diff options
Diffstat (limited to 'drivers/misc/lkdtm_bugs.c')
| -rw-r--r-- | drivers/misc/lkdtm_bugs.c | 87 |
1 files changed, 73 insertions, 14 deletions
diff --git a/drivers/misc/lkdtm_bugs.c b/drivers/misc/lkdtm_bugs.c index 91edd0b55e5c..cba0837aee2e 100644 --- a/drivers/misc/lkdtm_bugs.c +++ b/drivers/misc/lkdtm_bugs.c @@ -6,6 +6,7 @@ */ #include "lkdtm.h" #include <linux/list.h> +#include <linux/refcount.h> #include <linux/sched.h> struct lkdtm_list { @@ -129,28 +130,86 @@ void lkdtm_HUNG_TASK(void) schedule(); } -void lkdtm_ATOMIC_UNDERFLOW(void) +void lkdtm_REFCOUNT_SATURATE_INC(void) { - atomic_t under = ATOMIC_INIT(INT_MIN); + refcount_t over = REFCOUNT_INIT(UINT_MAX - 1); - pr_info("attempting good atomic increment\n"); - atomic_inc(&under); - atomic_dec(&under); + pr_info("attempting good refcount decrement\n"); + refcount_dec(&over); + refcount_inc(&over); - pr_info("attempting bad atomic underflow\n"); - atomic_dec(&under); + pr_info("attempting bad refcount inc overflow\n"); + refcount_inc(&over); + refcount_inc(&over); + if (refcount_read(&over) == UINT_MAX) + pr_err("Correctly stayed saturated, but no BUG?!\n"); + else + pr_err("Fail: refcount wrapped\n"); +} + +void lkdtm_REFCOUNT_SATURATE_ADD(void) +{ + refcount_t over = REFCOUNT_INIT(UINT_MAX - 1); + + pr_info("attempting good refcount decrement\n"); + refcount_dec(&over); + refcount_inc(&over); + + pr_info("attempting bad refcount add overflow\n"); + refcount_add(2, &over); + if (refcount_read(&over) == UINT_MAX) + pr_err("Correctly stayed saturated, but no BUG?!\n"); + else + pr_err("Fail: refcount wrapped\n"); +} + +void lkdtm_REFCOUNT_ZERO_DEC(void) +{ + refcount_t zero = REFCOUNT_INIT(1); + + pr_info("attempting bad refcount decrement to zero\n"); + refcount_dec(&zero); + if (refcount_read(&zero) == 0) + pr_err("Stayed at zero, but no BUG?!\n"); + else + pr_err("Fail: refcount went crazy\n"); } -void lkdtm_ATOMIC_OVERFLOW(void) +void lkdtm_REFCOUNT_ZERO_SUB(void) { - atomic_t over = ATOMIC_INIT(INT_MAX); + refcount_t zero = REFCOUNT_INIT(1); + + pr_info("attempting bad refcount subtract past zero\n"); + if (!refcount_sub_and_test(2, &zero)) + pr_info("wrap attempt was noticed\n"); + if (refcount_read(&zero) == 1) + pr_err("Correctly stayed above 0, but no BUG?!\n"); + else + pr_err("Fail: refcount wrapped\n"); +} - pr_info("attempting good atomic decrement\n"); - atomic_dec(&over); - atomic_inc(&over); +void lkdtm_REFCOUNT_ZERO_INC(void) +{ + refcount_t zero = REFCOUNT_INIT(0); - pr_info("attempting bad atomic overflow\n"); - atomic_inc(&over); + pr_info("attempting bad refcount increment from zero\n"); + refcount_inc(&zero); + if (refcount_read(&zero) == 0) + pr_err("Stayed at zero, but no BUG?!\n"); + else + pr_err("Fail: refcount went past zero\n"); +} + +void lkdtm_REFCOUNT_ZERO_ADD(void) +{ + refcount_t zero = REFCOUNT_INIT(0); + + pr_info("attempting bad refcount addition from zero\n"); + refcount_add(2, &zero); + if (refcount_read(&zero) == 0) + pr_err("Stayed at zero, but no BUG?!\n"); + else + pr_err("Fail: refcount went past zero\n"); } void lkdtm_CORRUPT_LIST_ADD(void) |