kprobes: Allow probe on some kprobe functions
There is no need to prohibit probing on the functions
used for preparation, registeration, optimization,
controll etc. Those are safely probed because those are
not invoked from breakpoint/fault/debug handlers,
there is no chance to cause recursive exceptions.
Following functions are now removed from the kprobes blacklist:
add_new_kprobe
aggr_kprobe_disabled
alloc_aggr_kprobe
alloc_aggr_kprobe
arm_all_kprobes
__arm_kprobe
arm_kprobe
arm_kprobe_ftrace
check_kprobe_address_safe
collect_garbage_slots
collect_garbage_slots
collect_one_slot
debugfs_kprobe_init
__disable_kprobe
disable_kprobe
disarm_all_kprobes
__disarm_kprobe
disarm_kprobe
disarm_kprobe_ftrace
do_free_cleaned_kprobes
do_optimize_kprobes
do_unoptimize_kprobes
enable_kprobe
force_unoptimize_kprobe
free_aggr_kprobe
free_aggr_kprobe
__free_insn_slot
__get_insn_slot
get_optimized_kprobe
__get_valid_kprobe
init_aggr_kprobe
init_aggr_kprobe
in_nokprobe_functions
kick_kprobe_optimizer
kill_kprobe
kill_optimized_kprobe
kprobe_addr
kprobe_optimizer
kprobe_queued
kprobe_seq_next
kprobe_seq_start
kprobe_seq_stop
kprobes_module_callback
kprobes_open
optimize_all_kprobes
optimize_kprobe
prepare_kprobe
prepare_optimized_kprobe
register_aggr_kprobe
register_jprobe
register_jprobes
register_kprobe
register_kprobes
register_kretprobe
register_kretprobe
register_kretprobes
register_kretprobes
report_probe
show_kprobe_addr
try_to_optimize_kprobe
unoptimize_all_kprobes
unoptimize_kprobe
unregister_jprobe
unregister_jprobes
unregister_kprobe
__unregister_kprobe_bottom
unregister_kprobes
__unregister_kprobe_top
unregister_kretprobe
unregister_kretprobe
unregister_kretprobes
unregister_kretprobes
wait_for_kprobe_optimizer
I tested those functions by putting kprobes on all
instructions in the functions with the bash script
I sent to LKML. See:
https://lkml.org/lkml/2014/3/27/33
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Link: http://lkml.kernel.org/r/20140417081753.26341.57889.stgit@ltc230.yrl.intra.hitachi.co.jp
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: fche@redhat.com
Cc: systemtap@sourceware.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 5ffc687..4db2cc6 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -138,13 +138,13 @@
.insn_size = MAX_INSN_SIZE,
.nr_garbage = 0,
};
-static int __kprobes collect_garbage_slots(struct kprobe_insn_cache *c);
+static int collect_garbage_slots(struct kprobe_insn_cache *c);
/**
* __get_insn_slot() - Find a slot on an executable page for an instruction.
* We allocate an executable page if there's no room on existing ones.
*/
-kprobe_opcode_t __kprobes *__get_insn_slot(struct kprobe_insn_cache *c)
+kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c)
{
struct kprobe_insn_page *kip;
kprobe_opcode_t *slot = NULL;
@@ -201,7 +201,7 @@
}
/* Return 1 if all garbages are collected, otherwise 0. */
-static int __kprobes collect_one_slot(struct kprobe_insn_page *kip, int idx)
+static int collect_one_slot(struct kprobe_insn_page *kip, int idx)
{
kip->slot_used[idx] = SLOT_CLEAN;
kip->nused--;
@@ -222,7 +222,7 @@
return 0;
}
-static int __kprobes collect_garbage_slots(struct kprobe_insn_cache *c)
+static int collect_garbage_slots(struct kprobe_insn_cache *c)
{
struct kprobe_insn_page *kip, *next;
@@ -244,8 +244,8 @@
return 0;
}
-void __kprobes __free_insn_slot(struct kprobe_insn_cache *c,
- kprobe_opcode_t *slot, int dirty)
+void __free_insn_slot(struct kprobe_insn_cache *c,
+ kprobe_opcode_t *slot, int dirty)
{
struct kprobe_insn_page *kip;
@@ -361,7 +361,7 @@
}
/* Free optimized instructions and optimized_kprobe */
-static __kprobes void free_aggr_kprobe(struct kprobe *p)
+static void free_aggr_kprobe(struct kprobe *p)
{
struct optimized_kprobe *op;
@@ -399,7 +399,7 @@
}
/* Return true(!0) if the probe is queued on (un)optimizing lists */
-static int __kprobes kprobe_queued(struct kprobe *p)
+static int kprobe_queued(struct kprobe *p)
{
struct optimized_kprobe *op;
@@ -415,7 +415,7 @@
* Return an optimized kprobe whose optimizing code replaces
* instructions including addr (exclude breakpoint).
*/
-static struct kprobe *__kprobes get_optimized_kprobe(unsigned long addr)
+static struct kprobe *get_optimized_kprobe(unsigned long addr)
{
int i;
struct kprobe *p = NULL;
@@ -447,7 +447,7 @@
* Optimize (replace a breakpoint with a jump) kprobes listed on
* optimizing_list.
*/
-static __kprobes void do_optimize_kprobes(void)
+static void do_optimize_kprobes(void)
{
/* Optimization never be done when disarmed */
if (kprobes_all_disarmed || !kprobes_allow_optimization ||
@@ -475,7 +475,7 @@
* Unoptimize (replace a jump with a breakpoint and remove the breakpoint
* if need) kprobes listed on unoptimizing_list.
*/
-static __kprobes void do_unoptimize_kprobes(void)
+static void do_unoptimize_kprobes(void)
{
struct optimized_kprobe *op, *tmp;
@@ -507,7 +507,7 @@
}
/* Reclaim all kprobes on the free_list */
-static __kprobes void do_free_cleaned_kprobes(void)
+static void do_free_cleaned_kprobes(void)
{
struct optimized_kprobe *op, *tmp;
@@ -519,13 +519,13 @@
}
/* Start optimizer after OPTIMIZE_DELAY passed */
-static __kprobes void kick_kprobe_optimizer(void)
+static void kick_kprobe_optimizer(void)
{
schedule_delayed_work(&optimizing_work, OPTIMIZE_DELAY);
}
/* Kprobe jump optimizer */
-static __kprobes void kprobe_optimizer(struct work_struct *work)
+static void kprobe_optimizer(struct work_struct *work)
{
mutex_lock(&kprobe_mutex);
/* Lock modules while optimizing kprobes */
@@ -561,7 +561,7 @@
}
/* Wait for completing optimization and unoptimization */
-static __kprobes void wait_for_kprobe_optimizer(void)
+static void wait_for_kprobe_optimizer(void)
{
mutex_lock(&kprobe_mutex);
@@ -580,7 +580,7 @@
}
/* Optimize kprobe if p is ready to be optimized */
-static __kprobes void optimize_kprobe(struct kprobe *p)
+static void optimize_kprobe(struct kprobe *p)
{
struct optimized_kprobe *op;
@@ -614,7 +614,7 @@
}
/* Short cut to direct unoptimizing */
-static __kprobes void force_unoptimize_kprobe(struct optimized_kprobe *op)
+static void force_unoptimize_kprobe(struct optimized_kprobe *op)
{
get_online_cpus();
arch_unoptimize_kprobe(op);
@@ -624,7 +624,7 @@
}
/* Unoptimize a kprobe if p is optimized */
-static __kprobes void unoptimize_kprobe(struct kprobe *p, bool force)
+static void unoptimize_kprobe(struct kprobe *p, bool force)
{
struct optimized_kprobe *op;
@@ -684,7 +684,7 @@
}
/* Remove optimized instructions */
-static void __kprobes kill_optimized_kprobe(struct kprobe *p)
+static void kill_optimized_kprobe(struct kprobe *p)
{
struct optimized_kprobe *op;
@@ -710,7 +710,7 @@
}
/* Try to prepare optimized instructions */
-static __kprobes void prepare_optimized_kprobe(struct kprobe *p)
+static void prepare_optimized_kprobe(struct kprobe *p)
{
struct optimized_kprobe *op;
@@ -719,7 +719,7 @@
}
/* Allocate new optimized_kprobe and try to prepare optimized instructions */
-static __kprobes struct kprobe *alloc_aggr_kprobe(struct kprobe *p)
+static struct kprobe *alloc_aggr_kprobe(struct kprobe *p)
{
struct optimized_kprobe *op;
@@ -734,13 +734,13 @@
return &op->kp;
}
-static void __kprobes init_aggr_kprobe(struct kprobe *ap, struct kprobe *p);
+static void init_aggr_kprobe(struct kprobe *ap, struct kprobe *p);
/*
* Prepare an optimized_kprobe and optimize it
* NOTE: p must be a normal registered kprobe
*/
-static __kprobes void try_to_optimize_kprobe(struct kprobe *p)
+static void try_to_optimize_kprobe(struct kprobe *p)
{
struct kprobe *ap;
struct optimized_kprobe *op;
@@ -774,7 +774,7 @@
}
#ifdef CONFIG_SYSCTL
-static void __kprobes optimize_all_kprobes(void)
+static void optimize_all_kprobes(void)
{
struct hlist_head *head;
struct kprobe *p;
@@ -797,7 +797,7 @@
mutex_unlock(&kprobe_mutex);
}
-static void __kprobes unoptimize_all_kprobes(void)
+static void unoptimize_all_kprobes(void)
{
struct hlist_head *head;
struct kprobe *p;
@@ -848,7 +848,7 @@
#endif /* CONFIG_SYSCTL */
/* Put a breakpoint for a probe. Must be called with text_mutex locked */
-static void __kprobes __arm_kprobe(struct kprobe *p)
+static void __arm_kprobe(struct kprobe *p)
{
struct kprobe *_p;
@@ -863,7 +863,7 @@
}
/* Remove the breakpoint of a probe. Must be called with text_mutex locked */
-static void __kprobes __disarm_kprobe(struct kprobe *p, bool reopt)
+static void __disarm_kprobe(struct kprobe *p, bool reopt)
{
struct kprobe *_p;
@@ -898,13 +898,13 @@
BUG_ON(kprobe_unused(ap));
}
-static __kprobes void free_aggr_kprobe(struct kprobe *p)
+static void free_aggr_kprobe(struct kprobe *p)
{
arch_remove_kprobe(p);
kfree(p);
}
-static __kprobes struct kprobe *alloc_aggr_kprobe(struct kprobe *p)
+static struct kprobe *alloc_aggr_kprobe(struct kprobe *p)
{
return kzalloc(sizeof(struct kprobe), GFP_KERNEL);
}
@@ -918,7 +918,7 @@
static int kprobe_ftrace_enabled;
/* Must ensure p->addr is really on ftrace */
-static int __kprobes prepare_kprobe(struct kprobe *p)
+static int prepare_kprobe(struct kprobe *p)
{
if (!kprobe_ftrace(p))
return arch_prepare_kprobe(p);
@@ -927,7 +927,7 @@
}
/* Caller must lock kprobe_mutex */
-static void __kprobes arm_kprobe_ftrace(struct kprobe *p)
+static void arm_kprobe_ftrace(struct kprobe *p)
{
int ret;
@@ -942,7 +942,7 @@
}
/* Caller must lock kprobe_mutex */
-static void __kprobes disarm_kprobe_ftrace(struct kprobe *p)
+static void disarm_kprobe_ftrace(struct kprobe *p)
{
int ret;
@@ -962,7 +962,7 @@
#endif
/* Arm a kprobe with text_mutex */
-static void __kprobes arm_kprobe(struct kprobe *kp)
+static void arm_kprobe(struct kprobe *kp)
{
if (unlikely(kprobe_ftrace(kp))) {
arm_kprobe_ftrace(kp);
@@ -979,7 +979,7 @@
}
/* Disarm a kprobe with text_mutex */
-static void __kprobes disarm_kprobe(struct kprobe *kp, bool reopt)
+static void disarm_kprobe(struct kprobe *kp, bool reopt)
{
if (unlikely(kprobe_ftrace(kp))) {
disarm_kprobe_ftrace(kp);
@@ -1189,7 +1189,7 @@
* Add the new probe to ap->list. Fail if this is the
* second jprobe at the address - two jprobes can't coexist
*/
-static int __kprobes add_new_kprobe(struct kprobe *ap, struct kprobe *p)
+static int add_new_kprobe(struct kprobe *ap, struct kprobe *p)
{
BUG_ON(kprobe_gone(ap) || kprobe_gone(p));
@@ -1213,7 +1213,7 @@
* Fill in the required fields of the "manager kprobe". Replace the
* earlier kprobe in the hlist with the manager kprobe
*/
-static void __kprobes init_aggr_kprobe(struct kprobe *ap, struct kprobe *p)
+static void init_aggr_kprobe(struct kprobe *ap, struct kprobe *p)
{
/* Copy p's insn slot to ap */
copy_kprobe(p, ap);
@@ -1239,8 +1239,7 @@
* This is the second or subsequent kprobe at the address - handle
* the intricacies
*/
-static int __kprobes register_aggr_kprobe(struct kprobe *orig_p,
- struct kprobe *p)
+static int register_aggr_kprobe(struct kprobe *orig_p, struct kprobe *p)
{
int ret = 0;
struct kprobe *ap = orig_p;
@@ -1318,7 +1317,7 @@
addr < (unsigned long)__kprobes_text_end;
}
-static bool __kprobes within_kprobe_blacklist(unsigned long addr)
+static bool within_kprobe_blacklist(unsigned long addr)
{
struct kprobe_blacklist_entry *ent;
@@ -1342,7 +1341,7 @@
* This returns encoded errors if it fails to look up symbol or invalid
* combination of parameters.
*/
-static kprobe_opcode_t __kprobes *kprobe_addr(struct kprobe *p)
+static kprobe_opcode_t *kprobe_addr(struct kprobe *p)
{
kprobe_opcode_t *addr = p->addr;
@@ -1365,7 +1364,7 @@
}
/* Check passed kprobe is valid and return kprobe in kprobe_table. */
-static struct kprobe * __kprobes __get_valid_kprobe(struct kprobe *p)
+static struct kprobe *__get_valid_kprobe(struct kprobe *p)
{
struct kprobe *ap, *list_p;
@@ -1397,8 +1396,8 @@
return ret;
}
-static __kprobes int check_kprobe_address_safe(struct kprobe *p,
- struct module **probed_mod)
+static int check_kprobe_address_safe(struct kprobe *p,
+ struct module **probed_mod)
{
int ret = 0;
unsigned long ftrace_addr;
@@ -1460,7 +1459,7 @@
return ret;
}
-int __kprobes register_kprobe(struct kprobe *p)
+int register_kprobe(struct kprobe *p)
{
int ret;
struct kprobe *old_p;
@@ -1522,7 +1521,7 @@
EXPORT_SYMBOL_GPL(register_kprobe);
/* Check if all probes on the aggrprobe are disabled */
-static int __kprobes aggr_kprobe_disabled(struct kprobe *ap)
+static int aggr_kprobe_disabled(struct kprobe *ap)
{
struct kprobe *kp;
@@ -1538,7 +1537,7 @@
}
/* Disable one kprobe: Make sure called under kprobe_mutex is locked */
-static struct kprobe *__kprobes __disable_kprobe(struct kprobe *p)
+static struct kprobe *__disable_kprobe(struct kprobe *p)
{
struct kprobe *orig_p;
@@ -1565,7 +1564,7 @@
/*
* Unregister a kprobe without a scheduler synchronization.
*/
-static int __kprobes __unregister_kprobe_top(struct kprobe *p)
+static int __unregister_kprobe_top(struct kprobe *p)
{
struct kprobe *ap, *list_p;
@@ -1622,7 +1621,7 @@
return 0;
}
-static void __kprobes __unregister_kprobe_bottom(struct kprobe *p)
+static void __unregister_kprobe_bottom(struct kprobe *p)
{
struct kprobe *ap;
@@ -1638,7 +1637,7 @@
/* Otherwise, do nothing. */
}
-int __kprobes register_kprobes(struct kprobe **kps, int num)
+int register_kprobes(struct kprobe **kps, int num)
{
int i, ret = 0;
@@ -1656,13 +1655,13 @@
}
EXPORT_SYMBOL_GPL(register_kprobes);
-void __kprobes unregister_kprobe(struct kprobe *p)
+void unregister_kprobe(struct kprobe *p)
{
unregister_kprobes(&p, 1);
}
EXPORT_SYMBOL_GPL(unregister_kprobe);
-void __kprobes unregister_kprobes(struct kprobe **kps, int num)
+void unregister_kprobes(struct kprobe **kps, int num)
{
int i;
@@ -1691,7 +1690,7 @@
return (unsigned long)entry;
}
-int __kprobes register_jprobes(struct jprobe **jps, int num)
+int register_jprobes(struct jprobe **jps, int num)
{
struct jprobe *jp;
int ret = 0, i;
@@ -1722,19 +1721,19 @@
}
EXPORT_SYMBOL_GPL(register_jprobes);
-int __kprobes register_jprobe(struct jprobe *jp)
+int register_jprobe(struct jprobe *jp)
{
return register_jprobes(&jp, 1);
}
EXPORT_SYMBOL_GPL(register_jprobe);
-void __kprobes unregister_jprobe(struct jprobe *jp)
+void unregister_jprobe(struct jprobe *jp)
{
unregister_jprobes(&jp, 1);
}
EXPORT_SYMBOL_GPL(unregister_jprobe);
-void __kprobes unregister_jprobes(struct jprobe **jps, int num)
+void unregister_jprobes(struct jprobe **jps, int num)
{
int i;
@@ -1799,7 +1798,7 @@
return 0;
}
-int __kprobes register_kretprobe(struct kretprobe *rp)
+int register_kretprobe(struct kretprobe *rp)
{
int ret = 0;
struct kretprobe_instance *inst;
@@ -1852,7 +1851,7 @@
}
EXPORT_SYMBOL_GPL(register_kretprobe);
-int __kprobes register_kretprobes(struct kretprobe **rps, int num)
+int register_kretprobes(struct kretprobe **rps, int num)
{
int ret = 0, i;
@@ -1870,13 +1869,13 @@
}
EXPORT_SYMBOL_GPL(register_kretprobes);
-void __kprobes unregister_kretprobe(struct kretprobe *rp)
+void unregister_kretprobe(struct kretprobe *rp)
{
unregister_kretprobes(&rp, 1);
}
EXPORT_SYMBOL_GPL(unregister_kretprobe);
-void __kprobes unregister_kretprobes(struct kretprobe **rps, int num)
+void unregister_kretprobes(struct kretprobe **rps, int num)
{
int i;
@@ -1899,24 +1898,24 @@
EXPORT_SYMBOL_GPL(unregister_kretprobes);
#else /* CONFIG_KRETPROBES */
-int __kprobes register_kretprobe(struct kretprobe *rp)
+int register_kretprobe(struct kretprobe *rp)
{
return -ENOSYS;
}
EXPORT_SYMBOL_GPL(register_kretprobe);
-int __kprobes register_kretprobes(struct kretprobe **rps, int num)
+int register_kretprobes(struct kretprobe **rps, int num)
{
return -ENOSYS;
}
EXPORT_SYMBOL_GPL(register_kretprobes);
-void __kprobes unregister_kretprobe(struct kretprobe *rp)
+void unregister_kretprobe(struct kretprobe *rp)
{
}
EXPORT_SYMBOL_GPL(unregister_kretprobe);
-void __kprobes unregister_kretprobes(struct kretprobe **rps, int num)
+void unregister_kretprobes(struct kretprobe **rps, int num)
{
}
EXPORT_SYMBOL_GPL(unregister_kretprobes);
@@ -1930,7 +1929,7 @@
#endif /* CONFIG_KRETPROBES */
/* Set the kprobe gone and remove its instruction buffer. */
-static void __kprobes kill_kprobe(struct kprobe *p)
+static void kill_kprobe(struct kprobe *p)
{
struct kprobe *kp;
@@ -1954,7 +1953,7 @@
}
/* Disable one kprobe */
-int __kprobes disable_kprobe(struct kprobe *kp)
+int disable_kprobe(struct kprobe *kp)
{
int ret = 0;
@@ -1970,7 +1969,7 @@
EXPORT_SYMBOL_GPL(disable_kprobe);
/* Enable one kprobe */
-int __kprobes enable_kprobe(struct kprobe *kp)
+int enable_kprobe(struct kprobe *kp)
{
int ret = 0;
struct kprobe *p;
@@ -2043,8 +2042,8 @@
}
/* Module notifier call back, checking kprobes on the module */
-static int __kprobes kprobes_module_callback(struct notifier_block *nb,
- unsigned long val, void *data)
+static int kprobes_module_callback(struct notifier_block *nb,
+ unsigned long val, void *data)
{
struct module *mod = data;
struct hlist_head *head;
@@ -2145,7 +2144,7 @@
}
#ifdef CONFIG_DEBUG_FS
-static void __kprobes report_probe(struct seq_file *pi, struct kprobe *p,
+static void report_probe(struct seq_file *pi, struct kprobe *p,
const char *sym, int offset, char *modname, struct kprobe *pp)
{
char *kprobe_type;
@@ -2174,12 +2173,12 @@
(kprobe_ftrace(pp) ? "[FTRACE]" : ""));
}
-static void __kprobes *kprobe_seq_start(struct seq_file *f, loff_t *pos)
+static void *kprobe_seq_start(struct seq_file *f, loff_t *pos)
{
return (*pos < KPROBE_TABLE_SIZE) ? pos : NULL;
}
-static void __kprobes *kprobe_seq_next(struct seq_file *f, void *v, loff_t *pos)
+static void *kprobe_seq_next(struct seq_file *f, void *v, loff_t *pos)
{
(*pos)++;
if (*pos >= KPROBE_TABLE_SIZE)
@@ -2187,12 +2186,12 @@
return pos;
}
-static void __kprobes kprobe_seq_stop(struct seq_file *f, void *v)
+static void kprobe_seq_stop(struct seq_file *f, void *v)
{
/* Nothing to do */
}
-static int __kprobes show_kprobe_addr(struct seq_file *pi, void *v)
+static int show_kprobe_addr(struct seq_file *pi, void *v)
{
struct hlist_head *head;
struct kprobe *p, *kp;
@@ -2223,7 +2222,7 @@
.show = show_kprobe_addr
};
-static int __kprobes kprobes_open(struct inode *inode, struct file *filp)
+static int kprobes_open(struct inode *inode, struct file *filp)
{
return seq_open(filp, &kprobes_seq_ops);
}
@@ -2235,7 +2234,7 @@
.release = seq_release,
};
-static void __kprobes arm_all_kprobes(void)
+static void arm_all_kprobes(void)
{
struct hlist_head *head;
struct kprobe *p;
@@ -2263,7 +2262,7 @@
return;
}
-static void __kprobes disarm_all_kprobes(void)
+static void disarm_all_kprobes(void)
{
struct hlist_head *head;
struct kprobe *p;
@@ -2347,7 +2346,7 @@
.llseek = default_llseek,
};
-static int __kprobes debugfs_kprobe_init(void)
+static int __init debugfs_kprobe_init(void)
{
struct dentry *dir, *file;
unsigned int value = 1;