vulnerability

Amazon Linux 2023: CVE-2024-26983: Important priority package update for kernel

Severity
5
CVSS
(AV:L/AC:L/Au:S/C:N/I:N/A:C)
Published
May 1, 2024
Added
Feb 17, 2025
Modified
Jul 9, 2025

Description

In the Linux kernel, the following vulnerability has been resolved:
bootconfig: use memblock_free_late to free xbc memory to buddy
On the time to free xbc memory in xbc_exit(), memblock may has handed
over memory to buddy allocator. So it doesn't make sense to free memory
back to memblock. memblock_free() called by xbc_exit() even causes UAF bugs
on architectures with CONFIG_ARCH_KEEP_MEMBLOCK disabled like x86.
Following KASAN logs shows this case.
This patch fixes the xbc memory free problem by calling memblock_free()
in early xbc init error rewind path and calling memblock_free_late() in
xbc exit path to free memory to buddy allocator.
[ 9.410890] ==================================================================
[ 9.418962] BUG: KASAN: use-after-free in memblock_isolate_range+0x12d/0x260
[ 9.426850] Read of size 8 at addr ffff88845dd30000 by task swapper/0/1
[ 9.435901] CPU: 9 PID: 1 Comm: swapper/0 Tainted: G U 6.9.0-rc3-00208-g586b5dfb51b9 #5
[ 9.446403] Hardware name: Intel Corporation RPLP LP5 (CPU:RaptorLake)/RPLP LP5 (ID:13), BIOS IRPPN02.01.01.00.00.19.015.D-00000000 Dec 28 2023
[ 9.460789] Call Trace:
[ 9.463518] <TASK>
[ 9.465859] dump_stack_lvl+0x53/0x70
[ 9.469949] print_report+0xce/0x610
[ 9.473944] ? __virt_addr_valid+0xf5/0x1b0
[ 9.478619] ? memblock_isolate_range+0x12d/0x260
[ 9.483877] kasan_report+0xc6/0x100
[ 9.487870] ? memblock_isolate_range+0x12d/0x260
[ 9.493125] memblock_isolate_range+0x12d/0x260
[ 9.498187] memblock_phys_free+0xb4/0x160
[ 9.502762] ? __pfx_memblock_phys_free+0x10/0x10
[ 9.508021] ? mutex_unlock+0x7e/0xd0
[ 9.512111] ? __pfx_mutex_unlock+0x10/0x10
[ 9.516786] ? kernel_init_freeable+0x2d4/0x430
[ 9.521850] ? __pfx_kernel_init+0x10/0x10
[ 9.526426] xbc_exit+0x17/0x70
[ 9.529935] kernel_init+0x38/0x1e0
[ 9.533829] ? _raw_spin_unlock_irq+0xd/0x30
[ 9.538601] ret_from_fork+0x2c/0x50
[ 9.542596] ? __pfx_kernel_init+0x10/0x10
[ 9.547170] ret_from_fork_asm+0x1a/0x30
[ 9.551552] </TASK>
[ 9.555649] The buggy address belongs to the physical page:
[ 9.561875] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x45dd30
[ 9.570821] flags: 0x200000000000000(node=0|zone=2)
[ 9.576271] page_type: 0xffffffff()
[ 9.580167] raw: 0200000000000000 ffffea0011774c48 ffffea0012ba1848 0000000000000000
[ 9.588823] raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
[ 9.597476] page dumped because: kasan: bad access detected
[ 9.605362] Memory state around the buggy address:
[ 9.610714] ffff88845dd2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 9.618786] ffff88845dd2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 9.626857] >ffff88845dd30000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 9.634930] ^
[ 9.638534] ffff88845dd30080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 9.646605] ffff88845dd30100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 9.654675] ==================================================================

Solutions

amazon-linux-2023-upgrade-bpftoolamazon-linux-2023-upgrade-bpftool-debuginfoamazon-linux-2023-upgrade-kernelamazon-linux-2023-upgrade-kernel-debuginfoamazon-linux-2023-upgrade-kernel-debuginfo-common-aarch64amazon-linux-2023-upgrade-kernel-debuginfo-common-x86-64amazon-linux-2023-upgrade-kernel-develamazon-linux-2023-upgrade-kernel-headersamazon-linux-2023-upgrade-kernel-libbpfamazon-linux-2023-upgrade-kernel-libbpf-develamazon-linux-2023-upgrade-kernel-libbpf-staticamazon-linux-2023-upgrade-kernel-livepatch-6-1-90-99-173amazon-linux-2023-upgrade-kernel-modules-extraamazon-linux-2023-upgrade-kernel-modules-extra-commonamazon-linux-2023-upgrade-kernel-toolsamazon-linux-2023-upgrade-kernel-tools-debuginfoamazon-linux-2023-upgrade-kernel-tools-develamazon-linux-2023-upgrade-perfamazon-linux-2023-upgrade-perf-debuginfoamazon-linux-2023-upgrade-python3-perfamazon-linux-2023-upgrade-python3-perf-debuginfo
Title
NEW

Explore Exposure Command

Confidently identify and prioritize exposures from endpoint to cloud with full attack surface visibility and threat-aware risk context.