Go to file
Breno Leitao 41683624cb PCI/AER: Avoid NULL pointer dereference in aer_ratelimit()
commit deb2f22838 upstream.

When platform firmware supplies error information to the OS, e.g., via the
ACPI APEI GHES mechanism, it may identify an error source device that
doesn't advertise an AER Capability and therefore dev->aer_info, which
contains AER stats and ratelimiting data, is NULL.

pci_dev_aer_stats_incr() already checks dev->aer_info for NULL, but
aer_ratelimit() did not, leading to NULL pointer dereferences like this one
from the URL below:

  {1}[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 0
  {1}[Hardware Error]: event severity: corrected
  {1}[Hardware Error]:   device_id: 0000:00:00.0
  {1}[Hardware Error]:   vendor_id: 0x8086, device_id: 0x2020
  {1}[Hardware Error]:   aer_cor_status: 0x00001000, aer_cor_mask: 0x00002000
  BUG: kernel NULL pointer dereference, address: 0000000000000264
  RIP: 0010:___ratelimit+0xc/0x1b0
  pci_print_aer+0x141/0x360
  aer_recover_work_func+0xb5/0x130

[8086:2020] is an Intel "Sky Lake-E DMI3 Registers" device that claims to
be a Root Port but does not advertise an AER Capability.

Add a NULL check in aer_ratelimit() to avoid the NULL pointer dereference.
Note that this also prevents ratelimiting these events from GHES.

Fixes: a57f2bfb4a ("PCI/AER: Ratelimit correctable and non-fatal error logging")
Link: https://lore.kernel.org/r/buduna6darbvwfg3aogl5kimyxkggu3n4romnmq6sozut6axeu@clnx7sfsy457/
Signed-off-by: Breno Leitao <leitao@debian.org>
[bhelgaas: add crash details to commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20250929-aer_crash_2-v1-1-68ec4f81c356@debian.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-15 12:04:22 +02:00
2025-10-15 12:04:20 +02:00
2022-09-28 09:02:20 +02:00
2025-02-19 14:53:27 -07:00
2025-10-12 13:01:58 +02:00
2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 4.7 GiB
Languages
C 97.7%
Assembly 1.3%
Shell 0.3%
Makefile 0.3%
Python 0.2%
Other 0.1%