4.18-stable review patch. If anyone has any objections, please let me know.
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From: Steve French stfrench@microsoft.com
[ Upstream commit 8505c8bfd85a260c9dc5c47e15bd8c5357fcbcd2 ]
If user specifies "posix" on an SMB3.11 mount, then fail the mount if server does not return the POSIX negotiate context indicating support for posix.
Signed-off-by: Steve French stfrench@microsoft.com Reviewed-by: Aurelien Aptel aaptel@suse.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/cifs/connect.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
--- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -3031,11 +3031,15 @@ cifs_get_tcon(struct cifs_ses *ses, stru }
#ifdef CONFIG_CIFS_SMB311 - if ((volume_info->linux_ext) && (ses->server->posix_ext_supported)) { - if (ses->server->vals->protocol_id == SMB311_PROT_ID) { + if (volume_info->linux_ext) { + if (ses->server->posix_ext_supported) { tcon->posix_extensions = true; printk_once(KERN_WARNING "SMB3.11 POSIX Extensions are experimental\n"); + } else { + cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions.\n"); + rc = -EOPNOTSUPP; + goto out_fail; } } #endif /* 311 */