From: Al Viro <viro@zeniv.linux.org.uk>
Date: Wed, 10 Feb 2021 21:23:04 -0500
Subject: [PATCH] cifs: have cifs_fattr_to_inode() refuse to change type on
live inode
Git-commit: 4d66952a2032cf6b65183fc4a8d8039304c70d48
Patch-mainline: v5.13-rc1
References: bsc#1192606
... instead of trying to do that in the callers (and missing some,
at that)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Enzo Matsumiya <ematsumiya@suse.de>
---
fs/cifs/cifsproto.h | 2 +-
fs/cifs/file.c | 2 +-
fs/cifs/inode.c | 42 +++++++++++++++---------------------------
fs/cifs/readdir.c | 4 +---
4 files changed, 18 insertions(+), 32 deletions(-)
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -194,7 +194,7 @@ extern void cifs_unix_basic_to_fattr(str
struct cifs_sb_info *cifs_sb);
extern void cifs_dir_info_to_fattr(struct cifs_fattr *, FILE_DIRECTORY_INFO *,
struct cifs_sb_info *);
-extern void cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr);
+extern int cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr);
extern struct inode *cifs_iget(struct super_block *sb,
struct cifs_fattr *fattr);
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -166,7 +166,7 @@ int cifs_posix_open(char *full_path, str
}
} else {
cifs_revalidate_mapping(*pinode);
- cifs_fattr_to_inode(*pinode, &fattr);
+ rc = cifs_fattr_to_inode(*pinode, &fattr);
}
posix_open_ret:
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -155,12 +155,18 @@ cifs_nlink_fattr_to_inode(struct inode *
}
/* populate an inode with info from a cifs_fattr struct */
-void
+int
cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
{
struct cifsInodeInfo *cifs_i = CIFS_I(inode);
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
+ if (!(inode->i_state & I_NEW) &&
+ unlikely((inode->i_mode ^ fattr->cf_mode) & S_IFMT)) {
+ CIFS_I(inode)->time = 0; /* force reval */
+ return -ESTALE;
+ }
+
cifs_revalidate_cache(inode, fattr);
spin_lock(&inode->i_lock);
@@ -214,6 +220,7 @@ cifs_fattr_to_inode(struct inode *inode,
inode->i_flags |= S_AUTOMOUNT;
if (inode->i_state & I_NEW)
cifs_set_ops(inode);
+ return 0;
}
void
@@ -359,7 +366,7 @@ cifs_get_file_info_unix(struct file *fil
rc = 0;
}
- cifs_fattr_to_inode(inode, &fattr);
+ rc = cifs_fattr_to_inode(inode, &fattr);
free_xid(xid);
return rc;
}
@@ -422,14 +429,7 @@ int cifs_get_inode_info_unix(struct inod
}
/* if filetype is different, return error */
- if (unlikely(((*pinode)->i_mode & S_IFMT) !=
- (fattr.cf_mode & S_IFMT))) {
- CIFS_I(*pinode)->time = 0; /* force reval */
- rc = -ESTALE;
- goto cgiiu_exit;
- }
-
- cifs_fattr_to_inode(*pinode, &fattr);
+ rc = cifs_fattr_to_inode(*pinode, &fattr);
}
cgiiu_exit:
@@ -781,7 +781,8 @@ cifs_get_file_info(struct file *filp)
*/
fattr.cf_uniqueid = CIFS_I(inode)->uniqueid;
fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
- cifs_fattr_to_inode(inode, &fattr);
+ /* if filetype is different, return error */
+ rc = cifs_fattr_to_inode(inode, &fattr);
cgfi_exit:
free_xid(xid);
return rc;
@@ -1098,16 +1099,8 @@ handle_mnt_opt:
rc = -ESTALE;
goto out;
}
-
/* if filetype is different, return error */
- if (unlikely(((*inode)->i_mode & S_IFMT) !=
- (fattr.cf_mode & S_IFMT))) {
- CIFS_I(*inode)->time = 0; /* force reval */
- rc = -ESTALE;
- goto out;
- }
-
- cifs_fattr_to_inode(*inode, &fattr);
+ rc = cifs_fattr_to_inode(*inode, &fattr);
}
out:
cifs_buf_release(smb1_backup_rsp_buf);
@@ -1213,14 +1206,7 @@ smb311_posix_get_inode_info(struct inode
}
/* if filetype is different, return error */
- if (unlikely(((*inode)->i_mode & S_IFMT) !=
- (fattr.cf_mode & S_IFMT))) {
- CIFS_I(*inode)->time = 0; /* force reval */
- rc = -ESTALE;
- goto out;
- }
-
- cifs_fattr_to_inode(*inode, &fattr);
+ rc = cifs_fattr_to_inode(*inode, &fattr);
}
out:
cifs_put_tlink(tlink);
@@ -1315,6 +1301,7 @@ retry_iget5_locked:
}
}
+ /* can't fail - see cifs_find_inode() */
cifs_fattr_to_inode(inode, fattr);
if (sb->s_flags & SB_NOATIME)
inode->i_flags |= S_NOATIME | S_NOCMTIME;
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -119,9 +119,7 @@ retry:
/* update inode in place
* if both i_ino and i_mode didn't change */
if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid &&
- (inode->i_mode & S_IFMT) ==
- (fattr->cf_mode & S_IFMT)) {
- cifs_fattr_to_inode(inode, fattr);
+ cifs_fattr_to_inode(inode, fattr) == 0) {
dput(dentry);
return;
}