1 files changed, 26 insertions, 3 deletions

diff --git a/fs/open.c b/fs/open.c
index b9ed8b25c108..631aea815def 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -231,7 +231,13 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
                 return -EINVAL;
 
         /* Return error if mode is not supported */
-        if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
+        if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
+                     FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE))
+                return -EOPNOTSUPP;
+
+        /* Punch hole and zero range are mutually exclusive */
+        if ((mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE)) ==
+            (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_ZERO_RANGE))
                 return -EOPNOTSUPP;
 
         /* Punch hole must have keep size set */
@@ -239,11 +245,20 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
             !(mode & FALLOC_FL_KEEP_SIZE))
                 return -EOPNOTSUPP;
 
+        /* Collapse range should only be used exclusively. */
+        if ((mode & FALLOC_FL_COLLAPSE_RANGE) &&
+            (mode & ~FALLOC_FL_COLLAPSE_RANGE))
+                return -EINVAL;
+
         if (!(file->f_mode & FMODE_WRITE))
                 return -EBADF;
 
-        /* It's not possible punch hole on append only file */
-        if (mode & FALLOC_FL_PUNCH_HOLE && IS_APPEND(inode))
+        /*
+         * It's not possible to punch hole or perform collapse range
+         * on append only file
+         */
+        if (mode & (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_COLLAPSE_RANGE)
+            && IS_APPEND(inode))
                 return -EPERM;
 
         if (IS_IMMUTABLE(inode))
@@ -271,6 +286,14 @@ int do_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
         if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0))
                 return -EFBIG;
 
+        /*
+         * There is no need to overlap collapse range with EOF, in which case
+         * it is effectively a truncate operation
+         */
+        if ((mode & FALLOC_FL_COLLAPSE_RANGE) &&
+            (offset + len >= i_size_read(inode)))
+                return -EINVAL;
+
         if (!file->f_op->fallocate)
                 return -EOPNOTSUPP;