> -----Original Message----- > From: linux-rdma-owner@xxxxxxxxxxxxxxx [mailto:linux-rdma- > owner@xxxxxxxxxxxxxxx] On Behalf Of Long Li > Sent: Monday, April 16, 2018 7:49 PM > To: Steve French <sfrench@xxxxxxxxx>; linux-cifs@xxxxxxxxxxxxxxx; samba- > technical@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux- > rdma@xxxxxxxxxxxxxxx; stable@xxxxxxxxxxxxxxx > Cc: longli <longli@xxxxxxxxxxxxx> > Subject: [PATCH 2/6] cifs: Allocate validate negoation 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. > Please provide Fixes ("12-letters commit id") "commit string" which introduced this issue and it is getting fixed here, so that other can apply this fix to older versions. > Signed-off-by: Long Li <longli@xxxxxxxxxxxxx> > --- > fs/cifs/smb2pdu.c | 38 ++++++++++++++++++++++---------------- > 1 file changed, 22 insertions(+), 16 deletions(-) > > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 0f044c4..abbefe2 > 100644 > --- a/fs/cifs/smb2pdu.c > +++ b/fs/cifs/smb2pdu.c > @@ -730,7 +730,7 @@ 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; > + struct validate_negotiate_info_req *pneg_inbuf; [..] > rc = 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), > (char **)&pneg_rsp, &rsplen); > > if (rc != 0) { > cifs_dbg(VFS, "validate protocol negotiate failed: %d\n", rc); > + kfree(pneg_inbuf); > return -EIO; Instead of duplicating code here, please jump to err_rsp_free label. Kfree() takes care to not panic for NULL pointer. Or for clarity define new label. > } > > @@ -838,12 +842,14 @@ int smb3_validate_negotiate(const unsigned int xid, > struct cifs_tcon *tcon) > > /* validate negotiate successful */ > cifs_dbg(FYI, "validate negotiate info successful\n"); > + kfree(pneg_inbuf); > kfree(pneg_rsp); > return 0; > > vneg_out: > cifs_dbg(VFS, "protocol revalidation - security settings mismatch\n"); > err_rsp_free: > + kfree(pneg_inbuf); > kfree(pneg_rsp); > return -EIO; > } > -- > 2.7.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body > of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at > http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
