vfs: Return -ENXIO for negative SEEK_HOLE / SEEK_DATA offsets
authorAndreas Gruenbacher <agruenba@redhat.com>
Mon, 25 Sep 2017 10:23:03 +0000 (12:23 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 5 Oct 2017 07:41:45 +0000 (09:41 +0200)
commit fc46820b27a2d9a46f7e90c9ceb4a64a1bc5fab8 upstream.

In generic_file_llseek_size, return -ENXIO for negative offsets as well
as offsets beyond EOF.  This affects filesystems which don't implement
SEEK_HOLE / SEEK_DATA internally, possibly because they don't support
holes.

Fixes xfstest generic/448.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/read_write.c

index 819ef3f..bfd1a5d 100644 (file)
@@ -112,7 +112,7 @@ generic_file_llseek_size(struct file *file, loff_t offset, int whence,
                 * In the generic case the entire file is data, so as long as
                 * offset isn't at the end of the file then the offset is data.
                 */
-               if (offset >= eof)
+               if ((unsigned long long)offset >= eof)
                        return -ENXIO;
                break;
        case SEEK_HOLE:
@@ -120,7 +120,7 @@ generic_file_llseek_size(struct file *file, loff_t offset, int whence,
                 * There is a virtual hole at the end of the file, so as long as
                 * offset isn't i_size or larger, return i_size.
                 */
-               if (offset >= eof)
+               if ((unsigned long long)offset >= eof)
                        return -ENXIO;
                offset = eof;
                break;