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| author | Alexander Gordeev <agordeev@linux.ibm.com> | 2021-08-06 12:55:08 +0200 |
|---|---|---|
| committer | Heiko Carstens <hca@linux.ibm.com> | 2021-08-25 11:03:33 +0200 |
| commit | ddd63c85ef67ea9ea7282ad35eafb6568047126e (patch) | |
| tree | d8f478d2d1d902166bc26850ee2b3b88cbe6cd95 /arch/s390/mm | |
| parent | c42257d64079f41af5debcba9dcd15dad3b2969e (diff) | |
| download | linux-ddd63c85ef67ea9ea7282ad35eafb6568047126e.tar.bz2 | |
s390/kasan: fix large PMD pages address alignment check
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>
Diffstat (limited to 'arch/s390/mm')
| -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 facbf64d98ad..3e4735168019 100644 --- a/arch/s390/mm/kasan_init.c +++ b/arch/s390/mm/kasan_init.c @@ -107,6 +107,9 @@ static void __init kasan_early_pgtable_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)) { @@ -157,30 +160,26 @@ static void __init kasan_early_pgtable_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)) { |