1 files changed, 120 insertions, 58 deletions

diff --git a/drivers/usb/host/uhci-debug.c b/drivers/usb/host/uhci-debug.c
index fc0b0daac93d..455737546525 100644
--- a/drivers/usb/host/uhci-debug.c
+++ b/drivers/usb/host/uhci-debug.c
@@ -16,6 +16,8 @@
 
 #include "uhci-hcd.h"
 
+#define EXTRA_SPACE     1024
+
 static struct dentry *uhci_debugfs_root;
 
 #ifdef DEBUG
@@ -44,10 +46,6 @@ static int uhci_show_td(struct uhci_hcd *uhci, struct uhci_td *td, char *buf,
         char *spid;
         u32 status, token;
 
-        /* Try to make sure there's enough memory */
-        if (len < 160)
-                return 0;
-
         status = td_status(uhci, td);
         out += sprintf(out, "%*s[%p] link (%08x) ", space, "", td,
                 hc32_to_cpu(uhci, td->link));
@@ -64,6 +62,8 @@ static int uhci_show_td(struct uhci_hcd *uhci, struct uhci_td *td, char *buf,
                 (status & TD_CTRL_CRCTIMEO) ? "CRC/Timeo " : "",
                 (status & TD_CTRL_BITSTUFF) ? "BitStuff " : "",
                 status & 0x7ff);
+        if (out - buf > len)
+                goto done;
 
         token = td_token(uhci, td);
         switch (uhci_packetid(token)) {
@@ -90,6 +90,9 @@ static int uhci_show_td(struct uhci_hcd *uhci, struct uhci_td *td, char *buf,
                 spid);
         out += sprintf(out, "(buf=%08x)\n", hc32_to_cpu(uhci, td->buffer));
 
+done:
+        if (out - buf > len)
+                out += sprintf(out, " ...\n");
         return out - buf;
 }
 
@@ -101,8 +104,6 @@ static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp,
         int i, nactive, ninactive;
         char *ptype;
 
-        if (len < 200)
-                return 0;
 
         out += sprintf(out, "urb_priv [%p] ", urbp);
         out += sprintf(out, "urb [%p] ", urbp->urb);
@@ -110,6 +111,8 @@ static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp,
         out += sprintf(out, "Dev=%d ", usb_pipedevice(urbp->urb->pipe));
         out += sprintf(out, "EP=%x(%s) ", usb_pipeendpoint(urbp->urb->pipe),
                         (usb_pipein(urbp->urb->pipe) ? "IN" : "OUT"));
+        if (out - buf > len)
+                goto done;
 
         switch (usb_pipetype(urbp->urb->pipe)) {
         case PIPE_ISOCHRONOUS: ptype = "ISO"; break;
@@ -128,6 +131,9 @@ static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp,
                 out += sprintf(out, " Unlinked=%d", urbp->urb->unlinked);
         out += sprintf(out, "\n");
 
+        if (out - buf > len)
+                goto done;
+
         i = nactive = ninactive = 0;
         list_for_each_entry(td, &urbp->td_list, list) {
                 if (urbp->qh->type != USB_ENDPOINT_XFER_ISOC &&
@@ -135,6 +141,8 @@ static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp,
                         out += sprintf(out, "%*s%d: ", space + 2, "", i);
                         out += uhci_show_td(uhci, td, out,
                                         len - (out - buf), 0);
+                        if (out - buf > len)
+                                goto tail;
                 } else {
                         if (td_status(uhci, td) & TD_CTRL_ACTIVE)
                                 ++nactive;
@@ -143,10 +151,13 @@ static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp,
                 }
         }
         if (nactive + ninactive > 0)
-                out += sprintf(out, "%*s[skipped %d inactive and %d active "
-                                "TDs]\n",
+                out += sprintf(out,
+                                "%*s[skipped %d inactive and %d active TDs]\n",
                                 space, "", ninactive, nactive);
-
+done:
+        if (out - buf > len)
+                out += sprintf(out, " ...\n");
+tail:
         return out - buf;
 }
 
@@ -158,10 +169,6 @@ static int uhci_show_qh(struct uhci_hcd *uhci,
         __hc32 element = qh_element(qh);
         char *qtype;
 
-        /* Try to make sure there's enough memory */
-        if (len < 80 * 7)
-                return 0;
-
         switch (qh->type) {
         case USB_ENDPOINT_XFER_ISOC: qtype = "ISO"; break;
         case USB_ENDPOINT_XFER_INT: qtype = "INT"; break;
@@ -175,13 +182,15 @@ static int uhci_show_qh(struct uhci_hcd *uhci,
                         hc32_to_cpu(uhci, qh->link),
                         hc32_to_cpu(uhci, element));
         if (qh->type == USB_ENDPOINT_XFER_ISOC)
-                out += sprintf(out, "%*s    period %d phase %d load %d us, "
-                                "frame %x desc [%p]\n",
+                out += sprintf(out,
+                                "%*s    period %d phase %d load %d us, frame %x desc [%p]\n",
                                 space, "", qh->period, qh->phase, qh->load,
                                 qh->iso_frame, qh->iso_packet_desc);
         else if (qh->type == USB_ENDPOINT_XFER_INT)
                 out += sprintf(out, "%*s    period %d phase %d load %d us\n",
                                 space, "", qh->period, qh->phase, qh->load);
+        if (out - buf > len)
+                goto done;
 
         if (element & UHCI_PTR_QH(uhci))
                 out += sprintf(out, "%*s  Element points to QH (bug?)\n", space, "");
@@ -195,11 +204,17 @@ static int uhci_show_qh(struct uhci_hcd *uhci,
         if (!(element & ~(UHCI_PTR_QH(uhci) | UHCI_PTR_DEPTH(uhci))))
                 out += sprintf(out, "%*s  Element is NULL (bug?)\n", space, "");
 
+        if (out - buf > len)
+                goto done;
+
         if (list_empty(&qh->queue)) {
                 out += sprintf(out, "%*s  queue is empty\n", space, "");
-                if (qh == uhci->skel_async_qh)
+                if (qh == uhci->skel_async_qh) {
                         out += uhci_show_td(uhci, uhci->term_td, out,
                                         len - (out - buf), 0);
+                        if (out - buf > len)
+                                goto tail;
+                }
         } else {
                 struct urb_priv *urbp = list_entry(qh->queue.next,
                                 struct urb_priv, node);
@@ -211,9 +226,12 @@ static int uhci_show_qh(struct uhci_hcd *uhci,
                                         space, "");
                 i = nurbs = 0;
                 list_for_each_entry(urbp, &qh->queue, node) {
-                        if (++i <= 10)
+                        if (++i <= 10) {
                                 out += uhci_show_urbp(uhci, urbp, out,
                                                 len - (out - buf), space + 2);
+                                if (out - buf > len)
+                                        goto tail;
+                        }
                         else
                                 ++nurbs;
                 }
@@ -222,24 +240,27 @@ static int uhci_show_qh(struct uhci_hcd *uhci,
                                         space, "", nurbs);
         }
 
+        if (out - buf > len)
+                goto done;
+
         if (qh->dummy_td) {
                 out += sprintf(out, "%*s  Dummy TD\n", space, "");
                 out += uhci_show_td(uhci, qh->dummy_td, out,
                                 len - (out - buf), 0);
+                if (out - buf > len)
+                        goto tail;
         }
 
+done:
+        if (out - buf > len)
+                out += sprintf(out, " ...\n");
+tail:
         return out - buf;
 }
 
-static int uhci_show_sc(int port, unsigned short status, char *buf, int len)
+static int uhci_show_sc(int port, unsigned short status, char *buf)
 {
-        char *out = buf;
-
-        /* Try to make sure there's enough memory */
-        if (len < 160)
-                return 0;
-
-        out += sprintf(out, "  stat%d     =     %04x  %s%s%s%s%s%s%s%s%s%s\n",
+        return sprintf(buf, "  stat%d     =     %04x  %s%s%s%s%s%s%s%s%s%s\n",
                 port,
                 status,
                 (status & USBPORTSC_SUSP) ?     " Suspend" : "",
@@ -252,19 +273,12 @@ static int uhci_show_sc(int port, unsigned short status, char *buf, int len)
                 (status & USBPORTSC_PE) ?       " Enabled" : "",
                 (status & USBPORTSC_CSC) ?      " ConnectChange" : "",
                 (status & USBPORTSC_CCS) ?      " Connected" : "");
-
-        return out - buf;
 }
 
-static int uhci_show_root_hub_state(struct uhci_hcd *uhci, char *buf, int len)
+static int uhci_show_root_hub_state(struct uhci_hcd *uhci, char *buf)
 {
-        char *out = buf;
         char *rh_state;
 
-        /* Try to make sure there's enough memory */
-        if (len < 60)
-                return 0;
-
         switch (uhci->rh_state) {
             case UHCI_RH_RESET:
                 rh_state = "reset";             break;
@@ -283,9 +297,8 @@ static int uhci_show_root_hub_state(struct uhci_hcd *uhci, char *buf, int len)
             default:
                 rh_state = "?";                 break;
         }
-        out += sprintf(out, "Root-hub state: %s   FSBR: %d\n",
+        return sprintf(buf, "Root-hub state: %s   FSBR: %d\n",
                         rh_state, uhci->fsbr_is_on);
-        return out - buf;
 }
 
 static int uhci_show_status(struct uhci_hcd *uhci, char *buf, int len)
@@ -296,9 +309,6 @@ static int uhci_show_status(struct uhci_hcd *uhci, char *buf, int len)
         unsigned char sof;
         unsigned short portsc1, portsc2;
 
-        /* Try to make sure there's enough memory */
-        if (len < 80 * 9)
-                return 0;
 
         usbcmd    = uhci_readw(uhci, 0);
         usbstat   = uhci_readw(uhci, 2);
@@ -319,6 +329,8 @@ static int uhci_show_status(struct uhci_hcd *uhci, char *buf, int len)
                 (usbcmd & USBCMD_GRESET) ?  "GRESET " : "",
                 (usbcmd & USBCMD_HCRESET) ? "HCRESET " : "",
                 (usbcmd & USBCMD_RS) ?      "RS " : "");
+        if (out - buf > len)
+                goto done;
 
         out += sprintf(out, "  usbstat   =     %04x   %s%s%s%s%s%s\n",
                 usbstat,
@@ -328,19 +340,33 @@ static int uhci_show_status(struct uhci_hcd *uhci, char *buf, int len)
                 (usbstat & USBSTS_RD) ?     "ResumeDetect " : "",
                 (usbstat & USBSTS_ERROR) ?  "USBError " : "",
                 (usbstat & USBSTS_USBINT) ? "USBINT " : "");
+        if (out - buf > len)
+                goto done;
 
         out += sprintf(out, "  usbint    =     %04x\n", usbint);
         out += sprintf(out, "  usbfrnum  =   (%d)%03x\n", (usbfrnum >> 10) & 1,
                 0xfff & (4*(unsigned int)usbfrnum));
         out += sprintf(out, "  flbaseadd = %08x\n", flbaseadd);
         out += sprintf(out, "  sof       =       %02x\n", sof);
-        out += uhci_show_sc(1, portsc1, out, len - (out - buf));
-        out += uhci_show_sc(2, portsc2, out, len - (out - buf));
-        out += sprintf(out, "Most recent frame: %x (%d)   "
-                        "Last ISO frame: %x (%d)\n",
+        if (out - buf > len)
+                goto done;
+
+        out += uhci_show_sc(1, portsc1, out);
+        if (out - buf > len)
+                goto done;
+
+        out += uhci_show_sc(2, portsc2, out);
+        if (out - buf > len)
+                goto done;
+
+        out += sprintf(out,
+                        "Most recent frame: %x (%d)   Last ISO frame: %x (%d)\n",
                         uhci->frame_number, uhci->frame_number & 1023,
                         uhci->last_iso_frame, uhci->last_iso_frame & 1023);
 
+done:
+        if (out - buf > len)
+                out += sprintf(out, " ...\n");
         return out - buf;
 }
 
@@ -360,9 +386,13 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
                 "int8", "int4", "int2", "async", "term"
         };
 
-        out += uhci_show_root_hub_state(uhci, out, len - (out - buf));
+        out += uhci_show_root_hub_state(uhci, out);
+        if (out - buf > len)
+                goto done;
         out += sprintf(out, "HC status\n");
         out += uhci_show_status(uhci, out, len - (out - buf));
+        if (out - buf > len)
+                goto tail;
 
         out += sprintf(out, "Periodic load table\n");
         for (i = 0; i < MAX_PHASE; ++i) {
@@ -375,7 +405,7 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
                         uhci_to_hcd(uhci)->self.bandwidth_int_reqs,
                         uhci_to_hcd(uhci)->self.bandwidth_isoc_reqs);
         if (debug <= 1)
-                return out - buf;
+                goto tail;
 
         out += sprintf(out, "Frame List\n");
         nframes = 10;
@@ -383,6 +413,8 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
         for (i = 0; i < UHCI_NUMFRAMES; ++i) {
                 __hc32 qh_dma;
 
+                if (out - buf > len)
+                        goto done;
                 j = 0;
                 td = uhci->frame_cpu[i];
                 link = uhci->frame[i];
@@ -401,15 +433,20 @@ static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
                         td = list_entry(tmp, struct uhci_td, fl_list);
                         tmp = tmp->next;
                         if (link != LINK_TO_TD(uhci, td)) {
-                                if (nframes > 0)
-                                        out += sprintf(out, "    link does "
-                                                "not match list entry!\n");
-                                else
+                                if (nframes > 0) {
+                                        out += sprintf(out,
+                                                "    link does not match list entry!\n");
+                                        if (out - buf > len)
+                                                goto done;
+                                } else
                                         ++nerrs;
                         }
-                        if (nframes > 0)
+                        if (nframes > 0) {
                                 out += uhci_show_td(uhci, td, out,
                                                 len - (out - buf), 4);
+                                if (out - buf > len)
+                                        goto tail;
+                        }
                         link = td->link;
                 } while (tmp != head);
 
@@ -423,9 +460,11 @@ check_link:
                                                 i, hc32_to_cpu(uhci, link));
                                         j = 1;
                                 }
-                                out += sprintf(out, "   link does not match "
-                                        "QH (%08x)!\n",
+                                out += sprintf(out,
+                                        "   link does not match QH (%08x)!\n",
                                         hc32_to_cpu(uhci, qh_dma));
+                                if (out - buf > len)
+                                        goto done;
                         } else
                                 ++nerrs;
                 }
@@ -436,18 +475,27 @@ check_link:
 
         out += sprintf(out, "Skeleton QHs\n");
 
+        if (out - buf > len)
+                goto done;
+
         fsbr_link = 0;
         for (i = 0; i < UHCI_NUM_SKELQH; ++i) {
                 int cnt = 0;
 
                 qh = uhci->skelqh[i];
-                out += sprintf(out, "- skel_%s_qh\n", qh_names[i]); \
+                out += sprintf(out, "- skel_%s_qh\n", qh_names[i]);
                 out += uhci_show_qh(uhci, qh, out, len - (out - buf), 4);
+                if (out - buf > len)
+                        goto tail;
 
                 /* Last QH is the Terminating QH, it's different */
                 if (i == SKEL_TERM) {
-                        if (qh_element(qh) != LINK_TO_TD(uhci, uhci->term_td))
-                                out += sprintf(out, "    skel_term_qh element is not set to term_td!\n");
+                        if (qh_element(qh) != LINK_TO_TD(uhci, uhci->term_td)) {
+                                out += sprintf(out,
+                                        "    skel_term_qh element is not set to term_td!\n");
+                                if (out - buf > len)
+                                        goto done;
+                        }
                         link = fsbr_link;
                         if (!link)
                                 link = LINK_TO_QH(uhci, uhci->skel_term_qh);
@@ -460,9 +508,12 @@ check_link:
                 while (tmp != head) {
                         qh = list_entry(tmp, struct uhci_qh, node);
                         tmp = tmp->next;
-                        if (++cnt <= 10)
+                        if (++cnt <= 10) {
                                 out += uhci_show_qh(uhci, qh, out,
                                                 len - (out - buf), 4);
+                                if (out - buf > len)
+                                        goto tail;
+                        }
                         if (!fsbr_link && qh->skel >= SKEL_FSBR)
                                 fsbr_link = LINK_TO_QH(uhci, qh);
                 }
@@ -480,9 +531,17 @@ check_link:
                         link = LINK_TO_QH(uhci, uhci->skel_term_qh);
 check_qh_link:
                 if (qh->link != link)
-                        out += sprintf(out, "    last QH not linked to next skeleton!\n");
+                        out += sprintf(out,
+                                "    last QH not linked to next skeleton!\n");
+
+                if (out - buf > len)
+                        goto done;
         }
 
+done:
+        if (out - buf > len)
+                out += sprintf(out, " ...\n");
+tail:
         return out - buf;
 }
 
@@ -514,7 +573,8 @@ static int uhci_debug_open(struct inode *inode, struct file *file)
         up->size = 0;
         spin_lock_irqsave(&uhci->lock, flags);
         if (uhci->is_initialized)
-                up->size = uhci_sprint_schedule(uhci, up->data, MAX_OUTPUT);
+                up->size = uhci_sprint_schedule(uhci, up->data,
+                                        MAX_OUTPUT - EXTRA_SPACE);
         spin_unlock_irqrestore(&uhci->lock, flags);
 
         file->private_data = up;
@@ -529,7 +589,9 @@ static loff_t uhci_debug_lseek(struct file *file, loff_t off, int whence)
 
         up = file->private_data;
 
-        /* XXX: atomic 64bit seek access, but that needs to be fixed in the VFS */
+        /*
+         * XXX: atomic 64bit seek access, but that needs to be fixed in the VFS
+         */
         switch (whence) {
         case 0:
                 new = off;