| commit | 7e24eddac7f102d1cee2bba0ca8c939afda7288d | [log] [tgz] |
|---|---|---|
| author | Dan Williams <[email protected]> | Thu May 30 18:04:35 2024 -0700 |
| committer | Arnav Kansal <[email protected]> | Thu Oct 03 00:17:09 2024 +0000 |
| tree | 2c25b2132325c3f6a90502602b7b248854e7422b | |
| parent | 23e832f04b41d047cd19f1397363e06f704f3635 [diff] |
PCI: Add missing bridge lock to pci_bus_lock()
[ Upstream commit a4e772898f8bf2e7e1cf661a12c60a5612c4afab ]
One of the true positives that the cfg_access_lock lockdep effort
identified is this sequence:
WARNING: CPU: 14 PID: 1 at drivers/pci/pci.c:4886 pci_bridge_secondary_bus_reset+0x5d/0x70
RIP: 0010:pci_bridge_secondary_bus_reset+0x5d/0x70
Call Trace:
<TASK>
? __warn+0x8c/0x190
? pci_bridge_secondary_bus_reset+0x5d/0x70
? report_bug+0x1f8/0x200
? handle_bug+0x3c/0x70
? exc_invalid_op+0x18/0x70
? asm_exc_invalid_op+0x1a/0x20
? pci_bridge_secondary_bus_reset+0x5d/0x70
pci_reset_bus+0x1d8/0x270
vmd_probe+0x778/0xa10
pci_device_probe+0x95/0x120
Where pci_reset_bus() users are triggering unlocked secondary bus resets.
Ironically pci_bus_reset(), several calls down from pci_reset_bus(), uses
pci_bus_lock() before issuing the reset which locks everything *but* the
bridge itself.
For the same motivation as adding:
bridge = pci_upstream_bridge(dev);
if (bridge)
pci_dev_lock(bridge);
to pci_reset_function() for the "bus" and "cxl_bus" reset cases, add
pci_dev_lock() for @bus->self to pci_bus_lock().
BUG=b/370702700
TEST=presubmit
RELEASE_NOTE=Fixed CVE-2024-46750 in the Linux kernel.
cos-patch: security-moderate
Link: https://lore.kernel.org/r/171711747501.1628941.15217746952476635316.stgit@dwillia2-xfh.jf.intel.com
Reported-by: Imre Deak <[email protected]>
Closes: http://lore.kernel.org/r/[email protected]
Change-Id: I03b30d0fd70f2b4f30e5eff12d4ae28b9fe26c0a
Signed-off-by: Dan Williams <[email protected]>
Signed-off-by: Keith Busch <[email protected]>
[bhelgaas: squash in recursive locking deadlock fix from Keith Busch:
https: //lore.kernel.org/r/[email protected]]
Signed-off-by: Bjorn Helgaas <[email protected]>
Tested-by: Hans de Goede <[email protected]>
Tested-by: Kalle Valo <[email protected]>
Reviewed-by: Dave Jiang <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Kernel CVE Triage Automation <[email protected]>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/82522
Reviewed-by: Oleksandr Tymoshenko <[email protected]>
Reviewed-by: Arnav Kansal <[email protected]>
Tested-by: Cusky Presubmit Bot <[email protected]>