cbcvebase.
CVE-2024-26983
published 2024-05-01

CVE-2024-26983: 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…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.23%
14.0th percentile
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] [ 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] [ 9.555649] The buggy address belongs to the physical

Affected

24 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.90-1 (bookworm)linux 6.1.90-1 (bookworm)
linuxlinux
linuxlinux>= 40caa127f3c7279c75cb0c9684559fa314ee3a66 < 1e7feb31a18c197d63a5e606025ed63c762f89181e7feb31a18c197d63a5e606025ed63c762f8918
linuxlinux>= 40caa127f3c7279c75cb0c9684559fa314ee3a66 < e46d3be714ad9652480c6db129ab8125e2d20ab7e46d3be714ad9652480c6db129ab8125e2d20ab7
linuxlinux>= 40caa127f3c7279c75cb0c9684559fa314ee3a66 < 5a7dfb8fcd3f29fc93161100179b27f24f3d5f355a7dfb8fcd3f29fc93161100179b27f24f3d5f35
linuxlinux>= 40caa127f3c7279c75cb0c9684559fa314ee3a66 < 89f9a1e876b5a7ad884918c03a46831af202c8a089f9a1e876b5a7ad884918c03a46831af202c8a0
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.1.90-16.1.90-1
linuxlinux_kernel>= 0 < 6.8.9-16.8.9-1
linuxlinux_kernel>= 0 < 6.8.9-16.8.9-1
linuxlinux_kernel>= 0 < 6.8.0-38.386.8.0-38.38
linuxlinux_kernel>= 5.15 < 6.1.886.1.88
linuxlinux_kernel>= 6.2 < 6.6.296.6.29
linuxlinux_kernel>= 6.7 < 6.8.86.8.8
msrcazl3_hyperv-daemons_6.6.22.1-2_on_azure_linux_3.0
msrcazl3_hyperv-daemons_6.6.35.1-1_on_azure_linux_3.0
msrcazure_linux_3.0_arm
msrcazure_linux_3.0_x64
msrccbl2_hyperv-daemons_5.15.180.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.200.1-1_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.202.1-1_on_cbl_mariner_2.0
msrccbl_mariner_2.0_arm
msrccbl_mariner_2.0_x64

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu4.6MEDIUM
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