FAILED: patch "[PATCH] xhci: fix even more unsafe memory usage in xhci tracing" failed to apply to 4.9-stable tree

PATCH [email protected] 1 participant 1 message Sep 10, 2021

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Stable branch USB USB xHCI driver

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2021-09-10 07:10 UTC #0 lore raw

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 4843b4b5ec64b875a5e334f280508f1f75e7d3e4 Mon Sep 17 00:00:00 2001
From: Mathias Nyman <[email protected]>
Date: Fri, 20 Aug 2021 15:34:59 +0300
Subject: [PATCH] xhci: fix even more unsafe memory usage in xhci tracing

Removes static char buffer usage in the following decode functions:
xhci_decode_ctrl_ctx() xhci_decode_slot_context()
xhci_decode_usbsts()
xhci_decode_doorbell()
xhci_decode_ep_context()

Caller must provide a buffer to use.
In tracing use __get_str() as recommended to pass buffer.

Minor changes are needed in other xhci code as these functions are also used elsewhere

Cc <[email protected]>

Signed-off-by Mathias Nyman <[email protected]>

Link https://lore.kernel.org/r/[email protected] open here

Signed-off-by Greg Kroah-Hartman <[email protected]>

drivers/usb/host/xhci-debugfs.c +6 -2

index 85c12f56b17c..dc832ddf7033 100644
@@ -261,11 +261,13 @@ static int xhci_slot_context_show(struct seq_file *s, void *unused)
 	struct xhci_slot_ctx	*slot_ctx;
 	struct xhci_slot_priv	*priv = s->private;
 	struct xhci_virt_device	*dev = priv->dev;
+	char			str[XHCI_MSG_MAX];
 
 	xhci = hcd_to_xhci(bus_to_hcd(dev->udev->bus));
 	slot_ctx = xhci_get_slot_ctx(xhci, dev->out_ctx);
 	seq_printf(s, "%pad: %s\n", &dev->out_ctx->dma,
-		   xhci_decode_slot_context(le32_to_cpu(slot_ctx->dev_info),
+		   xhci_decode_slot_context(str,
+					    le32_to_cpu(slot_ctx->dev_info),
 					    le32_to_cpu(slot_ctx->dev_info2),
 					    le32_to_cpu(slot_ctx->tt_info),
 					    le32_to_cpu(slot_ctx->dev_state)));

@@ -281,6 +283,7 @@ static int xhci_endpoint_context_show(struct seq_file *s, void *unused)
 	struct xhci_ep_ctx	*ep_ctx;
 	struct xhci_slot_priv	*priv = s->private;
 	struct xhci_virt_device	*dev = priv->dev;
+	char			str[XHCI_MSG_MAX];
 
 	xhci = hcd_to_xhci(bus_to_hcd(dev->udev->bus));

@@ -288,7 +291,8 @@ static int xhci_endpoint_context_show(struct seq_file *s, void *unused)
 		ep_ctx = xhci_get_ep_ctx(xhci, dev->out_ctx, ep_index);
 		dma = dev->out_ctx->dma + (ep_index + 1) * CTX_SIZE(xhci->hcc_params);
 		seq_printf(s, "%pad: %s\n", &dma,
-			   xhci_decode_ep_context(le32_to_cpu(ep_ctx->ep_info),
+			   xhci_decode_ep_context(str,
+						  le32_to_cpu(ep_ctx->ep_info),
 						  le32_to_cpu(ep_ctx->ep_info2),
 						  le64_to_cpu(ep_ctx->deq),
 						  le32_to_cpu(ep_ctx->tx_info)));

drivers/usb/host/xhci-ring.c +2 -1

index 8fea44bbc266..d0faa67a689d 100644
@@ -1212,6 +1212,7 @@ void xhci_stop_endpoint_command_watchdog(struct timer_list *t)
 	struct xhci_hcd *xhci = ep->xhci;
 	unsigned long flags;
 	u32 usbsts;
+	char str[XHCI_MSG_MAX];
 
 	spin_lock_irqsave(&xhci->lock, flags);

@@ -1225,7 +1226,7 @@ void xhci_stop_endpoint_command_watchdog(struct timer_list *t)
 	usbsts = readl(&xhci->op_regs->status);
 
 	xhci_warn(xhci, "xHCI host not responding to stop endpoint command.\n");
-	xhci_warn(xhci, "USBSTS:%s\n", xhci_decode_usbsts(usbsts));
+	xhci_warn(xhci, "USBSTS:%s\n", xhci_decode_usbsts(str, usbsts));
 
 	ep->ep_state &= ~EP_STOP_CMD_PENDING;

drivers/usb/host/xhci-trace.h +11 -7

index 5e1c50cb7016..a5da02077297 100644
@@ -322,6 +322,7 @@ DECLARE_EVENT_CLASS(xhci_log_ep_ctx,
 		__field(u32, info2)
 		__field(u64, deq)
 		__field(u32, tx_info)
+		__dynamic_array(char, str, XHCI_MSG_MAX)
 	),
 	TP_fast_assign(
 		__entry->info = le32_to_cpu(ctx->ep_info);

@@ -329,8 +330,8 @@ DECLARE_EVENT_CLASS(xhci_log_ep_ctx,
 		__entry->deq = le64_to_cpu(ctx->deq);
 		__entry->tx_info = le32_to_cpu(ctx->tx_info);
 	),
-	TP_printk("%s", xhci_decode_ep_context(__entry->info,
-		__entry->info2, __entry->deq, __entry->tx_info)
+	TP_printk("%s", xhci_decode_ep_context(__get_str(str),
+		__entry->info, __entry->info2, __entry->deq, __entry->tx_info)
 	)
 );

@@ -367,6 +368,7 @@ DECLARE_EVENT_CLASS(xhci_log_slot_ctx,
 		__field(u32, info2)
 		__field(u32, tt_info)
 		__field(u32, state)
+		__dynamic_array(char, str, XHCI_MSG_MAX)
 	),
 	TP_fast_assign(
 		__entry->info = le32_to_cpu(ctx->dev_info);

@@ -374,9 +376,9 @@ DECLARE_EVENT_CLASS(xhci_log_slot_ctx,
 		__entry->tt_info = le64_to_cpu(ctx->tt_info);
 		__entry->state = le32_to_cpu(ctx->dev_state);
 	),
-	TP_printk("%s", xhci_decode_slot_context(__entry->info,
-			__entry->info2, __entry->tt_info,
-			__entry->state)
+	TP_printk("%s", xhci_decode_slot_context(__get_str(str),
+			__entry->info, __entry->info2,
+			__entry->tt_info, __entry->state)
 	)
 );

@@ -431,12 +433,13 @@ DECLARE_EVENT_CLASS(xhci_log_ctrl_ctx,
 	TP_STRUCT__entry(
 		__field(u32, drop)
 		__field(u32, add)
+		__dynamic_array(char, str, XHCI_MSG_MAX)
 	),
 	TP_fast_assign(
 		__entry->drop = le32_to_cpu(ctrl_ctx->drop_flags);
 		__entry->add = le32_to_cpu(ctrl_ctx->add_flags);
 	),
-	TP_printk("%s", xhci_decode_ctrl_ctx(__entry->drop, __entry->add)
+	TP_printk("%s", xhci_decode_ctrl_ctx(__get_str(str), __entry->drop, __entry->add)
 	)
 );

@@ -555,13 +558,14 @@ DECLARE_EVENT_CLASS(xhci_log_doorbell,
 	TP_STRUCT__entry(
 		__field(u32, slot)
 		__field(u32, doorbell)
+		__dynamic_array(char, str, XHCI_MSG_MAX)
 	),
 	TP_fast_assign(
 		__entry->slot = slot;
 		__entry->doorbell = doorbell;
 	),
 	TP_printk("Ring doorbell for %s",
-		xhci_decode_doorbell(__entry->slot, __entry->doorbell)
+		  xhci_decode_doorbell(__get_str(str), __entry->slot, __entry->doorbell)
 	)
 );

drivers/usb/host/xhci.h +8 ~~-13~~

index 99ae9994f5eb..dca6181c33fd 100644
@@ -2460,10 +2460,9 @@ static inline const char *xhci_decode_trb(char *str, size_t size,
 	return str;
 }
 
-static inline const char *xhci_decode_ctrl_ctx(unsigned long drop,
-					       unsigned long add)
+static inline const char *xhci_decode_ctrl_ctx(char *str,
+		unsigned long drop, unsigned long add)
 {
-	static char	str[1024];
 	unsigned int	bit;
 	int		ret = 0;

@@ -2489,10 +2488,9 @@ static inline const char *xhci_decode_ctrl_ctx(unsigned long drop,
 	return str;
 }
 
-static inline const char *xhci_decode_slot_context(u32 info, u32 info2,
-		u32 tt_info, u32 state)
+static inline const char *xhci_decode_slot_context(char *str,
+		u32 info, u32 info2, u32 tt_info, u32 state)
 {
-	static char str[1024];
 	u32 speed;
 	u32 hub;
 	u32 mtt;

@@ -2621,9 +2619,8 @@ static inline const char *xhci_decode_portsc(char *str, u32 portsc)
 	return str;
 }
 
-static inline const char *xhci_decode_usbsts(u32 usbsts)
+static inline const char *xhci_decode_usbsts(char *str, u32 usbsts)
 {
-	static char str[256];
 	int ret = 0;
 
 	if (usbsts == ~(u32)0)

@@ -2650,9 +2647,8 @@ static inline const char *xhci_decode_usbsts(u32 usbsts)
 	return str;
 }
 
-static inline const char *xhci_decode_doorbell(u32 slot, u32 doorbell)
+static inline const char *xhci_decode_doorbell(char *str, u32 slot, u32 doorbell)
 {
-	static char str[256];
 	u8 ep;
 	u16 stream;
 	int ret;

@@ -2719,10 +2715,9 @@ static inline const char *xhci_ep_type_string(u8 type)
 	}
 }
 
-static inline const char *xhci_decode_ep_context(u32 info, u32 info2, u64 deq,
-		u32 tx_info)
+static inline const char *xhci_decode_ep_context(char *str, u32 info,
+		u32 info2, u64 deq, u32 tx_info)
 {
-	static char str[1024];
 	int ret;
 
 	u32 esit;