From 1b5f2928cc6be8fe2d4ca33e3901d09aefcb0d57 Mon Sep 17 00:00:00 2001 From: Steve French Date: Sun, 28 Apr 2024 01:32:09 -0500 Subject: [PATCH] cifs: update the same create_guid on replay [ Upstream commit 79520587fe42cd4988aff8695d60621e689109cb ] File open requests made to the server contain a CreateGuid, which is used by the server to identify the open request. If the same request needs to be replayed, it needs to be sent with the same CreateGuid in the durable handle v2 context. Without doing so, we could end up leaking handles on the server when: 1. multichannel is used AND 2. connection goes down, but not for all channels This is because the replayed open request would have a new CreateGuid and the server will treat this as a new request and open a new handle. This change fixes this by reusing the existing create_guid stored in the cached fid struct. REF: MS-SMB2 4.9 Replay Create Request on an Alternate Channel Fixes: 4f1fffa23769 ("cifs: commands that are retried should have replay flag set") Signed-off-by: Shyam Prasad N Signed-off-by: Steve French Signed-off-by: Sasha Levin --- fs/smb/client/cached_dir.c | 1 + fs/smb/client/cifsglob.h | 1 + fs/smb/client/smb2ops.c | 4 ++++ fs/smb/client/smb2pdu.c | 10 ++++++++-- 4 files changed, 14 insertions(+), 2 deletions(-) diff --git a/fs/smb/client/cached_dir.c b/fs/smb/client/cached_dir.c index ca0fd25236ef..0ff2491c311d 100644 --- a/fs/smb/client/cached_dir.c +++ b/fs/smb/client/cached_dir.c @@ -243,6 +243,7 @@ replay_again: FILE_READ_EA, .disposition = FILE_OPEN, .fid = pfid, + .replay = !!(retries), }; rc = SMB2_open_init(tcon, server, diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h index 8fbdb781d70a..181e9d5b10f9 100644 --- a/fs/smb/client/cifsglob.h +++ b/fs/smb/client/cifsglob.h @@ -1382,6 +1382,7 @@ struct cifs_open_parms { struct cifs_fid *fid; umode_t mode; bool reconnect:1; + bool replay:1; /* indicates that this open is for a replay */ }; struct cifs_fid { diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c index 06735c5685bf..23cf6e92fd54 100644 --- a/fs/smb/client/smb2ops.c +++ b/fs/smb/client/smb2ops.c @@ -1204,6 +1204,7 @@ replay_again: .disposition = FILE_OPEN, .create_options = cifs_create_options(cifs_sb, 0), .fid = &fid, + .replay = !!(retries), }; rc = SMB2_open_init(tcon, server, @@ -1570,6 +1571,7 @@ replay_again: .disposition = FILE_OPEN, .create_options = cifs_create_options(cifs_sb, create_options), .fid = &fid, + .replay = !!(retries), }; if (qi.flags & PASSTHRU_FSCTL) { @@ -2296,6 +2298,7 @@ replay_again: .disposition = FILE_OPEN, .create_options = cifs_create_options(cifs_sb, 0), .fid = fid, + .replay = !!(retries), }; rc = SMB2_open_init(tcon, server, @@ -2684,6 +2687,7 @@ replay_again: .disposition = FILE_OPEN, .create_options = cifs_create_options(cifs_sb, 0), .fid = &fid, + .replay = !!(retries), }; rc = SMB2_open_init(tcon, server, diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c index c73a621a8b83..60793143e24c 100644 --- a/fs/smb/client/smb2pdu.c +++ b/fs/smb/client/smb2pdu.c @@ -2421,8 +2421,13 @@ create_durable_v2_buf(struct cifs_open_parms *oparms) */ buf->dcontext.Timeout = cpu_to_le32(oparms->tcon->handle_timeout); buf->dcontext.Flags = cpu_to_le32(SMB2_DHANDLE_FLAG_PERSISTENT); - generate_random_uuid(buf->dcontext.CreateGuid); - memcpy(pfid->create_guid, buf->dcontext.CreateGuid, 16); + + /* for replay, we should not overwrite the existing create guid */ + if (!oparms->replay) { + generate_random_uuid(buf->dcontext.CreateGuid); + memcpy(pfid->create_guid, buf->dcontext.CreateGuid, 16); + } else + memcpy(buf->dcontext.CreateGuid, pfid->create_guid, 16); /* SMB2_CREATE_DURABLE_HANDLE_REQUEST is "DH2Q" */ buf->Name[0] = 'D'; @@ -3159,6 +3164,7 @@ replay_again: /* reinitialize for possible replay */ flags = 0; server = cifs_pick_channel(ses); + oparms->replay = !!(retries); cifs_dbg(FYI, "create/open\n"); if (!ses || !server) -- 2.34.1