linux/drivers/pci/msi
Vidya Sagar db744ddd59 PCI/MSI: Prevent MSI hardware interrupt number truncation
While calculating the hardware interrupt number for a MSI interrupt, the
higher bits (i.e. from bit-5 onwards a.k.a domain_nr >= 32) of the PCI
domain number gets truncated because of the shifted value casting to return
type of pci_domain_nr() which is 'int'. This for example is resulting in
same hardware interrupt number for devices 0019:00:00.0 and 0039:00:00.0.

To address this cast the PCI domain number to 'irq_hw_number_t' before left
shifting it to calculate the hardware interrupt number.

Please note that this fixes the issue only on 64-bit systems and doesn't
change the behavior for 32-bit systems i.e. the 32-bit systems continue to
have the issue. Since the issue surfaces only if there are too many PCIe
controllers in the system which usually is the case in modern server
systems and they don't tend to run 32-bit kernels.

Fixes: 3878eaefb8 ("PCI/MSI: Enhance core to support hierarchy irqdomain")
Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240115135649.708536-1-vidyas@nvidia.com
2024-02-19 16:11:01 +01:00
..
api.c PCI/MSI: Clarify usage of pci_msix_free_irq() 2023-02-21 08:25:14 +01:00
irqdomain.c PCI/MSI: Prevent MSI hardware interrupt number truncation 2024-02-19 16:11:01 +01:00
legacy.c PCI/MSI: Prevent UAF in error path 2022-01-21 02:14:46 +01:00
Makefile PCI/MSI: Move pci_disable_msi() to api.c 2022-11-17 15:15:20 +01:00
msi.c PCI/MSI: Use FIELD_GET/PREP() 2023-10-24 10:54:04 -05:00
msi.h PCI/MSI: Split MSI-X descriptor setup 2022-12-05 22:22:34 +01:00
pcidev_msi.c