On 10/18/18 3:46 PM, jeffm@xxxxxxxx wrote:
> From: Jeff Mahoney <jeffm@xxxxxxxx>
>
> If a directory entry has been corrupted such that the flags reflect
> a different visibility state than expected, we will panic the node.
>
> This patch instead returns -EIO and sets the file system read-only.
>
> Signed-off-by: Jeff Mahoney <jeffm@xxxxxxxx>
> ---
> fs/reiserfs/namei.c | 108 ++++++++++++++++++++++++++++++++--------------------
> 1 file changed, 67 insertions(+), 41 deletions(-)
>
> diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c
> index 5be509a9204f..01e788f91a1d 100644
> --- a/fs/reiserfs/namei.c
> +++ b/fs/reiserfs/namei.c
> @@ -1254,7 +1254,7 @@ static int reiserfs_link(struct dentry *old_dentry, struct inode *dir,
>
> /* de contains information pointing to an entry which */
> static int de_still_valid(const char *name, int len,
> - struct reiserfs_dir_entry *de)
> + const struct reiserfs_dir_entry *de)
> {
> struct reiserfs_dir_entry tmp = *de;
>
> @@ -1266,23 +1266,31 @@ static int de_still_valid(const char *name, int len,
> return 1;
> }
>
> -static int entry_points_to_object(const char *name, int len,
> - struct reiserfs_dir_entry *de,
> - struct inode *inode)
> +static int entry_points_to_object(const struct inode *dir,
> + const char *name, int len,
> + const struct reiserfs_dir_entry *de,
> + const struct inode *inode)
> {
> if (!de_still_valid(name, len, de))
> return 0;
>
> if (inode) {
> - if (!de_visible(de->de_deh + de->de_entry_num))
> - reiserfs_panic(inode->i_sb, "vs-7042",
> - "entry must be visible");
> + if (!de_visible(de->de_deh + de->de_entry_num)) {
> + reiserfs_error(dir->i_sb, "vs-7042",
> + "entry must be visible (%.*s in dir %k",
> + len, name, INODE_PKEY(dir));
> + return -EIO;
> + }
> return (de->de_objectid == inode->i_ino) ? 1 : 0;
> }
>
> /* this must be added hidden entry */
> - if (de_visible(de->de_deh + de->de_entry_num))
> - reiserfs_panic(NULL, "vs-7043", "entry must be invisible");
> + if (de_visible(de->de_deh + de->de_entry_num)) {
> + reiserfs_error(dir->i_sb, "vs-7043",
> + "entry must be invisible (%.*s in dir %k",
> + len, name, INODE_PKEY(dir));
> + return -EIO;
> + }
>
> return 1;
> }
> @@ -1541,47 +1549,65 @@ static int reiserfs_rename(struct inode *old_dir, struct dentry *old_dentry,
> * of the above checks could have scheduled. We have to be
> * sure our items haven't been shifted by another process.
> */
> - if (item_moved(&new_entry_ih, &new_entry_path) ||
> - !entry_points_to_object(new_dentry->d_name.name,
> - new_dentry->d_name.len,
> - &new_de, new_dentry_inode) ||
> - item_moved(&old_entry_ih, &old_entry_path) ||
> - !entry_points_to_object(old_dentry->d_name.name,
> - old_dentry->d_name.len,
> - &old_de, old_inode)) {
> - reiserfs_restore_prepared_buffer(old_inode->i_sb,
> - new_de.de_bh);
> - reiserfs_restore_prepared_buffer(old_inode->i_sb,
> - old_de.de_bh);
> - if (S_ISDIR(old_inode_mode))
> - reiserfs_restore_prepared_buffer(old_inode->
> - i_sb,
> - dot_dot_de.
> - de_bh);
> - continue;
> + if (item_moved(&new_entry_ih, &new_entry_path)) {
> + retval = 0;
> + goto restore;
> }
> +
> + retval = entry_points_to_object(new_dir,
> + new_dentry->d_name.name,
> + new_dentry->d_name.len,
> + &new_de, new_dentry_inode);
> + if (retval != 1)
> + goto restore;
> +
> + if (item_moved(&old_entry_ih, &old_entry_path)) {
> + retval = 0;
> + goto restore;
> + }
> +
> + retval = entry_points_to_object(old_dir,
> + old_dentry->d_name.name,
> + old_dentry->d_name.len,
> + &old_de, old_inode);
> + if (retval != 1)
> + goto restore;
> +
> if (S_ISDIR(old_inode_mode)) {
> - if (item_moved(&dot_dot_ih, &dot_dot_entry_path) ||
> - !entry_points_to_object("..", 2, &dot_dot_de,
> - old_dir)) {
> - reiserfs_restore_prepared_buffer(old_inode->
> - i_sb,
> - old_de.de_bh);
> - reiserfs_restore_prepared_buffer(old_inode->
> - i_sb,
> - new_de.de_bh);
> - reiserfs_restore_prepared_buffer(old_inode->
> - i_sb,
> - dot_dot_de.
> - de_bh);
> - continue;
> + if (item_moved(&dot_dot_ih, &dot_dot_entry_path)) {
> + retval = 0;
> + goto restore;
> }
> +
> + retval = entry_points_to_object(old_dir, "..", 2,
> + &dot_dot_de, old_dir);
> + if (retval != 1)
> + goto restore;
> }
>
> + retval = 0;
> +
> RFALSE(S_ISDIR(old_inode_mode) &&
> !buffer_journal_prepared(dot_dot_de.de_bh), "");
>
> break;
> +
> +restore:
> + reiserfs_restore_prepared_buffer(old_inode->i_sb,
> + new_de.de_bh);
> + reiserfs_restore_prepared_buffer(old_inode->i_sb,
> + old_de.de_bh);
> + if (S_ISDIR(old_inode_mode))
> + reiserfs_restore_prepared_buffer(old_inode->i_sb,
> + dot_dot_de.de_bh);
> + if (retval) {
> + pathrelse(&dot_dot_entry_path);
> + pathrelse(&new_entry_path);
> + pathrelse(&old_entry_path);
> + journal_end(&th, old_dir->i_sb, jbegin_count);
Well that's not gonna work...
-Jeff
> + reiserfs_write_unlock(old_dir->i_sb);
> + return retval;
> + }
> }
>
> /*
>
--
Jeff Mahoney
SUSE Labs
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