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-rw-r--r--kernel/trace/bpf_trace.c32
-rw-r--r--kernel/trace/ftrace.c8
-rw-r--r--kernel/trace/trace.c44
-rw-r--r--kernel/trace/trace_clock.c6
4 files changed, 50 insertions, 40 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index d2d7cf6cfe83..7a52bc172841 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -215,16 +215,11 @@ const struct bpf_func_proto bpf_probe_read_user_str_proto = {
static __always_inline int
bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr)
{
- int ret = security_locked_down(LOCKDOWN_BPF_READ);
+ int ret;
- if (unlikely(ret < 0))
- goto fail;
ret = copy_from_kernel_nofault(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
- goto fail;
- return ret;
-fail:
- memset(dst, 0, size);
+ memset(dst, 0, size);
return ret;
}
@@ -246,10 +241,7 @@ const struct bpf_func_proto bpf_probe_read_kernel_proto = {
static __always_inline int
bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
{
- int ret = security_locked_down(LOCKDOWN_BPF_READ);
-
- if (unlikely(ret < 0))
- goto fail;
+ int ret;
/*
* The strncpy_from_kernel_nofault() call will likely not fill the
@@ -262,11 +254,7 @@ bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
*/
ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
- goto fail;
-
- return ret;
-fail:
- memset(dst, 0, size);
+ memset(dst, 0, size);
return ret;
}
@@ -1011,16 +999,20 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
case BPF_FUNC_probe_read_user:
return &bpf_probe_read_user_proto;
case BPF_FUNC_probe_read_kernel:
- return &bpf_probe_read_kernel_proto;
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_kernel_proto;
case BPF_FUNC_probe_read_user_str:
return &bpf_probe_read_user_str_proto;
case BPF_FUNC_probe_read_kernel_str:
- return &bpf_probe_read_kernel_str_proto;
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_kernel_str_proto;
#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
case BPF_FUNC_probe_read:
- return &bpf_probe_read_compat_proto;
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_compat_proto;
case BPF_FUNC_probe_read_str:
- return &bpf_probe_read_compat_str_proto;
+ return security_locked_down(LOCKDOWN_BPF_READ) < 0 ?
+ NULL : &bpf_probe_read_compat_str_proto;
#endif
#ifdef CONFIG_CGROUPS
case BPF_FUNC_get_current_cgroup_id:
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 2e8a3fde7104..72ef4dccbcc4 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1967,12 +1967,18 @@ static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops,
static void print_ip_ins(const char *fmt, const unsigned char *p)
{
+ char ins[MCOUNT_INSN_SIZE];
int i;
+ if (copy_from_kernel_nofault(ins, p, MCOUNT_INSN_SIZE)) {
+ printk(KERN_CONT "%s[FAULT] %px\n", fmt, p);
+ return;
+ }
+
printk(KERN_CONT "%s", fmt);
for (i = 0; i < MCOUNT_INSN_SIZE; i++)
- printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]);
+ printk(KERN_CONT "%s%02x", i ? ":" : "", ins[i]);
}
enum ftrace_bug_type ftrace_bug_type;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 560e4c8d3825..d23a09d3eb37 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2198,9 +2198,6 @@ struct saved_cmdlines_buffer {
};
static struct saved_cmdlines_buffer *savedcmd;
-/* temporary disable recording */
-static atomic_t trace_record_taskinfo_disabled __read_mostly;
-
static inline char *get_saved_cmdlines(int idx)
{
return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN];
@@ -2486,8 +2483,6 @@ static bool tracing_record_taskinfo_skip(int flags)
{
if (unlikely(!(flags & (TRACE_RECORD_CMDLINE | TRACE_RECORD_TGID))))
return true;
- if (atomic_read(&trace_record_taskinfo_disabled) || !tracing_is_on())
- return true;
if (!__this_cpu_read(trace_taskinfo_save))
return true;
return false;
@@ -2736,7 +2731,7 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb,
(entry = this_cpu_read(trace_buffered_event))) {
/* Try to use the per cpu buffer first */
val = this_cpu_inc_return(trace_buffered_event_cnt);
- if ((len < (PAGE_SIZE - sizeof(*entry))) && val == 1) {
+ if ((len < (PAGE_SIZE - sizeof(*entry) - sizeof(entry->array[0]))) && val == 1) {
trace_event_setup(entry, type, trace_ctx);
entry->array[0] = len;
return entry;
@@ -3704,6 +3699,9 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
goto print;
while (*p) {
+ bool star = false;
+ int len = 0;
+
j = 0;
/* We only care about %s and variants */
@@ -3725,13 +3723,17 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
/* Need to test cases like %08.*s */
for (j = 1; p[i+j]; j++) {
if (isdigit(p[i+j]) ||
- p[i+j] == '*' ||
p[i+j] == '.')
continue;
+ if (p[i+j] == '*') {
+ star = true;
+ continue;
+ }
break;
}
if (p[i+j] == 's')
break;
+ star = false;
}
j = 0;
}
@@ -3744,6 +3746,9 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
iter->fmt[i] = '\0';
trace_seq_vprintf(&iter->seq, iter->fmt, ap);
+ if (star)
+ len = va_arg(ap, int);
+
/* The ap now points to the string data of the %s */
str = va_arg(ap, const char *);
@@ -3762,8 +3767,18 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
int ret;
/* Try to safely read the string */
- ret = strncpy_from_kernel_nofault(iter->fmt, str,
- iter->fmt_size);
+ if (star) {
+ if (len + 1 > iter->fmt_size)
+ len = iter->fmt_size - 1;
+ if (len < 0)
+ len = 0;
+ ret = copy_from_kernel_nofault(iter->fmt, str, len);
+ iter->fmt[len] = 0;
+ star = false;
+ } else {
+ ret = strncpy_from_kernel_nofault(iter->fmt, str,
+ iter->fmt_size);
+ }
if (ret < 0)
trace_seq_printf(&iter->seq, "(0x%px)", str);
else
@@ -3775,7 +3790,10 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
strncpy(iter->fmt, p + i, j + 1);
iter->fmt[j+1] = '\0';
}
- trace_seq_printf(&iter->seq, iter->fmt, str);
+ if (star)
+ trace_seq_printf(&iter->seq, iter->fmt, len, str);
+ else
+ trace_seq_printf(&iter->seq, iter->fmt, str);
p += i + j + 1;
}
@@ -3975,9 +3993,6 @@ static void *s_start(struct seq_file *m, loff_t *pos)
return ERR_PTR(-EBUSY);
#endif
- if (!iter->snapshot)
- atomic_inc(&trace_record_taskinfo_disabled);
-
if (*pos != iter->pos) {
iter->ent = NULL;
iter->cpu = 0;
@@ -4020,9 +4035,6 @@ static void s_stop(struct seq_file *m, void *p)
return;
#endif
- if (!iter->snapshot)
- atomic_dec(&trace_record_taskinfo_disabled);
-
trace_access_unlock(iter->cpu_file);
trace_event_read_unlock();
}
diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c
index c1637f90c8a3..4702efb00ff2 100644
--- a/kernel/trace/trace_clock.c
+++ b/kernel/trace/trace_clock.c
@@ -115,9 +115,9 @@ u64 notrace trace_clock_global(void)
prev_time = READ_ONCE(trace_clock_struct.prev_time);
now = sched_clock_cpu(this_cpu);
- /* Make sure that now is always greater than prev_time */
+ /* Make sure that now is always greater than or equal to prev_time */
if ((s64)(now - prev_time) < 0)
- now = prev_time + 1;
+ now = prev_time;
/*
* If in an NMI context then dont risk lockups and simply return
@@ -131,7 +131,7 @@ u64 notrace trace_clock_global(void)
/* Reread prev_time in case it was already updated */
prev_time = READ_ONCE(trace_clock_struct.prev_time);
if ((s64)(now - prev_time) < 0)
- now = prev_time + 1;
+ now = prev_time;
trace_clock_struct.prev_time = now;