From: Jeff Xu <[email protected]> Seal PROT and PKEY of the address range, in other words, mprotect() and pkey_mprotect() will be denied if the memory is sealed with MM_SEAL_PROT_PKEY.
Signed-off-by: Jeff Xu <[email protected]> --- mm/mprotect.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/mm/mprotect.c b/mm/mprotect.c index b94fbb45d5c7..1527188b1e92 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -32,6 +32,7 @@ #include <linux/sched/sysctl.h> #include <linux/userfaultfd_k.h> #include <linux/memory-tiers.h> +#include <uapi/linux/mman.h> #include <asm/cacheflush.h> #include <asm/mmu_context.h> #include <asm/tlbflush.h> @@ -753,6 +754,15 @@ static int do_mprotect_pkey(unsigned long start, size_t len, } } + /* + * checking if PROT and PKEY is sealed. + * can_modify_mm assumes we have acquired the lock on MM. + */ + if (!can_modify_mm(current->mm, start, end, MM_SEAL_PROT_PKEY)) { + error = -EACCES; + goto out; + } + prev = vma_prev(&vmi); if (start > vma->vm_start) prev = vma; -- 2.43.0.472.g3155946c3a-goog
