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FAILED: patch "[PATCH] usb: free iso schedules on failed submit" failed to apply to 6.1-stable tree

PATCH New [email protected] 2 participants 2 messages Jul 14 – Jul 19

Subsystems (4)
Stable branch USB USB ehci driver Faraday FOTG210 USB2 dual-role controller
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#0 lore raw

The patch below does not apply to the 6.1-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]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x b9399d25fbb34a05bbe76eeedd730f62ff2670e9
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026071433-debating-yonder-99d6@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

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

From b9399d25fbb34a05bbe76eeedd730f62ff2670e9 Mon Sep 17 00:00:00 2001
From: Dawei Feng <[email protected]>
Date: Tue, 30 Jun 2026 15:14:19 +0800
Subject: [PATCH] usb: free iso schedules on failed submit

EHCI and FOTG210 isochronous submits build an ehci_iso_sched before linking the URB to the endpoint queue, and keep the staged schedule in urb->hcpriv until iso_stream_schedule() and the link helpers consume it. If the controller is no longer accessible, or usb_hcd_link_urb_to_ep() fails, submit jumps to done_not_linked before that handoff happens and leaks the staged schedule still attached to urb->hcpriv.

Free the staged schedule from done_not_linked when submit fails before the URB is linked and clear urb->hcpriv after the free.

The bug was first flagged by an experimental analysis tool we are developing for kernel memory-management bugs while analyzing v6.13-rc1. The tool is still under development and is not yet publicly available. Manual inspection confirms that the bug is still present in v7.1.1.

An x86_64 allyesconfig build showed no new warnings. As we do not have an EHCI host controller with a USB isochronous device to test with, no runtime testing was able to be performed.

Fixes 8de98402652c ("[PATCH] USB: Fix USB suspend/resume crasher (#2)")
Fixes e9df41c5c589 ("USB: make HCDs responsible for managing endpoint queues")
Fixes 7d50195f6c50 ("usb: host: Faraday fotg210-hcd driver")
Cc stable <[email protected]>
Signed-off-by Dawei Feng <[email protected]>
Reviewed-by Alan Stern <[email protected]>
Link https://patch.msgid.link/[email protected] open here
Signed-off-by Greg Kroah-Hartman <[email protected]>
drivers/usb/fotg210/fotg210-hcd.c +4 -2
index 1a48329a4e08..956be5b56510 100644
@@ -4267,8 +4267,6 @@ static int iso_stream_schedule(struct fotg210_hcd *fotg210, struct urb *urb,
 	return 0;
 
 fail:
-	iso_sched_free(stream, sched);
-	urb->hcpriv = NULL;
 	return status;
 }
 

@@ -4562,6 +4560,10 @@ static int itd_submit(struct fotg210_hcd *fotg210, struct urb *urb,
 	else
 		usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
 done_not_linked:
+	if (status < 0) {
+		iso_sched_free(stream, urb->hcpriv);
+		urb->hcpriv = NULL;
+	}
 	spin_unlock_irqrestore(&fotg210->lock, flags);
 done:
 	return status;
drivers/usb/host/ehci-sched.c +9 -2
index a241337c9af8..57d07d1c2dfa 100644
@@ -1623,6 +1623,7 @@ iso_stream_schedule(
 			status = 1;	/* and give it back immediately */
 			iso_sched_free(stream, sched);
 			sched = NULL;
+			urb->hcpriv = NULL;
 		}
 	}
 	urb->error_count = skip / period;

@@ -1653,8 +1654,6 @@ iso_stream_schedule(
 	return status;
 
  fail:
-	iso_sched_free(stream, sched);
-	urb->hcpriv = NULL;
 	return status;
 }
 

@@ -1966,6 +1965,10 @@ static int itd_submit(struct ehci_hcd *ehci, struct urb *urb,
 		usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
 	}
  done_not_linked:
+	if (status < 0) {
+		iso_sched_free(stream, urb->hcpriv);
+		urb->hcpriv = NULL;
+	}
 	spin_unlock_irqrestore(&ehci->lock, flags);
  done:
 	return status;

@@ -2343,6 +2346,10 @@ static int sitd_submit(struct ehci_hcd *ehci, struct urb *urb,
 		usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
 	}
  done_not_linked:
+	if (status < 0) {
+		iso_sched_free(stream, urb->hcpriv);
+		urb->hcpriv = NULL;
+	}
 	spin_unlock_irqrestore(&ehci->lock, flags);
  done:
 	return status;
maintainer
#1 lore raw

PATCH 1/1 usb: free iso schedules on failed submit

From: Dawei Feng <[email protected]>

[ Upstream commit b9399d25fbb34a05bbe76eeedd730f62ff2670e9 ]

EHCI and FOTG210 isochronous submits build an ehci_iso_sched before linking the URB to the endpoint queue, and keep the staged schedule in urb->hcpriv until iso_stream_schedule() and the link helpers consume it. If the controller is no longer accessible, or usb_hcd_link_urb_to_ep() fails, submit jumps to done_not_linked before that handoff happens and leaks the staged schedule still attached to urb->hcpriv.

Free the staged schedule from done_not_linked when submit fails before the URB is linked and clear urb->hcpriv after the free.

The bug was first flagged by an experimental analysis tool we are developing for kernel memory-management bugs while analyzing v6.13-rc1. The tool is still under development and is not yet publicly available. Manual inspection confirms that the bug is still present in v7.1.1.

An x86_64 allyesconfig build showed no new warnings. As we do not have an EHCI host controller with a USB isochronous device to test with, no runtime testing was able to be performed.

Fixes 8de98402652c ("[PATCH] USB: Fix USB suspend/resume crasher (#2)")
Fixes e9df41c5c589 ("USB: make HCDs responsible for managing endpoint queues")
Fixes 7d50195f6c50 ("usb: host: Faraday fotg210-hcd driver")
Cc stable <[email protected]>
Signed-off-by Dawei Feng <[email protected]>
Reviewed-by Alan Stern <[email protected]>
Link https://patch.msgid.link/[email protected] open here
Signed-off-by Greg Kroah-Hartman <[email protected]>
Signed-off-by Sasha Levin <[email protected]>
---
 drivers/usb/host/ehci-sched.c  | 11 +++++++++--
 drivers/usb/host/fotg210-hcd.c |  6 ++++--
 2 files changed, 13 insertions(+), 4 deletions(-)
drivers/usb/host/ehci-sched.c +9 -2
index bd542b6fc46bda..d002e70171f6c4 100644
@@ -1623,6 +1623,7 @@ iso_stream_schedule(
 			status = 1;	/* and give it back immediately */
 			iso_sched_free(stream, sched);
 			sched = NULL;
+			urb->hcpriv = NULL;
 		}
 	}
 	urb->error_count = skip / period;

@@ -1653,8 +1654,6 @@ iso_stream_schedule(
 	return status;
 
  fail:
-	iso_sched_free(stream, sched);
-	urb->hcpriv = NULL;
 	return status;
 }
 

@@ -1966,6 +1965,10 @@ static int itd_submit(struct ehci_hcd *ehci, struct urb *urb,
 		usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
 	}
  done_not_linked:
+	if (status < 0) {
+		iso_sched_free(stream, urb->hcpriv);
+		urb->hcpriv = NULL;
+	}
 	spin_unlock_irqrestore(&ehci->lock, flags);
  done:
 	return status;

@@ -2343,6 +2346,10 @@ static int sitd_submit(struct ehci_hcd *ehci, struct urb *urb,
 		usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
 	}
  done_not_linked:
+	if (status < 0) {
+		iso_sched_free(stream, urb->hcpriv);
+		urb->hcpriv = NULL;
+	}
 	spin_unlock_irqrestore(&ehci->lock, flags);
  done:
 	return status;
drivers/usb/host/fotg210-hcd.c +4 -2
index dc968960769e1b..5cdae91211ece0 100644
@@ -4272,8 +4272,6 @@ static int iso_stream_schedule(struct fotg210_hcd *fotg210, struct urb *urb,
 	return 0;
 
 fail:
-	iso_sched_free(stream, sched);
-	urb->hcpriv = NULL;
 	return status;
 }
 

@@ -4567,6 +4565,10 @@ static int itd_submit(struct fotg210_hcd *fotg210, struct urb *urb,
 	else
 		usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
 done_not_linked:
+	if (status < 0) {
+		iso_sched_free(stream, urb->hcpriv);
+		urb->hcpriv = NULL;
+	}
 	spin_unlock_irqrestore(&fotg210->lock, flags);
 done:
 	return status;
Signature · 1 line
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