Merge branch 'rdma_mmap' into rdma.git for-next

Jason Gunthorpe says:

====================
Upon review it turns out there are some long standing problems in BAR
mapping area:
 * BAR pages intended for read-only can be switched to writable via mprotect.
 * Missing use of rdma_user_mmap_io for the mlx5 clock BAR page.
 * Disassociate causes SIGBUS when touching the pages.
 * CPU pages are being mapped through to the process via remap_pfn_range
   instead of the more appropriate vm_insert_page, causing weird behaviors
   during disassociation.

This series adds the missing VM_* flag manipulation, adds faulting a zero
page for disassociation and revises the CPU page mappings to use
vm_insert_page.
====================

For dependencies this branch is based on for-rc from
git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git

* branch 'rdma_mmap':
  RDMA: Remove rdma_user_mmap_page
  RDMA/mlx5: Use get_zeroed_page() for clock_info
  RDMA/ucontext: Fix regression with disassociate
  RDMA/mlx5: Use rdma_user_map_io for mapping BAR pages
  RDMA/mlx5: Do not allow the user to write to the clock page

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 25 insertions, 20 deletions

diff --git a/drivers/staging/erofs/dir.c b/drivers/staging/erofs/dir.c
index 829f7b12e0dc..9bbc68729c11 100644
--- a/drivers/staging/erofs/dir.c
+++ b/drivers/staging/erofs/dir.c
@@ -23,6 +23,21 @@ static const unsigned char erofs_filetype_table[EROFS_FT_MAX] = {
 	[EROFS_FT_SYMLINK]	= DT_LNK,
 };
 
+static void debug_one_dentry(unsigned char d_type, const char *de_name,
+			     unsigned int de_namelen)
+{
+#ifdef CONFIG_EROFS_FS_DEBUG
+	/* since the on-disk name could not have the trailing '\0' */
+	unsigned char dbg_namebuf[EROFS_NAME_LEN + 1];
+
+	memcpy(dbg_namebuf, de_name, de_namelen);
+	dbg_namebuf[de_namelen] = '\0';
+
+	debugln("found dirent %s de_len %u d_type %d", dbg_namebuf,
+		de_namelen, d_type);
+#endif
+}
+
 static int erofs_fill_dentries(struct dir_context *ctx,
 			       void *dentry_blk, unsigned int *ofs,
 			       unsigned int nameoff, unsigned int maxsize)
@@ -33,14 +48,10 @@ static int erofs_fill_dentries(struct dir_context *ctx,
 	de = dentry_blk + *ofs;
 	while (de < end) {
 		const char *de_name;
-		int de_namelen;
+		unsigned int de_namelen;
 		unsigned char d_type;
-#ifdef CONFIG_EROFS_FS_DEBUG
-		unsigned int dbg_namelen;
-		unsigned char dbg_namebuf[EROFS_NAME_LEN];
-#endif
 
-		if (unlikely(de->file_type < EROFS_FT_MAX))
+		if (de->file_type < EROFS_FT_MAX)
 			d_type = erofs_filetype_table[de->file_type];
 		else
 			d_type = DT_UNKNOWN;
@@ -48,26 +59,20 @@ static int erofs_fill_dentries(struct dir_context *ctx,
 		nameoff = le16_to_cpu(de->nameoff);
 		de_name = (char *)dentry_blk + nameoff;
 
-		de_namelen = unlikely(de + 1 >= end) ?
-			/* last directory entry */
-			strnlen(de_name, maxsize - nameoff) :
-			le16_to_cpu(de[1].nameoff) - nameoff;
+		/* the last dirent in the block? */
+		if (de + 1 >= end)
+			de_namelen = strnlen(de_name, maxsize - nameoff);
+		else
+			de_namelen = le16_to_cpu(de[1].nameoff) - nameoff;
 
 		/* a corrupted entry is found */
-		if (unlikely(de_namelen < 0)) {
+		if (unlikely(nameoff + de_namelen > maxsize ||
+			     de_namelen > EROFS_NAME_LEN)) {
 			DBG_BUGON(1);
 			return -EIO;
 		}
 
-#ifdef CONFIG_EROFS_FS_DEBUG
-		dbg_namelen = min(EROFS_NAME_LEN - 1, de_namelen);
-		memcpy(dbg_namebuf, de_name, dbg_namelen);
-		dbg_namebuf[dbg_namelen] = '\0';
-
-		debugln("%s, found de_name %s de_len %d d_type %d", __func__,
-			dbg_namebuf, de_namelen, d_type);
-#endif
-
+		debug_one_dentry(d_type, de_name, de_namelen);
 		if (!dir_emit(ctx, de_name, de_namelen,
 			      le64_to_cpu(de->nid), d_type))
 			/* stopped by some reason */