Messages in this thread | | | Date | Thu, 27 Jul 2023 07:58:31 +0300 | From | Mike Rapoport <> | Subject | [GIT PULL] memblock fixes for v6.5-rc4 |
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Hi Linus,
The following changes since commit 6eaae198076080886b9e7d57f4ae06fa782f90ef:
Linux 6.5-rc3 (2023-07-23 15:24:10 -0700)
are available in the Git repository at:
https://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock.git tags/fixes-2023-07-27
for you to fetch changes up to 9e46e4dcd9d6cd88342b028dbfa5f4fb7483d39c:
mm,memblock: reset memblock.reserved to system init state to prevent UAF (2023-07-24 08:52:56 +0300)
---------------------------------------------------------------- memblock: reset memblock.reserved to system init state to prevent UAF
A call to memblock_free() or memblock_phys_free() issued after memblock data is discarded will result in use after free in memblock_isolate_range().
When CONFIG_KASAN is enabled, this will cause a panic early in boot. Without CONFIG_KASAN, there is a chance that memblock_isolate_range() might scribble on memory that is now in use by somebody else.
Avoid those issues by making sure that memblock_discard points memblock.reserved.regions back at the static buffer.
If memblock_free() or memblock_phys_free() is called after memblock memory is discarded, that will print a warning in memblock_remove_region().
---------------------------------------------------------------- Rik van Riel (1): mm,memblock: reset memblock.reserved to system init state to prevent UAF
mm/memblock.c | 4 ++++ 1 file changed, 4 insertions(+)
-- Sincerely yours, Mike.
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