> Subject: RE: [Patch v2 2/6] cifs: Allocate validate negotiation request through > kmalloc > > > > > -----Original Message----- > > From: linux-rdma-owner@xxxxxxxxxxxxxxx [mailto:linux-rdma- > > owner@xxxxxxxxxxxxxxx] On Behalf Of Long Li > > Sent: Tuesday, April 17, 2018 2:17 PM > > To: Steve French <sfrench@xxxxxxxxx>; linux-cifs@xxxxxxxxxxxxxxx; > > samba- technical@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux- > > rdma@xxxxxxxxxxxxxxx > > Cc: longli <longli@xxxxxxxxxxxxx>; stable@xxxxxxxxxxxxxxx > > Subject: [Patch v2 2/6] cifs: Allocate validate negotiation request > > through kmalloc > > > > From: Long Li <longli@xxxxxxxxxxxxx> > > > > The data buffer allocated on the stack can't be DMA'ed, and hence > > can't send through RDMA via SMB Direct. > > > > Fix this by allocating the request on the heap in smb3_validate_negotiate. > > > > Fixes: ff1c038addc4f205d5f1ede449426c7d316c0eed "Check SMB3 dialects > > against downgrade attacks" > > > > Format is: > Fixes: ff1c038addc4 ("Check SMB3 dialects against downgrade attacks") It > should be right above Signed-off signature. I will fix up and resend this patch. How about the rest patches (1, 3-6) in the series? If they don't need any changes, is it okay that I resend this one only? > > > Changes in v2: > > Removed duplicated code on freeing buffers on function exit. > > (Thanks to Parav Pandit <parav@xxxxxxxxxxxx>) > > > > Fixed typo in the patch title. > > > > Signed-off-by: Long Li <longli@xxxxxxxxxxxxx> > > Cc: stable@xxxxxxxxxxxxxxx > > --- > > fs/cifs/smb2pdu.c | 57 > > ++++++++++++++++++++++++++++++------------------------ > > - > > 1 file changed, 31 insertions(+), 26 deletions(-) > > > > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index > > 0f044c4..41625e4 > > 100644 > > --- a/fs/cifs/smb2pdu.c > > +++ b/fs/cifs/smb2pdu.c > > @@ -729,8 +729,8 @@ SMB2_negotiate(const unsigned int xid, struct > > cifs_ses > > *ses) > > > > int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon) > { > > - int rc = 0; > > - struct validate_negotiate_info_req vneg_inbuf; > > + int ret, rc = -EIO; > > + struct validate_negotiate_info_req *pneg_inbuf; > > struct validate_negotiate_info_rsp *pneg_rsp = NULL; > > u32 rsplen; > > u32 inbuflen; /* max of 4 dialects */ @@ -741,6 +741,9 @@ int > > smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon > > *tcon) > > if (tcon->ses->server->rdma) > > return 0; > > #endif > > + pneg_inbuf = kmalloc(sizeof(*pneg_inbuf), GFP_KERNEL); > > + if (!pneg_inbuf) > > + return -ENOMEM; > > > > /* In SMB3.11 preauth integrity supersedes validate negotiate */ > > if (tcon->ses->server->dialect == SMB311_PROT_ID) @@ -764,53 > > +767,53 @@ int smb3_validate_negotiate(const unsigned int xid, struct > > cifs_tcon *tcon) > > if (tcon->ses->session_flags & SMB2_SESSION_FLAG_IS_NULL) > > cifs_dbg(VFS, "Unexpected null user (anonymous) auth flag > sent by > > server\n"); > > > > - vneg_inbuf.Capabilities = > > + pneg_inbuf->Capabilities = > > cpu_to_le32(tcon->ses->server->vals- > > >req_capabilities); > > - memcpy(vneg_inbuf.Guid, tcon->ses->server->client_guid, > > + memcpy(pneg_inbuf->Guid, tcon->ses->server->client_guid, > > SMB2_CLIENT_GUID_SIZE); > > > > if (tcon->ses->sign) > > - vneg_inbuf.SecurityMode = > > + pneg_inbuf->SecurityMode = > > > cpu_to_le16(SMB2_NEGOTIATE_SIGNING_REQUIRED); > > else if (global_secflags & CIFSSEC_MAY_SIGN) > > - vneg_inbuf.SecurityMode = > > + pneg_inbuf->SecurityMode = > > > cpu_to_le16(SMB2_NEGOTIATE_SIGNING_ENABLED); > > else > > - vneg_inbuf.SecurityMode = 0; > > + pneg_inbuf->SecurityMode = 0; > > > > > > if (strcmp(tcon->ses->server->vals->version_string, > Please check if strncmp() should be used or not. > > > SMB3ANY_VERSION_STRING) == 0) { > > - vneg_inbuf.Dialects[0] = cpu_to_le16(SMB30_PROT_ID); > > - vneg_inbuf.Dialects[1] = cpu_to_le16(SMB302_PROT_ID); > > - vneg_inbuf.DialectCount = cpu_to_le16(2); > > + pneg_inbuf->Dialects[0] = cpu_to_le16(SMB30_PROT_ID); > > + pneg_inbuf->Dialects[1] = cpu_to_le16(SMB302_PROT_ID); > > + pneg_inbuf->DialectCount = cpu_to_le16(2); > > /* structure is big enough for 3 dialects, sending only 2 */ > > inbuflen = sizeof(struct validate_negotiate_info_req) - 2; > > } else if (strcmp(tcon->ses->server->vals->version_string, > > SMBDEFAULT_VERSION_STRING) == 0) { > > - vneg_inbuf.Dialects[0] = cpu_to_le16(SMB21_PROT_ID); > > - vneg_inbuf.Dialects[1] = cpu_to_le16(SMB30_PROT_ID); > > - vneg_inbuf.Dialects[2] = cpu_to_le16(SMB302_PROT_ID); > > - vneg_inbuf.DialectCount = cpu_to_le16(3); > > + pneg_inbuf->Dialects[0] = cpu_to_le16(SMB21_PROT_ID); > > + pneg_inbuf->Dialects[1] = cpu_to_le16(SMB30_PROT_ID); > > + pneg_inbuf->Dialects[2] = cpu_to_le16(SMB302_PROT_ID); > > + pneg_inbuf->DialectCount = cpu_to_le16(3); > > /* structure is big enough for 3 dialects */ > > inbuflen = sizeof(struct validate_negotiate_info_req); > > } else { > > /* otherwise specific dialect was requested */ > > - vneg_inbuf.Dialects[0] = > > + pneg_inbuf->Dialects[0] = > > cpu_to_le16(tcon->ses->server->vals->protocol_id); > > - vneg_inbuf.DialectCount = cpu_to_le16(1); > > + pneg_inbuf->DialectCount = cpu_to_le16(1); > > /* structure is big enough for 3 dialects, sending only 1 */ > > inbuflen = sizeof(struct validate_negotiate_info_req) - 4; > > } > > > > - rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID, > > + ret = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID, > > FSCTL_VALIDATE_NEGOTIATE_INFO, true /* is_fsctl */, > > - (char *)&vneg_inbuf, sizeof(struct > > validate_negotiate_info_req), > > + (char *)pneg_inbuf, sizeof(struct > validate_negotiate_info_req), > > Use sizeof(*pneg_inbuf) > > > (char **)&pneg_rsp, &rsplen); > > > > - if (rc != 0) { > > - cifs_dbg(VFS, "validate protocol negotiate failed: %d\n", rc); > > - return -EIO; > > + if (ret != 0) { > > if (ret) is fine. > > > + cifs_dbg(VFS, "validate protocol negotiate failed: %d\n", ret); > > + goto out_free_inbuf; > > } > > > > if (rsplen != sizeof(struct validate_negotiate_info_rsp)) { @@ > > -820,7 > > if (rsplen != sizeof(*pneg_rsp))