In the Linux kernel, the following vulnerability has been resolved:
powerpc/fadump: Move fadump_cma_init to setup_arch() after initmem_init()
During early init CMA_MIN_ALIGNMENT_BYTES can be PAGE_SIZE,
since pageblock_order is still zero and it gets initialized
later during initmem_init() e.g.
setup_arch() -> initmem_init() -> sparse_init() -> set_pageblock_order()
One such use case where this causes issue is -
early_setup() -> early_init_devtree() -> fadump_reserve_mem() -> fadump_cma_init()
This causes CMA memory alignment check to be bypassed in
cma_init_reserved_mem(). Then later cma_activate_area() can hit
a VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) if the reserved memory
area was not pageblock_order aligned.
Fix it by moving the fadump_cma_init() after initmem_init(),
where other such cma reservations also gets called.
<stack trace>
==============
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10010
flags: 0x13ffff800000000(node=1|zone=0|lastcpupid=0x7ffff) CMA
raw: 013ffff800000000 5deadbeef0000100 5deadbeef0000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: VM_BUG_ON_PAGE(pfn & ((1 << order) - 1))
------------[ cut here ]------------
kernel BUG at mm/page_alloc.c:778!
Call Trace:
__free_one_page+0x57c/0x7b0 (unreliable)
free_pcppages_bulk+0x1a8/0x2c8
free_unref_page_commit+0x3d4/0x4e4
free_unref_page+0x458/0x6d0
init_cma_reserved_pageblock+0x114/0x198
cma_init_reserved_areas+0x270/0x3e0
do_one_initcall+0x80/0x2f8
kernel_init_freeable+0x33c/0x530
kernel_init+0x34/0x26c
ret_from_kernel_user_thread+0x14/0x1c
Metrics
Affected Vendors & Products
References
History
Wed, 01 Jan 2025 14:30:00 +0000
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cvssV3_1
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cvssV3_1
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Mon, 30 Dec 2024 01:30:00 +0000
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threat_severity
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cvssV3_1
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Sat, 28 Dec 2024 10:00:00 +0000
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Description | In the Linux kernel, the following vulnerability has been resolved: powerpc/fadump: Move fadump_cma_init to setup_arch() after initmem_init() During early init CMA_MIN_ALIGNMENT_BYTES can be PAGE_SIZE, since pageblock_order is still zero and it gets initialized later during initmem_init() e.g. setup_arch() -> initmem_init() -> sparse_init() -> set_pageblock_order() One such use case where this causes issue is - early_setup() -> early_init_devtree() -> fadump_reserve_mem() -> fadump_cma_init() This causes CMA memory alignment check to be bypassed in cma_init_reserved_mem(). Then later cma_activate_area() can hit a VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) if the reserved memory area was not pageblock_order aligned. Fix it by moving the fadump_cma_init() after initmem_init(), where other such cma reservations also gets called. <stack trace> ============== page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10010 flags: 0x13ffff800000000(node=1|zone=0|lastcpupid=0x7ffff) CMA raw: 013ffff800000000 5deadbeef0000100 5deadbeef0000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: VM_BUG_ON_PAGE(pfn & ((1 << order) - 1)) ------------[ cut here ]------------ kernel BUG at mm/page_alloc.c:778! Call Trace: __free_one_page+0x57c/0x7b0 (unreliable) free_pcppages_bulk+0x1a8/0x2c8 free_unref_page_commit+0x3d4/0x4e4 free_unref_page+0x458/0x6d0 init_cma_reserved_pageblock+0x114/0x198 cma_init_reserved_areas+0x270/0x3e0 do_one_initcall+0x80/0x2f8 kernel_init_freeable+0x33c/0x530 kernel_init+0x34/0x26c ret_from_kernel_user_thread+0x14/0x1c | |
Title | powerpc/fadump: Move fadump_cma_init to setup_arch() after initmem_init() | |
References |
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Status: PUBLISHED
Assigner: Linux
Published: 2024-12-28T09:46:06.497Z
Updated: 2025-05-04T10:02:02.434Z
Reserved: 2024-12-27T15:00:39.845Z
Link: CVE-2024-56677

No data.

Status : Received
Published: 2024-12-28T10:15:08.277
Modified: 2024-12-28T10:15:08.277
Link: CVE-2024-56677
