memblock: bottom-up allocation failed, memory hotunplug may be affected\n");
+		WARN_ONCE(IS_ENABLED(CONFIG_MEMORY_HOTREMOVE),
+			  "memblock: bottom-up allocation failed, memory hotremove may be affected\n");
 	}
 
 	return __memblock_find_range_top_down(start, end, size, align, nid,
diff --git a/mm/mmap.c b/mm/mmap.c
index d1eb87ef4b1a..5801b5f0a634 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -186,8 +186,8 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
 	return next;
 }
 
-static int do_brk(unsigned long addr, unsigned long len, struct list_head *uf);
-
+static int do_brk_flags(unsigned long addr, unsigned long request, unsigned long flags,
+		struct list_head *uf);
 SYSCALL_DEFINE1(brk, unsigned long, brk)
 {
 	unsigned long retval;
@@ -245,7 +245,7 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 		goto out;
 
 	/* Ok, looks good - let it rip. */
-	if (do_brk(oldbrk, newbrk-oldbrk, &uf) < 0)
+	if (do_brk_flags(oldbrk, newbrk-oldbrk, 0, &uf) < 0)
 		goto out;
 
 set_brk:
@@ -2929,21 +2929,14 @@ static inline void verify_mm_writelocked(struct mm_struct *mm)
  *  anonymous maps.  eventually we may be able to do some
  *  brk-specific accounting here.
  */
-static int do_brk_flags(unsigned long addr, unsigned long request, unsigned long flags, struct list_head *uf)
+static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long flags, struct list_head *uf)
 {
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma, *prev;
-	unsigned long len;
 	struct rb_node **rb_link, *rb_parent;
 	pgoff_t pgoff = addr >> PAGE_SHIFT;
 	int error;
 
-	len = PAGE_ALIGN(request);
-	if (len < request)
-		return -ENOMEM;
-	if (!len)
-		return 0;
-
 	/* Until we need other flags, refuse anything except VM_EXEC. */
 	if ((flags & (~VM_EXEC)) != 0)
 		return -EINVAL;
@@ -3015,18 +3008,20 @@ out:
 	return 0;
 }
 
-static int do_brk(unsigned long addr, unsigned long len, struct list_head *uf)
-{
-	return do_brk_flags(addr, len, 0, uf);
-}
-
-int vm_brk_flags(unsigned long addr, unsigned long len, unsigned long flags)
+int vm_brk_flags(unsigned long addr, unsigned long request, unsigned long flags)
 {
 	struct mm_struct *mm = current->mm;
+	unsigned long len;
 	int ret;
 	bool populate;
 	LIST_HEAD(uf);
 
+	len = PAGE_ALIGN(request);
+	if (len < request)
+		return -ENOMEM;
+	if (!len)
+		return 0;
+
 	if (down_write_killable(&mm->mmap_sem))
 		return -EINTR;
 
diff --git a/mm/rmap.c b/mm/rmap.c
index 6db729dc4c50..eb477809a5c0 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -64,6 +64,7 @@
 #include <linux/backing-dev.h>
 #include <linux/page_idle.h>
 #include <linux/memremap.h>
+#include <linux/userfaultfd_k.h>
 
 #include <asm/tlbflush.h>
 
@@ -1481,11 +1482,16 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 				set_pte_at(mm, address, pvmw.pte, pteval);
 			}
 
-		} else if (pte_unused(pteval)) {
+		} else if (pte_unused(pteval) && !userfaultfd_armed(vma)) {
 			/*
 			 * The guest indicated that the page content is of no
 			 * interest anymore. Simply discard the pte, vmscan
 			 * will take care of the rest.
+			 * A future reference will then fault in a new zero
+			 * page. When userfaultfd is active, we must not drop
+			 * this page though, as its main user (postcopy
+			 * migration) will not expect userfaults on already
+			 * copied pages.
 			 */
 			dec_mm_counter(mm, mm_counter(page));
 			/* We have to invalidate as we cleared the pte */
diff --git a/net/9p/client.c b/net/9p/client.c
index 18c5271910dc..5c1343195292 100644
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@ -225,7 +225,8 @@ static int parse_opts(char *opts, struct p9_client *clnt)
 	}
 
 free_and_return:
-	v9fs_put_trans(clnt->trans_mod);
+	if (ret)
+		v9fs_put_trans(clnt->trans_mod);
 	kfree(tmp_options);
 	return ret;
 }
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index a9c05506e325..447857ffaf6b 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -5813,14 +5813,14 @@ sub process {
 		    defined $stat &&
 		    $stat =~ /^\+(?![^\{]*\{\s*).*\b(\w+)\s*\(.*$String\s*,/s &&
 		    $1 !~ /^_*volatile_*$/) {
-			my $specifier;
-			my $extension;
-			my $bad_specifier = "";
 			my $stat_real;
 
 			my $lc = $stat =~ tr@\n@@;
 			$lc = $lc + $linenr;
 		        for (my $count = $linenr; $count <= $lc; $count++) {
+				my $specifier;
+				my $extension;
+				my $bad_specifier = "";
 				my $fmt = get_quoted_string($lines[$count - 1], raw_line($count, 0));
 				$fmt =~ s/%%//g;