[ Upstream commit eae21beecb ]
There's a logic inside GHES/CPER to detect if the section_length
is too small, but it doesn't detect if it is too big.
Currently, if the firmware receives an ARM processor CPER record
stating that a section length is big, kernel will blindly trust
section_length, producing a very long dump. For instance, a 67
bytes record with ERR_INFO_NUM set 46198 and section length
set to 854918320 would dump a lot of data going a way past the
firmware memory-mapped area.
Fix it by adding a logic to prevent it to go past the buffer
if ERR_INFO_NUM is too big, making it report instead:
[Hardware Error]: Hardware error from APEI Generic Hardware Error Source: 1
[Hardware Error]: event severity: recoverable
[Hardware Error]: Error 0, type: recoverable
[Hardware Error]: section_type: ARM processor error
[Hardware Error]: MIDR: 0xff304b2f8476870a
[Hardware Error]: section length: 854918320, CPER size: 67
[Hardware Error]: section length is too big
[Hardware Error]: firmware-generated error record is incorrect
[Hardware Error]: ERR_INFO_NUM is 46198
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
[ rjw: Subject and changelog tweaks ]
Link: https://patch.msgid.link/41cd9f6b3ace3cdff7a5e864890849e4b1c58b63.1767871950.git.mchehab+huawei@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
be10c1bdf6