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Diffstat (limited to 'kernel/trace/trace_events_user.c')
-rw-r--r--kernel/trace/trace_events_user.c73
1 files changed, 59 insertions, 14 deletions
diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c
index 33cb6af31f39..b87f41187c6a 100644
--- a/kernel/trace/trace_events_user.c
+++ b/kernel/trace/trace_events_user.c
@@ -127,8 +127,13 @@ struct user_event_enabler {
/* Bit 7 is for freeing status of enablement */
#define ENABLE_VAL_FREEING_BIT 7
-/* Only duplicate the bit value */
-#define ENABLE_VAL_DUP_MASK ENABLE_VAL_BIT_MASK
+/* Bit 8 is for marking 32-bit on 64-bit */
+#define ENABLE_VAL_32_ON_64_BIT 8
+
+#define ENABLE_VAL_COMPAT_MASK (1 << ENABLE_VAL_32_ON_64_BIT)
+
+/* Only duplicate the bit and compat values */
+#define ENABLE_VAL_DUP_MASK (ENABLE_VAL_BIT_MASK | ENABLE_VAL_COMPAT_MASK)
#define ENABLE_BITOPS(e) (&(e)->values)
@@ -174,6 +179,30 @@ struct user_event_validator {
int flags;
};
+static inline void align_addr_bit(unsigned long *addr, int *bit,
+ unsigned long *flags)
+{
+ if (IS_ALIGNED(*addr, sizeof(long))) {
+#ifdef __BIG_ENDIAN
+ /* 32 bit on BE 64 bit requires a 32 bit offset when aligned. */
+ if (test_bit(ENABLE_VAL_32_ON_64_BIT, flags))
+ *bit += 32;
+#endif
+ return;
+ }
+
+ *addr = ALIGN_DOWN(*addr, sizeof(long));
+
+ /*
+ * We only support 32 and 64 bit values. The only time we need
+ * to align is a 32 bit value on a 64 bit kernel, which on LE
+ * is always 32 bits, and on BE requires no change when unaligned.
+ */
+#ifdef __LITTLE_ENDIAN
+ *bit += 32;
+#endif
+}
+
typedef void (*user_event_func_t) (struct user_event *user, struct iov_iter *i,
void *tpdata, bool *faulted);
@@ -482,6 +511,7 @@ static int user_event_enabler_write(struct user_event_mm *mm,
unsigned long *ptr;
struct page *page;
void *kaddr;
+ int bit = ENABLE_BIT(enabler);
int ret;
lockdep_assert_held(&event_mutex);
@@ -497,6 +527,8 @@ static int user_event_enabler_write(struct user_event_mm *mm,
test_bit(ENABLE_VAL_FREEING_BIT, ENABLE_BITOPS(enabler))))
return -EBUSY;
+ align_addr_bit(&uaddr, &bit, ENABLE_BITOPS(enabler));
+
ret = pin_user_pages_remote(mm->mm, uaddr, 1, FOLL_WRITE | FOLL_NOFAULT,
&page, NULL);
@@ -515,9 +547,9 @@ static int user_event_enabler_write(struct user_event_mm *mm,
/* Update bit atomically, user tracers must be atomic as well */
if (enabler->event && enabler->event->status)
- set_bit(ENABLE_BIT(enabler), ptr);
+ set_bit(bit, ptr);
else
- clear_bit(ENABLE_BIT(enabler), ptr);
+ clear_bit(bit, ptr);
kunmap_local(kaddr);
unpin_user_pages_dirty_lock(&page, 1, true);
@@ -849,6 +881,12 @@ static struct user_event_enabler
enabler->event = user;
enabler->addr = uaddr;
enabler->values = reg->enable_bit;
+
+#if BITS_PER_LONG >= 64
+ if (reg->enable_size == 4)
+ set_bit(ENABLE_VAL_32_ON_64_BIT, ENABLE_BITOPS(enabler));
+#endif
+
retry:
/* Prevents state changes from racing with new enablers */
mutex_lock(&event_mutex);
@@ -1328,14 +1366,14 @@ static int user_field_set_string(struct ftrace_event_field *field,
static int user_event_set_print_fmt(struct user_event *user, char *buf, int len)
{
- struct ftrace_event_field *field, *next;
+ struct ftrace_event_field *field;
struct list_head *head = &user->fields;
int pos = 0, depth = 0;
const char *str_func;
pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
- list_for_each_entry_safe_reverse(field, next, head, link) {
+ list_for_each_entry_reverse(field, head, link) {
if (depth != 0)
pos += snprintf(buf + pos, LEN_OR_ZERO, " ");
@@ -1347,7 +1385,7 @@ static int user_event_set_print_fmt(struct user_event *user, char *buf, int len)
pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
- list_for_each_entry_safe_reverse(field, next, head, link) {
+ list_for_each_entry_reverse(field, head, link) {
if (user_field_is_dyn_string(field->type, &str_func))
pos += snprintf(buf + pos, LEN_OR_ZERO,
", %s(%s)", str_func, field->name);
@@ -1732,7 +1770,7 @@ static int user_event_create(const char *raw_command)
static int user_event_show(struct seq_file *m, struct dyn_event *ev)
{
struct user_event *user = container_of(ev, struct user_event, devent);
- struct ftrace_event_field *field, *next;
+ struct ftrace_event_field *field;
struct list_head *head;
int depth = 0;
@@ -1740,7 +1778,7 @@ static int user_event_show(struct seq_file *m, struct dyn_event *ev)
head = trace_get_fields(&user->call);
- list_for_each_entry_safe_reverse(field, next, head, link) {
+ list_for_each_entry_reverse(field, head, link) {
if (depth == 0)
seq_puts(m, " ");
else
@@ -1816,13 +1854,14 @@ out:
static bool user_fields_match(struct user_event *user, int argc,
const char **argv)
{
- struct ftrace_event_field *field, *next;
+ struct ftrace_event_field *field;
struct list_head *head = &user->fields;
int i = 0;
- list_for_each_entry_safe_reverse(field, next, head, link)
+ list_for_each_entry_reverse(field, head, link) {
if (!user_field_match(field, argc, argv, &i))
return false;
+ }
if (i != argc)
return false;
@@ -2376,7 +2415,8 @@ static long user_unreg_get(struct user_unreg __user *ureg,
}
static int user_event_mm_clear_bit(struct user_event_mm *user_mm,
- unsigned long uaddr, unsigned char bit)
+ unsigned long uaddr, unsigned char bit,
+ unsigned long flags)
{
struct user_event_enabler enabler;
int result;
@@ -2384,7 +2424,7 @@ static int user_event_mm_clear_bit(struct user_event_mm *user_mm,
memset(&enabler, 0, sizeof(enabler));
enabler.addr = uaddr;
- enabler.values = bit;
+ enabler.values = bit | flags;
retry:
/* Prevents state changes from racing with new enablers */
mutex_lock(&event_mutex);
@@ -2414,6 +2454,7 @@ static long user_events_ioctl_unreg(unsigned long uarg)
struct user_event_mm *mm = current->user_event_mm;
struct user_event_enabler *enabler, *next;
struct user_unreg reg;
+ unsigned long flags;
long ret;
ret = user_unreg_get(ureg, &reg);
@@ -2424,6 +2465,7 @@ static long user_events_ioctl_unreg(unsigned long uarg)
if (!mm)
return -ENOENT;
+ flags = 0;
ret = -ENOENT;
/*
@@ -2440,6 +2482,9 @@ static long user_events_ioctl_unreg(unsigned long uarg)
ENABLE_BIT(enabler) == reg.disable_bit) {
set_bit(ENABLE_VAL_FREEING_BIT, ENABLE_BITOPS(enabler));
+ /* We must keep compat flags for the clear */
+ flags |= enabler->values & ENABLE_VAL_COMPAT_MASK;
+
if (!test_bit(ENABLE_VAL_FAULTING_BIT, ENABLE_BITOPS(enabler)))
user_event_enabler_destroy(enabler, true);
@@ -2453,7 +2498,7 @@ static long user_events_ioctl_unreg(unsigned long uarg)
/* Ensure bit is now cleared for user, regardless of event status */
if (!ret)
ret = user_event_mm_clear_bit(mm, reg.disable_addr,
- reg.disable_bit);
+ reg.disable_bit, flags);
return ret;
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-07-15 06:27:35 +0300