diff options
| author | Alexander Gordeev <agordeev@linux.ibm.com> | 2021-08-06 12:55:08 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-09-15 09:50:27 +0200 |
| commit | 8b471e72b51e4d2617f27215da3f7840090fb22b (patch) | |
| tree | 344fe1bc074538cec0f094d75308748e7ac4ac84 /arch/s390 | |
| parent | 9d999957cb39ab7f37235808e006cf5b5bef536b (diff) | |
s390/kasan: fix large PMD pages address alignment check
[ Upstream commit ddd63c85ef67ea9ea7282ad35eafb6568047126e ]
It is currently possible to initialize a large PMD page when
the address is not aligned on page boundary.
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/mm/kasan_init.c | 41 |
1 files changed, 20 insertions, 21 deletions
diff --git a/arch/s390/mm/kasan_init.c b/arch/s390/mm/kasan_init.c index 5646b39c728a..e9a9b7b616bc 100644 --- a/arch/s390/mm/kasan_init.c +++ b/arch/s390/mm/kasan_init.c @@ -108,6 +108,9 @@ static void __init kasan_early_vmemmap_populate(unsigned long address, sgt_prot &= ~_SEGMENT_ENTRY_NOEXEC; } + /* + * The first 1MB of 1:1 mapping is mapped with 4KB pages + */ while (address < end) { pg_dir = pgd_offset_k(address); if (pgd_none(*pg_dir)) { @@ -165,30 +168,26 @@ static void __init kasan_early_vmemmap_populate(unsigned long address, pm_dir = pmd_offset(pu_dir, address); if (pmd_none(*pm_dir)) { - if (mode == POPULATE_ZERO_SHADOW && - IS_ALIGNED(address, PMD_SIZE) && + if (IS_ALIGNED(address, PMD_SIZE) && end - address >= PMD_SIZE) { - pmd_populate(&init_mm, pm_dir, - kasan_early_shadow_pte); - address = (address + PMD_SIZE) & PMD_MASK; - continue; - } - /* the first megabyte of 1:1 is mapped with 4k pages */ - if (has_edat && address && end - address >= PMD_SIZE && - mode != POPULATE_ZERO_SHADOW) { - void *page; - - if (mode == POPULATE_ONE2ONE) { - page = (void *)address; - } else { - page = kasan_early_alloc_segment(); - memset(page, 0, _SEGMENT_SIZE); + if (mode == POPULATE_ZERO_SHADOW) { + pmd_populate(&init_mm, pm_dir, kasan_early_shadow_pte); + address = (address + PMD_SIZE) & PMD_MASK; + continue; + } else if (has_edat && address) { + void *page; + + if (mode == POPULATE_ONE2ONE) { + page = (void *)address; + } else { + page = kasan_early_alloc_segment(); + memset(page, 0, _SEGMENT_SIZE); + } + pmd_val(*pm_dir) = __pa(page) | sgt_prot; + address = (address + PMD_SIZE) & PMD_MASK; + continue; } - pmd_val(*pm_dir) = __pa(page) | sgt_prot; - address = (address + PMD_SIZE) & PMD_MASK; - continue; } - pt_dir = kasan_early_pte_alloc(); pmd_populate(&init_mm, pm_dir, pt_dir); } else if (pmd_large(*pm_dir)) { |