linux_dsm_epyc7002/arch/ia64
Sergei Trofimovich 1dc55c3a48 ia64: module: fix symbolizer crash on fdescr
[ Upstream commit 99e729bd40fb3272fa4b0140839d5e957b58588a ]

Noticed failure as a crash on ia64 when tried to symbolize all backtraces
collected by page_owner=on:

    $ cat /sys/kernel/debug/page_owner
    <oops>

    CPU: 1 PID: 2074 Comm: cat Not tainted 5.12.0-rc4 #226
    Hardware name: hp server rx3600, BIOS 04.03 04/08/2008
    ip is at dereference_module_function_descriptor+0x41/0x100

Crash happens at dereference_module_function_descriptor() due to
use-after-free when dereferencing ".opd" section header.

All section headers are already freed after module is laoded successfully.

To keep symbolizer working the change stores ".opd" address and size after
module is relocated to a new place and before section headers are
discarded.

To make similar errors less obscure module_finalize() now zeroes out all
variables relevant to module loading only.

Link: https://lkml.kernel.org/r/20210403074803.3309096-1-slyfox@gentoo.org
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-19 10:12:59 +02:00
..
configs ia64: remove duplicate entries in generic_defconfig 2021-04-21 13:00:57 +02:00
hp/common dma-mapping: split <linux/dma-mapping.h> 2020-10-06 07:07:03 +02:00
include ia64: module: fix symbolizer crash on fdescr 2021-05-19 10:12:59 +02:00
kernel ia64: module: fix symbolizer crash on fdescr 2021-05-19 10:12:59 +02:00
lib Merge branch 'work.csum_and_copy' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-12 16:24:13 -07:00
mm ia64: fix discontig.c section mismatches 2021-04-28 13:40:02 +02:00
oprofile ia64: Remove perfmon 2020-09-11 09:34:32 -07:00
pci ia64: remove support for machvecs 2019-08-16 14:32:26 -07:00
scripts ia64: convert unwcheck.py to python3 2018-03-05 14:35:01 -08:00
uv ia64: remove support for machvecs 2019-08-16 14:32:26 -07:00
install.sh kbuild: use INSTALLKERNEL to select customized installkernel script 2009-09-20 12:18:14 +02:00
Kconfig Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-10-22 09:59:21 -07:00
Kconfig.debug ia64: remove support for machvecs 2019-08-16 14:32:26 -07:00
Makefile kbuild: preprocess module linker script 2020-09-25 00:36:41 +09:00