From 8776fe75dc0e263ed2056ea9896c2267599dc447 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 20 Oct 2017 06:31:27 -0700 Subject: [PATCH] lkdtm, kprobes: Convert from jprobes to kprobes The jprobes subsystem is being removed, so convert to using kprobes instead. Signed-off-by: Kees Cook Acked-by: Masami Hiramatsu Cc: Greg Kroah-Hartman Cc: Linus Torvalds Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20171020133127.GA18360@beast Signed-off-by: Ingo Molnar --- drivers/misc/lkdtm_core.c | 154 +++++++++++--------------------------- 1 file changed, 45 insertions(+), 109 deletions(-) diff --git a/drivers/misc/lkdtm_core.c b/drivers/misc/lkdtm_core.c index 981b3ef71e47..ed7f0c61c59a 100644 --- a/drivers/misc/lkdtm_core.c +++ b/drivers/misc/lkdtm_core.c @@ -56,122 +56,54 @@ static ssize_t direct_entry(struct file *f, const char __user *user_buf, size_t count, loff_t *off); #ifdef CONFIG_KPROBES -static void lkdtm_handler(void); +static int lkdtm_kprobe_handler(struct kprobe *kp, struct pt_regs *regs); static ssize_t lkdtm_debugfs_entry(struct file *f, const char __user *user_buf, size_t count, loff_t *off); - - -/* jprobe entry point handlers. */ -static unsigned int jp_do_irq(unsigned int irq) -{ - lkdtm_handler(); - jprobe_return(); - return 0; -} - -static irqreturn_t jp_handle_irq_event(unsigned int irq, - struct irqaction *action) -{ - lkdtm_handler(); - jprobe_return(); - return 0; -} - -static void jp_tasklet_action(struct softirq_action *a) -{ - lkdtm_handler(); - jprobe_return(); -} - -static void jp_ll_rw_block(int rw, int nr, struct buffer_head *bhs[]) -{ - lkdtm_handler(); - jprobe_return(); -} - -struct scan_control; - -static unsigned long jp_shrink_inactive_list(unsigned long max_scan, - struct zone *zone, - struct scan_control *sc) -{ - lkdtm_handler(); - jprobe_return(); - return 0; -} - -static int jp_hrtimer_start(struct hrtimer *timer, ktime_t tim, - const enum hrtimer_mode mode) -{ - lkdtm_handler(); - jprobe_return(); - return 0; -} - -static int jp_scsi_dispatch_cmd(struct scsi_cmnd *cmd) -{ - lkdtm_handler(); - jprobe_return(); - return 0; -} - -# ifdef CONFIG_IDE -static int jp_generic_ide_ioctl(ide_drive_t *drive, struct file *file, - struct block_device *bdev, unsigned int cmd, - unsigned long arg) -{ - lkdtm_handler(); - jprobe_return(); - return 0; -} -# endif +# define CRASHPOINT_KPROBE(_symbol) \ + .kprobe = { \ + .symbol_name = (_symbol), \ + .pre_handler = lkdtm_kprobe_handler, \ + }, +# define CRASHPOINT_WRITE(_symbol) \ + (_symbol) ? lkdtm_debugfs_entry : direct_entry +#else +# define CRASHPOINT_KPROBE(_symbol) +# define CRASHPOINT_WRITE(_symbol) direct_entry #endif /* Crash points */ struct crashpoint { const char *name; const struct file_operations fops; - struct jprobe jprobe; + struct kprobe kprobe; }; -#define CRASHPOINT(_name, _write, _symbol, _entry) \ +#define CRASHPOINT(_name, _symbol) \ { \ .name = _name, \ .fops = { \ .read = lkdtm_debugfs_read, \ .llseek = generic_file_llseek, \ .open = lkdtm_debugfs_open, \ - .write = _write, \ - }, \ - .jprobe = { \ - .kp.symbol_name = _symbol, \ - .entry = (kprobe_opcode_t *)_entry, \ + .write = CRASHPOINT_WRITE(_symbol) \ }, \ + CRASHPOINT_KPROBE(_symbol) \ } /* Define the possible places where we can trigger a crash point. */ -struct crashpoint crashpoints[] = { - CRASHPOINT("DIRECT", direct_entry, - NULL, NULL), +static struct crashpoint crashpoints[] = { + CRASHPOINT("DIRECT", NULL), #ifdef CONFIG_KPROBES - CRASHPOINT("INT_HARDWARE_ENTRY", lkdtm_debugfs_entry, - "do_IRQ", jp_do_irq), - CRASHPOINT("INT_HW_IRQ_EN", lkdtm_debugfs_entry, - "handle_IRQ_event", jp_handle_irq_event), - CRASHPOINT("INT_TASKLET_ENTRY", lkdtm_debugfs_entry, - "tasklet_action", jp_tasklet_action), - CRASHPOINT("FS_DEVRW", lkdtm_debugfs_entry, - "ll_rw_block", jp_ll_rw_block), - CRASHPOINT("MEM_SWAPOUT", lkdtm_debugfs_entry, - "shrink_inactive_list", jp_shrink_inactive_list), - CRASHPOINT("TIMERADD", lkdtm_debugfs_entry, - "hrtimer_start", jp_hrtimer_start), - CRASHPOINT("SCSI_DISPATCH_CMD", lkdtm_debugfs_entry, - "scsi_dispatch_cmd", jp_scsi_dispatch_cmd), + CRASHPOINT("INT_HARDWARE_ENTRY", "do_IRQ"), + CRASHPOINT("INT_HW_IRQ_EN", "handle_IRQ_event"), + CRASHPOINT("INT_TASKLET_ENTRY", "tasklet_action"), + CRASHPOINT("FS_DEVRW", "ll_rw_block"), + CRASHPOINT("MEM_SWAPOUT", "shrink_inactive_list"), + CRASHPOINT("TIMERADD", "hrtimer_start"), + CRASHPOINT("SCSI_DISPATCH_CMD", "scsi_dispatch_cmd"), # ifdef CONFIG_IDE - CRASHPOINT("IDE_CORE_CP", lkdtm_debugfs_entry, - "generic_ide_ioctl", jp_generic_ide_ioctl), + CRASHPOINT("IDE_CORE_CP", "generic_ide_ioctl"), # endif #endif }; @@ -254,8 +186,8 @@ struct crashtype crashtypes[] = { }; -/* Global jprobe entry and crashtype. */ -static struct jprobe *lkdtm_jprobe; +/* Global kprobe entry and crashtype. */ +static struct kprobe *lkdtm_kprobe; struct crashpoint *lkdtm_crashpoint; struct crashtype *lkdtm_crashtype; @@ -298,7 +230,8 @@ static struct crashtype *find_crashtype(const char *name) */ static noinline void lkdtm_do_action(struct crashtype *crashtype) { - BUG_ON(!crashtype || !crashtype->func); + if (WARN_ON(!crashtype || !crashtype->func)) + return; crashtype->func(); } @@ -308,22 +241,22 @@ static int lkdtm_register_cpoint(struct crashpoint *crashpoint, int ret; /* If this doesn't have a symbol, just call immediately. */ - if (!crashpoint->jprobe.kp.symbol_name) { + if (!crashpoint->kprobe.symbol_name) { lkdtm_do_action(crashtype); return 0; } - if (lkdtm_jprobe != NULL) - unregister_jprobe(lkdtm_jprobe); + if (lkdtm_kprobe != NULL) + unregister_kprobe(lkdtm_kprobe); lkdtm_crashpoint = crashpoint; lkdtm_crashtype = crashtype; - lkdtm_jprobe = &crashpoint->jprobe; - ret = register_jprobe(lkdtm_jprobe); + lkdtm_kprobe = &crashpoint->kprobe; + ret = register_kprobe(lkdtm_kprobe); if (ret < 0) { - pr_info("Couldn't register jprobe %s\n", - crashpoint->jprobe.kp.symbol_name); - lkdtm_jprobe = NULL; + pr_info("Couldn't register kprobe %s\n", + crashpoint->kprobe.symbol_name); + lkdtm_kprobe = NULL; lkdtm_crashpoint = NULL; lkdtm_crashtype = NULL; } @@ -336,13 +269,14 @@ static int lkdtm_register_cpoint(struct crashpoint *crashpoint, static int crash_count = DEFAULT_COUNT; static DEFINE_SPINLOCK(crash_count_lock); -/* Called by jprobe entry points. */ -static void lkdtm_handler(void) +/* Called by kprobe entry points. */ +static int lkdtm_kprobe_handler(struct kprobe *kp, struct pt_regs *regs) { unsigned long flags; bool do_it = false; - BUG_ON(!lkdtm_crashpoint || !lkdtm_crashtype); + if (WARN_ON(!lkdtm_crashpoint || !lkdtm_crashtype)) + return 0; spin_lock_irqsave(&crash_count_lock, flags); crash_count--; @@ -357,6 +291,8 @@ static void lkdtm_handler(void) if (do_it) lkdtm_do_action(lkdtm_crashtype); + + return 0; } static ssize_t lkdtm_debugfs_entry(struct file *f, @@ -556,8 +492,8 @@ static void __exit lkdtm_module_exit(void) /* Handle test-specific clean-up. */ lkdtm_usercopy_exit(); - if (lkdtm_jprobe != NULL) - unregister_jprobe(lkdtm_jprobe); + if (lkdtm_kprobe != NULL) + unregister_kprobe(lkdtm_kprobe); pr_info("Crash point unregistered\n"); }