In the Linux kernel, the following vulnerability has been resolved:
mm/vmalloc: fix page mapping if vm_area_alloc_pages() with high order fallback to order 0
The __vmap_pages_range_noflush() assumes its argument pages** contains
pages with the same page shift. However, since commit e9c3cda4d86e (“mm,
vmalloc: fix high order __GFP_NOFAIL allocations”), if gfp_flags includes
__GFP_NOFAIL with high order in vm_area_alloc_pages() and page allocation
failed for high order, the pages** may contain two different page shifts
(high order and order-0). This could lead __vmap_pages_range_noflush() to
perform incorrect mappings, potentially resulting in memory corruption.
Users might encounter this as follows (vmap_allow_huge = true, 2M is for
PMD_SIZE):
kvmalloc(2M, __GFP_NOFAIL|GFP_X)
__vmalloc_node_range_noprof(vm_flags=VM_ALLOW_HUGE_VMAP)
vm_area_alloc_pages(order=9) —> order-9 allocation failed and fallback to order-0
vmap_pages_range()
vmap_pages_range_noflush()
__vmap_pages_range_noflush(page_shift = 21) ----> wrong mapping happens
We can remove the fallback code because if a high-order allocation fails,
__vmalloc_node_range_noprof() will retry with order-0. Therefore, it is
unnecessary to fallback to order-0 here. Therefore, fix this by removing
the fallback code.
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"mm/vmalloc.c"
],
"versions": [
{
"version": "fe5c2bdcb14c",
"lessThan": "fd1ffbb50ef4",
"status": "affected",
"versionType": "git"
},
{
"version": "e9c3cda4d86e",
"lessThan": "de7bad86345c",
"status": "affected",
"versionType": "git"
},
{
"version": "e9c3cda4d86e",
"lessThan": "c91618816f4d",
"status": "affected",
"versionType": "git"
},
{
"version": "e9c3cda4d86e",
"lessThan": "61ebe5a747da",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"mm/vmalloc.c"
],
"versions": [
{
"version": "6.3",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.3",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.1.107",
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.6.48",
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.10.7",
"lessThanOrEqual": "6.10.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "6.11",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]