4.20-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit 6a9cbdd1ceca1dc2359ddf082efe61b97c3e752b ]
If the server doesn't grant us at least 3 credits during the mount we won't be able to complete it because query path info operation requires 3 credits. Use the cached file handle if possible to allow the mount to succeed.
Signed-off-by: Pavel Shilovsky pshilov@microsoft.com Reviewed-by: Ronnie Sahlberg lsahlber@redhat.com Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/cifs/smb2inode.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)
diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c index a8999f930b22..057d2034209f 100644 --- a/fs/cifs/smb2inode.c +++ b/fs/cifs/smb2inode.c @@ -294,6 +294,8 @@ smb2_query_path_info(const unsigned int xid, struct cifs_tcon *tcon, int rc; struct smb2_file_all_info *smb2_data; __u32 create_options = 0; + struct cifs_fid fid; + bool no_cached_open = tcon->nohandlecache;
*adjust_tz = false; *symlink = false; @@ -302,6 +304,21 @@ smb2_query_path_info(const unsigned int xid, struct cifs_tcon *tcon, GFP_KERNEL); if (smb2_data == NULL) return -ENOMEM; + + /* If it is a root and its handle is cached then use it */ + if (!strlen(full_path) && !no_cached_open) { + rc = open_shroot(xid, tcon, &fid); + if (rc) + goto out; + rc = SMB2_query_info(xid, tcon, fid.persistent_fid, + fid.volatile_fid, smb2_data); + close_shroot(&tcon->crfid); + if (rc) + goto out; + move_smb2_info_to_cifs(data, smb2_data); + goto out; + } + if (backup_cred(cifs_sb)) create_options |= CREATE_OPEN_BACKUP_INTENT;