From 7ea884c77e5c97f1e0a1a422d961d27f78ca2745 Mon Sep 17 00:00:00 2001 From: Steve French Date: Sat, 31 Mar 2018 18:13:38 -0500 Subject: smb3: Fix root directory when server returns inode number of zero Some servers return inode number zero for the root directory, which causes ls to display incorrect data (missing "." and ".."). If the server returns zero for the inode number of the root directory, fake an inode number for it. Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky CC: Stable --- fs/cifs/inode.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'fs/cifs/inode.c') diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index c98a852180b1..f856df4adae3 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -707,6 +707,18 @@ cgfi_exit: return rc; } +/* Simple function to return a 64 bit hash of string. Rarely called */ +static __u64 simple_hashstr(const char *str) +{ + const __u64 hash_mult = 1125899906842597L; /* a big enough prime */ + __u64 hash = 0; + + while (*str) + hash = (hash + (__u64) *str++) * hash_mult; + + return hash; +} + int cifs_get_inode_info(struct inode **inode, const char *full_path, FILE_ALL_INFO *data, struct super_block *sb, int xid, @@ -816,6 +828,14 @@ cifs_get_inode_info(struct inode **inode, const char *full_path, tmprc); fattr.cf_uniqueid = iunique(sb, ROOT_I); cifs_autodisable_serverino(cifs_sb); + } else if ((fattr.cf_uniqueid == 0) && + strlen(full_path) == 0) { + /* some servers ret bad root ino ie 0 */ + cifs_dbg(FYI, "Invalid (0) inodenum\n"); + fattr.cf_flags |= + CIFS_FATTR_FAKE_ROOT_INO; + fattr.cf_uniqueid = + simple_hashstr(tcon->treeName); } } } else @@ -832,6 +852,16 @@ cifs_get_inode_info(struct inode **inode, const char *full_path, &fattr.cf_uniqueid, data); if (tmprc) fattr.cf_uniqueid = CIFS_I(*inode)->uniqueid; + else if ((fattr.cf_uniqueid == 0) && + strlen(full_path) == 0) { + /* + * Reuse existing root inode num since + * inum zero for root causes ls of . and .. to + * not be returned + */ + cifs_dbg(FYI, "Srv ret 0 inode num for root\n"); + fattr.cf_uniqueid = CIFS_I(*inode)->uniqueid; + } } else fattr.cf_uniqueid = CIFS_I(*inode)->uniqueid; } @@ -893,6 +923,9 @@ cifs_get_inode_info(struct inode **inode, const char *full_path, } cgii_exit: + if ((*inode) && ((*inode)->i_ino == 0)) + cifs_dbg(FYI, "inode number of zero returned\n"); + kfree(buf); cifs_put_tlink(tlink); return rc; -- cgit v1.2.1