diff options
Diffstat (limited to 'drivers/misc')
| -rw-r--r-- | drivers/misc/lkdtm_core.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/drivers/misc/lkdtm_core.c b/drivers/misc/lkdtm_core.c index a595a6f2615a..c915961c4df2 100644 --- a/drivers/misc/lkdtm_core.c +++ b/drivers/misc/lkdtm_core.c @@ -120,6 +120,7 @@ enum ctype { CT_USERCOPY_STACK_FRAME_TO, CT_USERCOPY_STACK_FRAME_FROM, CT_USERCOPY_STACK_BEYOND, + CT_USERCOPY_KERNEL, }; static char* cp_name[] = { @@ -171,6 +172,7 @@ static char* cp_type[] = { "USERCOPY_STACK_FRAME_TO", "USERCOPY_STACK_FRAME_FROM", "USERCOPY_STACK_BEYOND", + "USERCOPY_KERNEL", }; static struct jprobe lkdtm; @@ -495,6 +497,35 @@ free_user: vm_munmap(user_addr, PAGE_SIZE); } +static void do_usercopy_kernel(void) +{ + unsigned long user_addr; + + user_addr = vm_mmap(NULL, 0, PAGE_SIZE, + PROT_READ | PROT_WRITE | PROT_EXEC, + MAP_ANONYMOUS | MAP_PRIVATE, 0); + if (user_addr >= TASK_SIZE) { + pr_warn("Failed to allocate user memory\n"); + return; + } + + pr_info("attempting good copy_to_user from kernel rodata\n"); + if (copy_to_user((void __user *)user_addr, test_text, + sizeof(test_text))) { + pr_warn("copy_to_user failed unexpectedly?!\n"); + goto free_user; + } + + pr_info("attempting bad copy_to_user from kernel text\n"); + if (copy_to_user((void __user *)user_addr, vm_mmap, PAGE_SIZE)) { + pr_warn("copy_to_user failed, but lacked Oops\n"); + goto free_user; + } + +free_user: + vm_munmap(user_addr, PAGE_SIZE); +} + static void do_usercopy_heap_size(bool to_user) { unsigned long user_addr; @@ -957,6 +988,9 @@ static void lkdtm_do_action(enum ctype which) case CT_USERCOPY_STACK_BEYOND: do_usercopy_stack(true, false); break; + case CT_USERCOPY_KERNEL: + do_usercopy_kernel(); + break; case CT_NONE: default: break; |