!116 Before adding to usablemem_rgns, check if the memory range is already included.

From: @chenhaixaing 
Reviewed-by: @wangbin224 
Signed-off-by: @wangbin224

Before-adding-to-usablemem_rgns-check-if-the-memory-.patch

@@ -0,0 +1,56 @@
+From 13e0a9327a42d78b0c0d0f672e02d8013187251a Mon Sep 17 00:00:00 2001
+From: Chen Haixiang <chenhaixiang3@huawei.com>
+Date: Mon, 21 Oct 2024 20:00:25 +0800
+Subject: [PATCH] Before adding to usablemem_rgns, check if the memory range is
+ already included.
+
+When kexec_iomem_for_each_line() reads from /proc/iomem,
+concurrent modifications to /proc/iomem may lead to
+usablemem_rgns recording duplicate Crash kernel segments.
+This can result in the number of retrieved Crash kernel
+segments exceeding CRASH_MAX_RESERVED_RANGES, triggering
+a realloc of the crash_reserved_mem in usablemem_rgns,
+which could crash the process. We should ensure that each
+range added to usablemem_rgns is unique to prevent these issues.
+
+Reviewed-by: Louhongxiang <louhongxiang@huawei.com>
+Reviewed-by: wangbin <wangbin224@huawei.com>
+Reviewed-by: yangyanchao <yangyanchao6@huawei.com>
+Signed-off-by: chenhaixiang <chenhaixiang3@huawei.com>
+Signed-off-by: Simon Horman <horms@kernel.org>
+---
+ kexec/arch/arm64/crashdump-arm64.c | 16 ++++++++++++++--
+ 1 file changed, 14 insertions(+), 2 deletions(-)
+
+diff --git a/kexec/arch/arm64/crashdump-arm64.c b/kexec/arch/arm64/crashdump-arm64.c
+index 3098315..f23b2bf 100644
+--- a/kexec/arch/arm64/crashdump-arm64.c
++++ b/kexec/arch/arm64/crashdump-arm64.c
+@@ -63,10 +63,22 @@ static int iomem_range_callback(void *UNUSED(data), int UNUSED(nr),
+ 				char *str, unsigned long long base,
+ 				unsigned long long length)
+ {
+-	if (strncmp(str, CRASH_KERNEL, strlen(CRASH_KERNEL)) == 0)
++	int i;
++
++	if (strncmp(str, CRASH_KERNEL, strlen(CRASH_KERNEL)) == 0) {
++		/*
++		 * Checks whether the area exists in crash_reserved_mem.
++		 */
++		for (i = 0; i < usablemem_rgns.max_size; i++) {
++			if (usablemem_rgns.ranges[i].start == base) {
++				fprintf(stderr, "Warning, the range already exists in usablemem_rgns, base=%lx, length=%lx\n",
++						base, length);
++				return 0;
++			}
++		}
+ 		return mem_regions_alloc_and_add(&usablemem_rgns,
+ 						base, length, RANGE_RAM);
+-	else if (strncmp(str, SYSTEM_RAM, strlen(SYSTEM_RAM)) == 0)
++	} else if (strncmp(str, SYSTEM_RAM, strlen(SYSTEM_RAM)) == 0)
+ 		return mem_regions_alloc_and_add(&system_memory_rgns,
+ 						base, length, RANGE_RAM);
+ 	else if (strncmp(str, KERNEL_CODE, strlen(KERNEL_CODE)) == 0) {
+-- 
+2.43.0
+

kexec-tools.spec

@@ -4,7 +4,7 @@
 
 Name: kexec-tools
 Version: 2.0.26
-Release: 10
+Release: 11
 License: GPLv2
 Summary: The kexec/kdump userspace component
 URL:     https://www.kernel.org/
@@ -89,6 +89,7 @@ Patch0008:	Add-loongarch-iomem.h.patch
 Patch0009:	Fix-incorrect-page-exclusion-in-exclude_nodata_pages.patch
 Patch0010:	loongarch64-fix-kernel-image-size-error.patch
 %endif
+Patch0011:	Before-adding-to-usablemem_rgns-check-if-the-memory-.patch
 
 %description
 kexec-tools provides /sbin/kexec binary that facilitates a new
@@ -297,6 +298,9 @@ done
 %endif
 
 %changelog
+* Mon Feb 10 2025 chenhaixiang <chenhaixiang3@live.com> - 2.0.26-11
+- Before adding to usablemem_rgns, check if the memory range is already included.
+
 * Mon Jan 6 2025 Ming Wang <wangming01@loongson.cn> - 2.0.26-10
 - Fix loongarch kdump image size overflow issue.