From 74d290da476f672ad756634d12aa707375d3564d Mon Sep 17 00:00:00 2001 From: Jim McDonough Date: Sat, 21 Sep 2013 10:36:10 -0500 Subject: [CIFS] Provide sane values for nlink Since we don't get info about the number of links from the readdir linfo levels, stat() will return 0 for st_nlink, and in particular, samba re-exported shares will show directories as files (as samba is keying off st_nlink before evaluating how to set the dos modebits) when doing a dir or ls. Copy nlink to the inode, unless it wasn't provided. Provide sane values if we don't have an existing one and none was provided. Signed-off-by: Jim McDonough Reviewed-by: Jeff Layton Reviewed-by: David Disseldorp Signed-off-by: Steve French --- fs/cifs/cifsglob.h | 1 + fs/cifs/inode.c | 45 +++++++++++++++++++++++++++++++++++++++------ fs/cifs/readdir.c | 3 +++ 3 files changed, 43 insertions(+), 6 deletions(-) (limited to 'fs/cifs') diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 9c72be6fb0df..52b6f6c26bfc 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -1268,6 +1268,7 @@ struct dfs_info3_param { #define CIFS_FATTR_DELETE_PENDING 0x2 #define CIFS_FATTR_NEED_REVAL 0x4 #define CIFS_FATTR_INO_COLLISION 0x8 +#define CIFS_FATTR_UNKNOWN_NLINK 0x10 struct cifs_fattr { u32 cf_flags; diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index f9ff9c173f78..867b7cdc794a 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -120,6 +120,33 @@ cifs_revalidate_cache(struct inode *inode, struct cifs_fattr *fattr) cifs_i->invalid_mapping = true; } +/* + * copy nlink to the inode, unless it wasn't provided. Provide + * sane values if we don't have an existing one and none was provided + */ +static void +cifs_nlink_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr) +{ + /* + * if we're in a situation where we can't trust what we + * got from the server (readdir, some non-unix cases) + * fake reasonable values + */ + if (fattr->cf_flags & CIFS_FATTR_UNKNOWN_NLINK) { + /* only provide fake values on a new inode */ + if (inode->i_state & I_NEW) { + if (fattr->cf_cifsattrs & ATTR_DIRECTORY) + set_nlink(inode, 2); + else + set_nlink(inode, 1); + } + return; + } + + /* we trust the server, so update it */ + set_nlink(inode, fattr->cf_nlink); +} + /* populate an inode with info from a cifs_fattr struct */ void cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr) @@ -134,7 +161,7 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr) inode->i_mtime = fattr->cf_mtime; inode->i_ctime = fattr->cf_ctime; inode->i_rdev = fattr->cf_rdev; - set_nlink(inode, fattr->cf_nlink); + cifs_nlink_fattr_to_inode(inode, fattr); inode->i_uid = fattr->cf_uid; inode->i_gid = fattr->cf_gid; @@ -541,6 +568,7 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info, fattr->cf_bytes = le64_to_cpu(info->AllocationSize); fattr->cf_createtime = le64_to_cpu(info->CreationTime); + fattr->cf_nlink = le32_to_cpu(info->NumberOfLinks); if (fattr->cf_cifsattrs & ATTR_DIRECTORY) { fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode; fattr->cf_dtype = DT_DIR; @@ -548,7 +576,8 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info, * Server can return wrong NumberOfLinks value for directories * when Unix extensions are disabled - fake it. */ - fattr->cf_nlink = 2; + if (!tcon->unix_ext) + fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK; } else if (fattr->cf_cifsattrs & ATTR_REPARSE) { fattr->cf_mode = S_IFLNK; fattr->cf_dtype = DT_LNK; @@ -561,11 +590,15 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info, if (fattr->cf_cifsattrs & ATTR_READONLY) fattr->cf_mode &= ~(S_IWUGO); - fattr->cf_nlink = le32_to_cpu(info->NumberOfLinks); - if (fattr->cf_nlink < 1) { - cifs_dbg(1, "replacing bogus file nlink value %u\n", + /* + * Don't accept zero nlink from non-unix servers unless + * delete is pending. Instead mark it as unknown. + */ + if ((fattr->cf_nlink < 1) && !tcon->unix_ext && + !info->DeletePending) { + cifs_dbg(1, "bogus file nlink value %u\n", fattr->cf_nlink); - fattr->cf_nlink = 1; + fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK; } } diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c index 42ef03be089f..53a75f3d0179 100644 --- a/fs/cifs/readdir.c +++ b/fs/cifs/readdir.c @@ -180,6 +180,9 @@ cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb) fattr->cf_dtype = DT_REG; } + /* non-unix readdir doesn't provide nlink */ + fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK; + if (fattr->cf_cifsattrs & ATTR_READONLY) fattr->cf_mode &= ~S_IWUGO; -- cgit v1.2.3