Messages in this thread Patch in this message | | | From | Alexandre Ghiti <> | Subject | [PATCH] riscv: Add KASAN_VMALLOC support | Date | Thu, 25 Feb 2021 02:42:27 -0500 |
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Populate the top-level of the kernel page table to implement KASAN_VMALLOC, lower levels are filled dynamically upon memory allocation at runtime.
Co-developed-by: Nylon Chen <nylon7@andestech.com> Signed-off-by: Nylon Chen <nylon7@andestech.com> Co-developed-by: Nick Hu <nickhu@andestech.com> Signed-off-by: Nick Hu <nickhu@andestech.com> Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> --- arch/riscv/Kconfig | 1 + arch/riscv/mm/kasan_init.c | 35 ++++++++++++++++++++++++++++++++++- 2 files changed, 35 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 8eadd1cbd524..3832a537c5d6 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -57,6 +57,7 @@ config RISCV select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_JUMP_LABEL_RELATIVE select HAVE_ARCH_KASAN if MMU && 64BIT + select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT select HAVE_ARCH_KGDB select HAVE_ARCH_KGDB_QXFER_PKT select HAVE_ARCH_MMAP_RND_BITS if MMU diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c index 719b6e4d6075..171569df4334 100644 --- a/arch/riscv/mm/kasan_init.c +++ b/arch/riscv/mm/kasan_init.c @@ -142,6 +142,31 @@ static void __init kasan_populate(void *start, void *end) memset(start, KASAN_SHADOW_INIT, end - start); } +void __init kasan_shallow_populate_pgd(unsigned long vaddr, unsigned long end) +{ + unsigned long next; + void *p; + pgd_t *pgd_k = pgd_offset_k(vaddr); + + do { + next = pgd_addr_end(vaddr, end); + if (pgd_page_vaddr(*pgd_k) == (unsigned long)lm_alias(kasan_early_shadow_pmd)) { + p = memblock_alloc(PAGE_SIZE, PAGE_SIZE); + set_pgd(pgd_k, pfn_pgd(PFN_DOWN(__pa(p)), PAGE_TABLE)); + } + } while (pgd_k++, vaddr = next, vaddr != end); +} + +void __init kasan_shallow_populate(void *start, void *end) +{ + unsigned long vaddr = (unsigned long)start & PAGE_MASK; + unsigned long vend = PAGE_ALIGN((unsigned long)end); + + kasan_shallow_populate_pgd(vaddr, vend); + + local_flush_tlb_all(); +} + void __init kasan_init(void) { phys_addr_t _start, _end; @@ -149,7 +174,15 @@ void __init kasan_init(void) kasan_populate_early_shadow((void *)KASAN_SHADOW_START, (void *)kasan_mem_to_shadow((void *) - VMALLOC_END)); + VMEMMAP_END)); + if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) + kasan_shallow_populate( + (void *)kasan_mem_to_shadow((void *)VMALLOC_START), + (void *)kasan_mem_to_shadow((void *)VMALLOC_END)); + else + kasan_populate_early_shadow( + (void *)kasan_mem_to_shadow((void *)VMALLOC_START), + (void *)kasan_mem_to_shadow((void *)VMALLOC_END)); for_each_mem_range(i, &_start, &_end) { void *start = (void *)_start; -- 2.20.1
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