Fix for "kmem -s|-S" option on Linux 5.7 and later kernels

Release crash-7.3.0-2

Resolves: rhbz#1954913

Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
This commit is contained in:
Lianbo Jiang 2021-06-11 18:51:47 +08:00
parent a3933d5c86
commit a3ae8fcfd1
2 changed files with 64 additions and 1 deletions

View File

@ -0,0 +1,58 @@
From 647a5c33e1c94054d7b63168cd6c12901591cb77 Mon Sep 17 00:00:00 2001
From: Lianbo Jiang <lijiang@redhat.com>
Date: Thu, 27 May 2021 18:02:11 +0800
Subject: [PATCH] Fix for "kmem -s|-S" option on Linux 5.7 and later kernels
Linux 5.7 and later kernels that contain kernel commit 1ad53d9fa3f6
("slub: improve bit diffusion for freelist ptr obfuscation") changed
the calculation formula in the freelist_ptr(), which added a swab()
call to mix bits a little more. When kernel is configured with the
"CONFIG_SLAB_FREELIST_HARDENED=y", without the patch, the "kmem -s|-S"
options display wrong statistics and state whether slab objects are
in use or free and can print the following errors:
crash> kmem -s
CACHE OBJSIZE ALLOCATED TOTAL SLABS SSIZE NAME
87201e00 528 0 0 0 8k xfs_dqtrx
87201f00 496 0 0 0 8k xfs_dquot
kmem: xfs_buf: slab: 37202e6e900 invalid freepointer: b844bab900001d70
kmem: xfs_buf: slab: 3720250fd80 invalid freepointer: b8603f9400001370
...
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
---
memory.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/memory.c b/memory.c
index 8c6bbe409922..a3cf8a86728d 100644
--- a/memory.c
+++ b/memory.c
@@ -20,6 +20,7 @@
#include <sys/mman.h>
#include <ctype.h>
#include <netinet/in.h>
+#include <byteswap.h>
struct meminfo { /* general purpose memory information structure */
ulong cache; /* used by the various memory searching/dumping */
@@ -19336,10 +19337,14 @@ count_free_objects(struct meminfo *si, ulong freelist)
static ulong
freelist_ptr(struct meminfo *si, ulong ptr, ulong ptr_addr)
{
- if (VALID_MEMBER(kmem_cache_random))
+ if (VALID_MEMBER(kmem_cache_random)) {
/* CONFIG_SLAB_FREELIST_HARDENED */
+
+ if (THIS_KERNEL_VERSION >= LINUX(5,7,0))
+ ptr_addr = (sizeof(long) == 8) ? bswap_64(ptr_addr)
+ : bswap_32(ptr_addr);
return (ptr ^ si->random ^ ptr_addr);
- else
+ } else
return ptr;
}
--
2.30.2

View File

@ -4,7 +4,7 @@
Summary: Kernel analysis utility for live systems, netdump, diskdump, kdump, LKCD or mcore dumpfiles
Name: crash
Version: 7.3.0
Release: 1%{?dist}
Release: 2%{?dist}
License: GPLv3
Source0: https://github.com/crash-utility/crash/archive/crash-%{version}.tar.gz
Source1: http://ftp.gnu.org/gnu/gdb/gdb-7.6.tar.gz
@ -18,6 +18,7 @@ Requires: binutils
Provides: bundled(libiberty)
Provides: bundled(gdb) = 7.6
Patch0: lzo_snappy.patch
Patch1: 0001-Fix-for-kmem-s-S-option-on-Linux-5.7-and-later-kerne.patch
%description
The core analysis suite is a self-contained tool that can be used to
@ -38,6 +39,7 @@ offered by Mission Critical Linux, or the LKCD kernel patch.
%prep
%setup -n %{name}-%{version} -q
%patch0 -p1 -b lzo_snappy.patch
%patch1 -p1
%build
# This package has an internal copy of GDB which has broken configure code for
@ -69,6 +71,9 @@ cp -p defs.h %{buildroot}%{_includedir}/crash
%{_includedir}/*
%changelog
* Fri Jun 11 2021 Lianbo Jiang <lijiang@redhat.com> - 7.3.0-2
- Fix for "kmem -s|-S" option on Linux 5.7 and later kernels
* Mon May 10 2021 Lianbo Jiang <lijiang@redhat.com> - 7.3.0-1
- Rebase to upstream 7.3.0