Commit-ID: ff86b30010eee8249dc244ce1868b886bbee6449 Gitweb: http://git.kernel.org/tip/ff86b30010eee8249dc244ce1868b886bbee6449 Author: Kees Cook <keesc...@chromium.org> AuthorDate: Fri, 3 Feb 2017 15:26:50 -0800 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Fri, 10 Feb 2017 09:04:20 +0100
lkdtm: Convert to refcount_t testing Since we'll be using refcount_t instead of atomic_t for refcounting, change the LKDTM tests to reflect the new interface and test conditions. Signed-off-by: Kees Cook <keesc...@chromium.org> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Hans Liljestrand <ishkam...@gmail.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: a...@arndb.de Cc: dhowe...@redhat.com Cc: dwind...@gmail.com Cc: elena.reshet...@intel.com Cc: gre...@linuxfoundation.org Cc: h.peter.an...@intel.com Cc: kernel-harden...@lists.openwall.com Cc: will.dea...@arm.com Link: http://lkml.kernel.org/r/1486164412-7338-3-git-send-email-keesc...@chromium.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- drivers/misc/lkdtm.h | 8 +++-- drivers/misc/lkdtm_bugs.c | 87 +++++++++++++++++++++++++++++++++++++++-------- drivers/misc/lkdtm_core.c | 8 +++-- 3 files changed, 85 insertions(+), 18 deletions(-) diff --git a/drivers/misc/lkdtm.h b/drivers/misc/lkdtm.h index cfa1039..67d27be 100644 --- a/drivers/misc/lkdtm.h +++ b/drivers/misc/lkdtm.h @@ -19,8 +19,12 @@ void lkdtm_SOFTLOCKUP(void); void lkdtm_HARDLOCKUP(void); void lkdtm_SPINLOCKUP(void); void lkdtm_HUNG_TASK(void); -void lkdtm_ATOMIC_UNDERFLOW(void); -void lkdtm_ATOMIC_OVERFLOW(void); +void lkdtm_REFCOUNT_SATURATE_INC(void); +void lkdtm_REFCOUNT_SATURATE_ADD(void); +void lkdtm_REFCOUNT_ZERO_DEC(void); +void lkdtm_REFCOUNT_ZERO_INC(void); +void lkdtm_REFCOUNT_ZERO_SUB(void); +void lkdtm_REFCOUNT_ZERO_ADD(void); void lkdtm_CORRUPT_LIST_ADD(void); void lkdtm_CORRUPT_LIST_DEL(void); diff --git a/drivers/misc/lkdtm_bugs.c b/drivers/misc/lkdtm_bugs.c index 91edd0b..cba0837 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) diff --git a/drivers/misc/lkdtm_core.c b/drivers/misc/lkdtm_core.c index 7eeb71a..16e4cf1 100644 --- a/drivers/misc/lkdtm_core.c +++ b/drivers/misc/lkdtm_core.c @@ -220,8 +220,12 @@ struct crashtype crashtypes[] = { CRASHTYPE(WRITE_RO), CRASHTYPE(WRITE_RO_AFTER_INIT), CRASHTYPE(WRITE_KERN), - CRASHTYPE(ATOMIC_UNDERFLOW), - CRASHTYPE(ATOMIC_OVERFLOW), + CRASHTYPE(REFCOUNT_SATURATE_INC), + CRASHTYPE(REFCOUNT_SATURATE_ADD), + CRASHTYPE(REFCOUNT_ZERO_DEC), + CRASHTYPE(REFCOUNT_ZERO_INC), + CRASHTYPE(REFCOUNT_ZERO_SUB), + CRASHTYPE(REFCOUNT_ZERO_ADD), CRASHTYPE(USERCOPY_HEAP_SIZE_TO), CRASHTYPE(USERCOPY_HEAP_SIZE_FROM), CRASHTYPE(USERCOPY_HEAP_FLAG_TO),
