For instrumenting global variables KASan will shadow memory backing memory for modules. So on module loading we will need to allocate shadow memory and map it at exact virtual address. __vmalloc_node_range() seems like the best fit for that purpose, except it puts a guard hole after allocated area. Now we have VM_NO_GUARD flag disabling guard page, so we need to pass into __vmalloc_node_range(). Add new parameter 'vm_flags' to __vmalloc_node_range() function. Signed-off-by: Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx> --- arch/arm/kernel/module.c | 2 +- arch/arm64/kernel/module.c | 4 ++-- arch/mips/kernel/module.c | 2 +- arch/parisc/kernel/module.c | 2 +- arch/s390/kernel/module.c | 2 +- arch/sparc/kernel/module.c | 2 +- arch/unicore32/kernel/module.c | 2 +- arch/x86/kernel/module.c | 2 +- include/linux/vmalloc.h | 4 +++- mm/vmalloc.c | 10 ++++++---- 10 files changed, 18 insertions(+), 14 deletions(-) diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c index bea7db9..2e11961 100644 --- a/arch/arm/kernel/module.c +++ b/arch/arm/kernel/module.c @@ -41,7 +41,7 @@ void *module_alloc(unsigned long size) { return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, - GFP_KERNEL, PAGE_KERNEL_EXEC, NUMA_NO_NODE, + GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE, __builtin_return_address(0)); } #endif diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c index 9b6f71d..67bf410 100644 --- a/arch/arm64/kernel/module.c +++ b/arch/arm64/kernel/module.c @@ -35,8 +35,8 @@ void *module_alloc(unsigned long size) { return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, - GFP_KERNEL, PAGE_KERNEL_EXEC, NUMA_NO_NODE, - __builtin_return_address(0)); + GFP_KERNEL, PAGE_KERNEL_EXEC, 0, + NUMA_NO_NODE, __builtin_return_address(0)); } enum aarch64_reloc_op { diff --git a/arch/mips/kernel/module.c b/arch/mips/kernel/module.c index 2a52568..1833f51 100644 --- a/arch/mips/kernel/module.c +++ b/arch/mips/kernel/module.c @@ -47,7 +47,7 @@ static DEFINE_SPINLOCK(dbe_lock); void *module_alloc(unsigned long size) { return __vmalloc_node_range(size, 1, MODULE_START, MODULE_END, - GFP_KERNEL, PAGE_KERNEL, NUMA_NO_NODE, + GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE, __builtin_return_address(0)); } #endif diff --git a/arch/parisc/kernel/module.c b/arch/parisc/kernel/module.c index 5822e8e..3c63a82 100644 --- a/arch/parisc/kernel/module.c +++ b/arch/parisc/kernel/module.c @@ -219,7 +219,7 @@ void *module_alloc(unsigned long size) * init_data correctly */ return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END, GFP_KERNEL | __GFP_HIGHMEM, - PAGE_KERNEL_RWX, NUMA_NO_NODE, + PAGE_KERNEL_RWX, 0, NUMA_NO_NODE, __builtin_return_address(0)); } diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c index 409d152..36154a2 100644 --- a/arch/s390/kernel/module.c +++ b/arch/s390/kernel/module.c @@ -50,7 +50,7 @@ void *module_alloc(unsigned long size) if (PAGE_ALIGN(size) > MODULES_LEN) return NULL; return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, - GFP_KERNEL, PAGE_KERNEL, NUMA_NO_NODE, + GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE, __builtin_return_address(0)); } #endif diff --git a/arch/sparc/kernel/module.c b/arch/sparc/kernel/module.c index 97655e0..192a617 100644 --- a/arch/sparc/kernel/module.c +++ b/arch/sparc/kernel/module.c @@ -29,7 +29,7 @@ static void *module_map(unsigned long size) if (PAGE_ALIGN(size) > MODULES_LEN) return NULL; return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, - GFP_KERNEL, PAGE_KERNEL, NUMA_NO_NODE, + GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE, __builtin_return_address(0)); } #else diff --git a/arch/unicore32/kernel/module.c b/arch/unicore32/kernel/module.c index dc41f6d..e191b34 100644 --- a/arch/unicore32/kernel/module.c +++ b/arch/unicore32/kernel/module.c @@ -25,7 +25,7 @@ void *module_alloc(unsigned long size) { return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, - GFP_KERNEL, PAGE_KERNEL_EXEC, NUMA_NO_NODE, + GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE, __builtin_return_address(0)); } diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c index e69f988..e830e61 100644 --- a/arch/x86/kernel/module.c +++ b/arch/x86/kernel/module.c @@ -88,7 +88,7 @@ void *module_alloc(unsigned long size) return __vmalloc_node_range(size, 1, MODULES_VADDR + get_module_load_offset(), MODULES_END, GFP_KERNEL | __GFP_HIGHMEM, - PAGE_KERNEL_EXEC, NUMA_NO_NODE, + PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE, __builtin_return_address(0)); } diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index 1526fe7..7d7acb3 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -76,7 +76,9 @@ extern void *vmalloc_32_user(unsigned long size); extern void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot); extern void *__vmalloc_node_range(unsigned long size, unsigned long align, unsigned long start, unsigned long end, gfp_t gfp_mask, - pgprot_t prot, int node, const void *caller); + pgprot_t prot, unsigned long vm_flags, int node, + const void *caller); + extern void vfree(const void *addr); extern void *vmap(struct page **pages, unsigned int count, diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 2e74e99..35b25e1 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1619,6 +1619,7 @@ fail: * @end: vm area range end * @gfp_mask: flags for the page level allocator * @prot: protection mask for the allocated pages + * @vm_flags: additional vm area flags (e.g. %VM_NO_GUARD) * @node: node to use for allocation or NUMA_NO_NODE * @caller: caller's return address * @@ -1628,7 +1629,8 @@ fail: */ void *__vmalloc_node_range(unsigned long size, unsigned long align, unsigned long start, unsigned long end, gfp_t gfp_mask, - pgprot_t prot, int node, const void *caller) + pgprot_t prot, unsigned long vm_flags, int node, + const void *caller) { struct vm_struct *area; void *addr; @@ -1638,8 +1640,8 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align, if (!size || (size >> PAGE_SHIFT) > totalram_pages) goto fail; - area = __get_vm_area_node(size, align, VM_ALLOC | VM_UNINITIALIZED, - start, end, node, gfp_mask, caller); + area = __get_vm_area_node(size, align, VM_ALLOC | VM_UNINITIALIZED | + vm_flags, start, end, node, gfp_mask, caller); if (!area) goto fail; @@ -1688,7 +1690,7 @@ static void *__vmalloc_node(unsigned long size, unsigned long align, int node, const void *caller) { return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END, - gfp_mask, prot, node, caller); + gfp_mask, prot, 0, node, caller); } void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot) -- 2.2.2