From ff93aba3e671bbde7d46a9b6e6af1136142e31e5 Mon Sep 17 00:00:00 2001 From: Steve French Date: Tue, 8 Oct 2019 00:27:14 -0500 Subject: [PATCH 1/3] smb3: Fix regression in time handling Fixes: cb7a69e60590 ("cifs: Initialize filesystem timestamp ranges") Only very old servers (e.g. OS/2 and DOS) did not support DCE TIME (100 nanosecond granularity). Fix the checks used to set minimum and maximum times. CC: Deepa Dinamani Acked-by: Jeff Layton Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky --- fs/cifs/cifsfs.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 2e9c7f493f99..45330b32f1bb 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -169,18 +169,26 @@ cifs_read_super(struct super_block *sb) else sb->s_maxbytes = MAX_NON_LFS; - /* BB FIXME fix time_gran to be larger for LANMAN sessions */ - sb->s_time_gran = 100; - - if (tcon->unix_ext) { - ts = cifs_NTtimeToUnix(0); + /* Some very old servers like DOS and OS/2 used 2 second granularity */ + if ((tcon->ses->server->vals->protocol_id == SMB10_PROT_ID) && + ((tcon->ses->capabilities & + tcon->ses->server->vals->cap_nt_find) == 0) && + !tcon->unix_ext) { + sb->s_time_gran = 2000000000; /* 2 seconds */ + ts = cnvrtDosUnixTm(cpu_to_le16(SMB_DATE_MIN), 0, 0); sb->s_time_min = ts.tv_sec; - ts = cifs_NTtimeToUnix(cpu_to_le64(S64_MAX)); + ts = cnvrtDosUnixTm(cpu_to_le16(SMB_DATE_MAX), + cpu_to_le16(SMB_TIME_MAX), 0); sb->s_time_max = ts.tv_sec; } else { - ts = cnvrtDosUnixTm(cpu_to_le16(SMB_DATE_MIN), 0, 0); + /* + * Almost every server, including all SMB2+, uses DCE TIME + * ie 100 nanosecond units, since 1601. See MS-DTYP and MS-FSCC + */ + sb->s_time_gran = 100; + ts = cifs_NTtimeToUnix(0); sb->s_time_min = ts.tv_sec; - ts = cnvrtDosUnixTm(cpu_to_le16(SMB_DATE_MAX), cpu_to_le16(SMB_TIME_MAX), 0); + ts = cifs_NTtimeToUnix(cpu_to_le64(S64_MAX)); sb->s_time_max = ts.tv_sec; } -- 2.20.1