| Message ID | 4B03A192.5000201@rs.jp.nec.com |
|---|---|
| State | Accepted, archived |
| Headers | show |
On Wed, Nov 18, 2009 at 04:26:10PM +0900, Akira Fujita wrote: > ext4: initialize moved_len before calling ext4_move_extents() > > From: Kazuya Mio <k-mio@sx.jp.nec.com> > > moved_len of struct move_extent is used to notify > exchanged blocks count to the user space. > So at the beginning of the EXT4_IOC_MOVE_EXT, > moved_len should be always zero. > Without this patch, if wrong moved_len is passed from the user space, > EXT4_IOC_MOVE_EXT will return wrong blocks count. Applied with the following rewording of the patch description: ext4: initialize moved_len before calling ext4_move_extents() From: Kazuya Mio <k-mio@sx.jp.nec.com> The move_extent.moved_len is used to pass back the number of exchanged blocks count to user space. Currently the caller must clear this field; but we spend more code space checking for this requirement than simply zeroing the field ourselves, so let's just make life easier for everyone all around. Signed-off-by: Kazuya Mio <k-mio@sx.jp.nec.com> Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c index d1fe495..dbf9a8b 100644 --- a/fs/ext4/ioctl.c +++ b/fs/ext4/ioctl.c @@ -251,6 +251,7 @@ setversion_out: } } + me.moved_len = 0; err = ext4_move_extents(filp, donor_filp, me.orig_start, me.donor_start, me.len, &me.moved_len); fput(donor_filp); diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c index 25b6b14..e2e99fd 100644 --- a/fs/ext4/move_extent.c +++ b/fs/ext4/move_extent.c @@ -962,7 +962,6 @@ out2: * @orig_start: logical start offset in block for orig * @donor_start: logical start offset in block for donor * @len: the number of blocks to be moved - * @moved_len: moved block length * * Check the arguments of ext4_move_extents() whether the files can be * exchanged with each other. @@ -971,7 +970,7 @@ out2: static int mext_check_arguments(struct inode *orig_inode, struct inode *donor_inode, __u64 orig_start, - __u64 donor_start, __u64 *len, __u64 moved_len) + __u64 donor_start, __u64 *len) { ext4_lblk_t orig_blocks, donor_blocks; unsigned int blkbits = orig_inode->i_blkbits; @@ -1025,13 +1024,6 @@ mext_check_arguments(struct inode *orig_inode, return -EINVAL; } - if (moved_len) { - ext4_debug("ext4 move extent: moved_len should be 0 " - "[ino:orig %lu, donor %lu]\n", orig_inode->i_ino, - donor_inode->i_ino); - return -EINVAL; - } - if ((orig_start > EXT_MAX_BLOCK) || (donor_start > EXT_MAX_BLOCK) || (*len > EXT_MAX_BLOCK) || @@ -1240,7 +1232,7 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, mext_double_down_read(orig_inode, donor_inode); /* Check the filesystem environment whether move_extent can be done */ ret1 = mext_check_arguments(orig_inode, donor_inode, orig_start, - donor_start, &len, *moved_len); + donor_start, &len); mext_double_up_read(orig_inode, donor_inode); if (ret1) goto out;