Hi Yunlei,

On Tue, Mar 02, 2021 at 07:38:50PM +0800, Yunlei He wrote:

If file enable verity failed, should truncate anything wrote past i_size, including cache pages. Move the truncation to the end of function, in case of f2fs set xattr failed.

Fixes: 95ae251fe828 ("f2fs: add fs-verity support") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Yunlei He heyunlei@hihonor.com

---

fs/f2fs/verity.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/fs/f2fs/verity.c b/fs/f2fs/verity.c index 054ec852b5ea..610f2a9b4928 100644 --- a/fs/f2fs/verity.c +++ b/fs/f2fs/verity.c @@ -169,10 +169,6 @@ static int f2fs_end_enable_verity(struct file *filp, const void *desc, err = filemap_write_and_wait(inode->i_mapping); }

• /* If we failed, truncate anything we wrote past i_size. */
• if (desc == NULL || err)

• f2fs_truncate(inode);
  

• clear_inode_flag(inode, FI_VERITY_IN_PROGRESS);

if (desc != NULL && !err) { @@ -185,6 +181,13 @@ static int f2fs_end_enable_verity(struct file *filp, const void *desc, f2fs_mark_inode_dirty_sync(inode, true); } }

• /* If we failed, truncate anything we wrote past i_size. */
• if (desc == NULL || err) {

• truncate_inode_pages(inode->i_mapping, inode->i_size);
  

• f2fs_truncate(inode);
  

• }
• return err;

This is better, but we really should properly separate the success path from the error paths in this function; otherwise it's too hard to understand. Also, the same bugs need to be fixed in ext4 too, and the commit message could be better. I went ahead and sent out a new patchset which addresses all this (https://lkml.kernel.org/linux-f2fs-devel/20210302200420.137977-1-ebiggers@ke...); can you take a look at that instead? Thanks!

- Eric