diff options
Diffstat (limited to 'drivers/misc/lkdtm')
| -rw-r--r-- | drivers/misc/lkdtm/bugs.c | 5 | ||||
| -rw-r--r-- | drivers/misc/lkdtm/core.c | 22 | ||||
| -rw-r--r-- | drivers/misc/lkdtm/heap.c | 2 |
3 files changed, 18 insertions, 11 deletions
diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c index b080eb2335..5178c02b21 100644 --- a/drivers/misc/lkdtm/bugs.c +++ b/drivers/misc/lkdtm/bugs.c @@ -294,10 +294,11 @@ static void lkdtm_SPINLOCKUP(void) __release(&lock_me_up); } -static void lkdtm_HUNG_TASK(void) +static void __noreturn lkdtm_HUNG_TASK(void) { set_current_state(TASK_UNINTERRUPTIBLE); schedule(); + BUG(); } static volatile unsigned int huge = INT_MAX - 2; @@ -416,7 +417,7 @@ static void lkdtm_FAM_BOUNDS(void) pr_err("FAIL: survived access of invalid flexible array member index!\n"); if (!__has_attribute(__counted_by__)) - pr_warn("This is expected since this %s was built a compiler supporting __counted_by\n", + pr_warn("This is expected since this %s was built with a compiler that does not support __counted_by\n", lkdtm_kernel_info); else if (IS_ENABLED(CONFIG_UBSAN_BOUNDS)) pr_expected_config(CONFIG_UBSAN_TRAP); diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c index 0772e4a475..5732fd59a2 100644 --- a/drivers/misc/lkdtm/core.c +++ b/drivers/misc/lkdtm/core.c @@ -153,12 +153,17 @@ static const struct crashtype *find_crashtype(const char *name) /* * This is forced noinline just so it distinctly shows up in the stackdump * which makes validation of expected lkdtm crashes easier. + * + * NOTE: having a valid return value helps prevent the compiler from doing + * tail call optimizations and taking this out of the stack trace. */ -static noinline void lkdtm_do_action(const struct crashtype *crashtype) +static noinline int lkdtm_do_action(const struct crashtype *crashtype) { if (WARN_ON(!crashtype || !crashtype->func)) - return; + return -EINVAL; crashtype->func(); + + return 0; } static int lkdtm_register_cpoint(struct crashpoint *crashpoint, @@ -167,10 +172,8 @@ static int lkdtm_register_cpoint(struct crashpoint *crashpoint, int ret; /* If this doesn't have a symbol, just call immediately. */ - if (!crashpoint->kprobe.symbol_name) { - lkdtm_do_action(crashtype); - return 0; - } + if (!crashpoint->kprobe.symbol_name) + return lkdtm_do_action(crashtype); if (lkdtm_kprobe != NULL) unregister_kprobe(lkdtm_kprobe); @@ -216,7 +219,7 @@ static int lkdtm_kprobe_handler(struct kprobe *kp, struct pt_regs *regs) spin_unlock_irqrestore(&crash_count_lock, flags); if (do_it) - lkdtm_do_action(lkdtm_crashtype); + return lkdtm_do_action(lkdtm_crashtype); return 0; } @@ -303,6 +306,7 @@ static ssize_t direct_entry(struct file *f, const char __user *user_buf, { const struct crashtype *crashtype; char *buf; + int err; if (count >= PAGE_SIZE) return -EINVAL; @@ -326,9 +330,11 @@ static ssize_t direct_entry(struct file *f, const char __user *user_buf, return -EINVAL; pr_info("Performing direct entry %s\n", crashtype->name); - lkdtm_do_action(crashtype); + err = lkdtm_do_action(crashtype); *off += count; + if (err) + return err; return count; } diff --git a/drivers/misc/lkdtm/heap.c b/drivers/misc/lkdtm/heap.c index 4f467d3972..b1b316f997 100644 --- a/drivers/misc/lkdtm/heap.c +++ b/drivers/misc/lkdtm/heap.c @@ -48,7 +48,7 @@ static void lkdtm_VMALLOC_LINEAR_OVERFLOW(void) * correctly. * * This should get caught by either memory tagging, KASan, or by using - * CONFIG_SLUB_DEBUG=y and slub_debug=ZF (or CONFIG_SLUB_DEBUG_ON=y). + * CONFIG_SLUB_DEBUG=y and slab_debug=ZF (or CONFIG_SLUB_DEBUG_ON=y). */ static void lkdtm_SLAB_LINEAR_OVERFLOW(void) { |