Update Linux to v5.4.148
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz
Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 53534aa..a7812c1 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -326,7 +326,8 @@
struct kprobe *p;
head = &kprobe_table[hash_ptr(addr, KPROBE_HASH_BITS)];
- hlist_for_each_entry_rcu(p, head, hlist) {
+ hlist_for_each_entry_rcu(p, head, hlist,
+ lockdep_is_held(&kprobe_mutex)) {
if (p->addr == addr)
return p;
}
@@ -510,6 +511,8 @@
arch_unoptimize_kprobes(&unoptimizing_list, &freeing_list);
/* Loop free_list for disarming */
list_for_each_entry_safe(op, tmp, &freeing_list, list) {
+ /* Switching from detour code to origin */
+ op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED;
/* Disarm probes if marked disabled */
if (kprobe_disabled(&op->kp))
arch_disarm_kprobe(&op->kp);
@@ -584,11 +587,12 @@
mutex_unlock(&module_mutex);
mutex_unlock(&text_mutex);
cpus_read_unlock();
- mutex_unlock(&kprobe_mutex);
/* Step 5: Kick optimizer again if needed */
if (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list))
kick_kprobe_optimizer();
+
+ mutex_unlock(&kprobe_mutex);
}
/* Wait for completing optimization and unoptimization */
@@ -610,6 +614,18 @@
mutex_unlock(&kprobe_mutex);
}
+static bool optprobe_queued_unopt(struct optimized_kprobe *op)
+{
+ struct optimized_kprobe *_op;
+
+ list_for_each_entry(_op, &unoptimizing_list, list) {
+ if (op == _op)
+ return true;
+ }
+
+ return false;
+}
+
/* Optimize kprobe if p is ready to be optimized */
static void optimize_kprobe(struct kprobe *p)
{
@@ -631,17 +647,21 @@
return;
/* Check if it is already optimized. */
- if (op->kp.flags & KPROBE_FLAG_OPTIMIZED)
+ if (op->kp.flags & KPROBE_FLAG_OPTIMIZED) {
+ if (optprobe_queued_unopt(op)) {
+ /* This is under unoptimizing. Just dequeue the probe */
+ list_del_init(&op->list);
+ }
return;
+ }
op->kp.flags |= KPROBE_FLAG_OPTIMIZED;
- if (!list_empty(&op->list))
- /* This is under unoptimizing. Just dequeue the probe */
- list_del_init(&op->list);
- else {
- list_add(&op->list, &optimizing_list);
- kick_kprobe_optimizer();
- }
+ /* On unoptimizing/optimizing_list, op must have OPTIMIZED flag */
+ if (WARN_ON_ONCE(!list_empty(&op->list)))
+ return;
+
+ list_add(&op->list, &optimizing_list);
+ kick_kprobe_optimizer();
}
/* Short cut to direct unoptimizing */
@@ -649,6 +669,7 @@
{
lockdep_assert_cpus_held();
arch_unoptimize_kprobe(op);
+ op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED;
if (kprobe_disabled(&op->kp))
arch_disarm_kprobe(&op->kp);
}
@@ -662,31 +683,33 @@
return; /* This is not an optprobe nor optimized */
op = container_of(p, struct optimized_kprobe, kp);
- if (!kprobe_optimized(p)) {
- /* Unoptimized or unoptimizing case */
- if (force && !list_empty(&op->list)) {
- /*
- * Only if this is unoptimizing kprobe and forced,
- * forcibly unoptimize it. (No need to unoptimize
- * unoptimized kprobe again :)
- */
+ if (!kprobe_optimized(p))
+ return;
+
+ if (!list_empty(&op->list)) {
+ if (optprobe_queued_unopt(op)) {
+ /* Queued in unoptimizing queue */
+ if (force) {
+ /*
+ * Forcibly unoptimize the kprobe here, and queue it
+ * in the freeing list for release afterwards.
+ */
+ force_unoptimize_kprobe(op);
+ list_move(&op->list, &freeing_list);
+ }
+ } else {
+ /* Dequeue from the optimizing queue */
list_del_init(&op->list);
- force_unoptimize_kprobe(op);
+ op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED;
}
return;
}
- op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED;
- if (!list_empty(&op->list)) {
- /* Dequeue from the optimization queue */
- list_del_init(&op->list);
- return;
- }
/* Optimized kprobe case */
- if (force)
+ if (force) {
/* Forcibly update the code: this is a special case */
force_unoptimize_kprobe(op);
- else {
+ } else {
list_add(&op->list, &unoptimizing_list);
kick_kprobe_optimizer();
}
@@ -1053,9 +1076,20 @@
ipmodify ? &kprobe_ipmodify_enabled : &kprobe_ftrace_enabled);
}
#else /* !CONFIG_KPROBES_ON_FTRACE */
-#define prepare_kprobe(p) arch_prepare_kprobe(p)
-#define arm_kprobe_ftrace(p) (-ENODEV)
-#define disarm_kprobe_ftrace(p) (-ENODEV)
+static inline int prepare_kprobe(struct kprobe *p)
+{
+ return arch_prepare_kprobe(p);
+}
+
+static inline int arm_kprobe_ftrace(struct kprobe *p)
+{
+ return -ENODEV;
+}
+
+static inline int disarm_kprobe_ftrace(struct kprobe *p)
+{
+ return -ENODEV;
+}
#endif
/* Arm a kprobe with text_mutex */
@@ -1215,6 +1249,26 @@
}
NOKPROBE_SYMBOL(kretprobe_table_unlock);
+struct kprobe kprobe_busy = {
+ .addr = (void *) get_kprobe,
+};
+
+void kprobe_busy_begin(void)
+{
+ struct kprobe_ctlblk *kcb;
+
+ preempt_disable();
+ __this_cpu_write(current_kprobe, &kprobe_busy);
+ kcb = get_kprobe_ctlblk();
+ kcb->kprobe_status = KPROBE_HIT_ACTIVE;
+}
+
+void kprobe_busy_end(void)
+{
+ __this_cpu_write(current_kprobe, NULL);
+ preempt_enable();
+}
+
/*
* This function is called from finish_task_switch when task tk becomes dead,
* so that we can recycle any function-return probe instances associated
@@ -1232,6 +1286,8 @@
/* Early boot. kretprobe_table_locks not yet initialized. */
return;
+ kprobe_busy_begin();
+
INIT_HLIST_HEAD(&empty_rp);
hash = hash_ptr(tk, KPROBE_HASH_BITS);
head = &kretprobe_inst_table[hash];
@@ -1245,6 +1301,8 @@
hlist_del(&ri->hlist);
kfree(ri);
}
+
+ kprobe_busy_end();
}
NOKPROBE_SYMBOL(kprobe_flush_task);
@@ -1890,28 +1948,48 @@
return !offset;
}
-bool kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset)
+/**
+ * kprobe_on_func_entry() -- check whether given address is function entry
+ * @addr: Target address
+ * @sym: Target symbol name
+ * @offset: The offset from the symbol or the address
+ *
+ * This checks whether the given @addr+@offset or @sym+@offset is on the
+ * function entry address or not.
+ * This returns 0 if it is the function entry, or -EINVAL if it is not.
+ * And also it returns -ENOENT if it fails the symbol or address lookup.
+ * Caller must pass @addr or @sym (either one must be NULL), or this
+ * returns -EINVAL.
+ */
+int kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long offset)
{
kprobe_opcode_t *kp_addr = _kprobe_addr(addr, sym, offset);
if (IS_ERR(kp_addr))
- return false;
+ return PTR_ERR(kp_addr);
- if (!kallsyms_lookup_size_offset((unsigned long)kp_addr, NULL, &offset) ||
- !arch_kprobe_on_func_entry(offset))
- return false;
+ if (!kallsyms_lookup_size_offset((unsigned long)kp_addr, NULL, &offset))
+ return -ENOENT;
- return true;
+ if (!arch_kprobe_on_func_entry(offset))
+ return -EINVAL;
+
+ return 0;
}
int register_kretprobe(struct kretprobe *rp)
{
- int ret = 0;
+ int ret;
struct kretprobe_instance *inst;
int i;
void *addr;
- if (!kprobe_on_func_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset))
+ ret = kprobe_on_func_entry(rp->kp.addr, rp->kp.symbol_name, rp->kp.offset);
+ if (ret)
+ return ret;
+
+ /* If only rp->kp.addr is specified, check reregistering kprobes */
+ if (rp->kp.addr && check_kprobe_rereg(&rp->kp))
return -EINVAL;
if (kretprobe_blacklist_size) {
@@ -2041,6 +2119,9 @@
{
struct kprobe *kp;
+ if (WARN_ON_ONCE(kprobe_gone(p)))
+ return;
+
p->flags |= KPROBE_FLAG_GONE;
if (kprobe_aggrprobe(p)) {
/*
@@ -2057,6 +2138,14 @@
* the original probed function (which will be freed soon) any more.
*/
arch_remove_kprobe(p);
+
+ /*
+ * The module is going away. We should disarm the kprobe which
+ * is using ftrace, because ftrace framework is still available at
+ * MODULE_STATE_GOING notification.
+ */
+ if (kprobe_ftrace(p) && !kprobe_disabled(p) && !kprobes_all_disarmed)
+ disarm_kprobe_ftrace(p);
}
/* Disable one kprobe */
@@ -2216,7 +2305,10 @@
mutex_lock(&kprobe_mutex);
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
- hlist_for_each_entry_rcu(p, head, hlist)
+ hlist_for_each_entry_rcu(p, head, hlist) {
+ if (kprobe_gone(p))
+ continue;
+
if (within_module_init((unsigned long)p->addr, mod) ||
(checkcore &&
within_module_core((unsigned long)p->addr, mod))) {
@@ -2233,6 +2325,7 @@
*/
kill_kprobe(p);
}
+ }
}
mutex_unlock(&kprobe_mutex);
return NOTIFY_DONE;
@@ -2247,6 +2340,28 @@
extern unsigned long __start_kprobe_blacklist[];
extern unsigned long __stop_kprobe_blacklist[];
+void kprobe_free_init_mem(void)
+{
+ void *start = (void *)(&__init_begin);
+ void *end = (void *)(&__init_end);
+ struct hlist_head *head;
+ struct kprobe *p;
+ int i;
+
+ mutex_lock(&kprobe_mutex);
+
+ /* Kill all kprobes on initmem */
+ for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
+ head = &kprobe_table[i];
+ hlist_for_each_entry(p, head, hlist) {
+ if (start <= (void *)p->addr && (void *)p->addr < end)
+ kill_kprobe(p);
+ }
+ }
+
+ mutex_unlock(&kprobe_mutex);
+}
+
static int __init init_kprobes(void)
{
int i, err = 0;
@@ -2315,7 +2430,7 @@
else
kprobe_type = "k";
- if (!kallsyms_show_value())
+ if (!kallsyms_show_value(pi->file->f_cred))
addr = NULL;
if (sym)
@@ -2416,7 +2531,7 @@
* If /proc/kallsyms is not showing kernel address, we won't
* show them here either.
*/
- if (!kallsyms_show_value())
+ if (!kallsyms_show_value(m->file->f_cred))
seq_printf(m, "0x%px-0x%px\t%ps\n", NULL, NULL,
(void *)ent->start_addr);
else