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authorDarrick J. Wong <darrick.wong@oracle.com>2018-10-30 10:40:31 +1100
committerDave Chinner <david@fromorbit.com>2018-10-30 10:40:31 +1100
commit1383a7ed67490fb00d793e36c7a4d599ff88a64d (patch)
tree048373f94325388a84358370707718d5c15366a6 /fs/read_write.c
parent5b49f64db299d0b3f7c2170088186aa593d0be7d (diff)
vfs: check file ranges before cloning files
Move the file range checks from vfs_clone_file_prep into a separate generic_remap_checks function so that all the checks are collected in a central location. This forms the basis for adding more checks from generic_write_checks that will make cloning's input checking more consistent with write input checking. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
Diffstat (limited to 'fs/read_write.c')
-rw-r--r--fs/read_write.c55
1 files changed, 13 insertions, 42 deletions
diff --git a/fs/read_write.c b/fs/read_write.c
index 260797b01851..d6e8e242a15f 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1717,13 +1717,12 @@ static int clone_verify_area(struct file *file, loff_t pos, u64 len, bool write)
* Returns: 0 for "nothing to clone", 1 for "something to clone", or
* the usual negative error code.
*/
-int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
- struct inode *inode_out, loff_t pos_out,
- u64 *len, bool is_dedupe)
+int vfs_clone_file_prep(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ u64 *len, bool is_dedupe)
{
- loff_t bs = inode_out->i_sb->s_blocksize;
- loff_t blen;
- loff_t isize;
+ struct inode *inode_in = file_inode(file_in);
+ struct inode *inode_out = file_inode(file_out);
bool same_inode = (inode_in == inode_out);
int ret;
@@ -1740,10 +1739,10 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
return -EINVAL;
- isize = i_size_read(inode_in);
-
/* Zero length dedupe exits immediately; reflink goes to EOF. */
if (*len == 0) {
+ loff_t isize = i_size_read(inode_in);
+
if (is_dedupe || pos_in == isize)
return 0;
if (pos_in > isize)
@@ -1751,36 +1750,11 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
*len = isize - pos_in;
}
- /* Ensure offsets don't wrap and the input is inside i_size */
- if (pos_in + *len < pos_in || pos_out + *len < pos_out ||
- pos_in + *len > isize)
- return -EINVAL;
-
- /* Don't allow dedupe past EOF in the dest file */
- if (is_dedupe) {
- loff_t disize;
-
- disize = i_size_read(inode_out);
- if (pos_out >= disize || pos_out + *len > disize)
- return -EINVAL;
- }
-
- /* If we're linking to EOF, continue to the block boundary. */
- if (pos_in + *len == isize)
- blen = ALIGN(isize, bs) - pos_in;
- else
- blen = *len;
-
- /* Only reflink if we're aligned to block boundaries */
- if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_in + blen, bs) ||
- !IS_ALIGNED(pos_out, bs) || !IS_ALIGNED(pos_out + blen, bs))
- return -EINVAL;
-
- /* Don't allow overlapped reflink within the same file */
- if (same_inode) {
- if (pos_out + blen > pos_in && pos_out < pos_in + blen)
- return -EINVAL;
- }
+ /* Check that we don't violate system file offset limits. */
+ ret = generic_remap_checks(file_in, pos_in, file_out, pos_out, len,
+ is_dedupe);
+ if (ret)
+ return ret;
/* Wait for the completion of any pending IOs on both files */
inode_dio_wait(inode_in);
@@ -1813,7 +1787,7 @@ int vfs_clone_file_prep_inodes(struct inode *inode_in, loff_t pos_in,
return 1;
}
-EXPORT_SYMBOL(vfs_clone_file_prep_inodes);
+EXPORT_SYMBOL(vfs_clone_file_prep);
int do_clone_file_range(struct file *file_in, loff_t pos_in,
struct file *file_out, loff_t pos_out, u64 len)
@@ -1851,9 +1825,6 @@ int do_clone_file_range(struct file *file_in, loff_t pos_in,
if (ret)
return ret;
- if (pos_in + len > i_size_read(inode_in))
- return -EINVAL;
-
ret = file_in->f_op->clone_file_range(file_in, pos_in,
file_out, pos_out, len);
if (!ret) {