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Diffstat (limited to 'kernel/trace/bpf_trace.c')
-rw-r--r--kernel/trace/bpf_trace.c94
1 files changed, 62 insertions, 32 deletions
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index b83bdaa31c7b..a010edc37ee0 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -323,17 +323,15 @@ static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
/*
* Only limited trace_printk() conversion specifiers allowed:
- * %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %s
+ * %d %i %u %x %ld %li %lu %lx %lld %lli %llu %llx %p %pks %pus %s
*/
BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
u64, arg2, u64, arg3)
{
+ int i, mod[3] = {}, fmt_cnt = 0;
+ char buf[64], fmt_ptype;
+ void *unsafe_ptr = NULL;
bool str_seen = false;
- int mod[3] = {};
- int fmt_cnt = 0;
- u64 unsafe_addr;
- char buf[64];
- int i;
/*
* bpf_check()->check_func_arg()->check_stack_boundary()
@@ -359,40 +357,71 @@ BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
if (fmt[i] == 'l') {
mod[fmt_cnt]++;
i++;
- } else if (fmt[i] == 'p' || fmt[i] == 's') {
+ } else if (fmt[i] == 'p') {
mod[fmt_cnt]++;
+ if ((fmt[i + 1] == 'k' ||
+ fmt[i + 1] == 'u') &&
+ fmt[i + 2] == 's') {
+ fmt_ptype = fmt[i + 1];
+ i += 2;
+ goto fmt_str;
+ }
+
/* disallow any further format extensions */
if (fmt[i + 1] != 0 &&
!isspace(fmt[i + 1]) &&
!ispunct(fmt[i + 1]))
return -EINVAL;
- fmt_cnt++;
- if (fmt[i] == 's') {
- if (str_seen)
- /* allow only one '%s' per fmt string */
- return -EINVAL;
- str_seen = true;
-
- switch (fmt_cnt) {
- case 1:
- unsafe_addr = arg1;
- arg1 = (long) buf;
- break;
- case 2:
- unsafe_addr = arg2;
- arg2 = (long) buf;
- break;
- case 3:
- unsafe_addr = arg3;
- arg3 = (long) buf;
- break;
- }
- buf[0] = 0;
- strncpy_from_unsafe(buf,
- (void *) (long) unsafe_addr,
+
+ goto fmt_next;
+ } else if (fmt[i] == 's') {
+ mod[fmt_cnt]++;
+ fmt_ptype = fmt[i];
+fmt_str:
+ if (str_seen)
+ /* allow only one '%s' per fmt string */
+ return -EINVAL;
+ str_seen = true;
+
+ if (fmt[i + 1] != 0 &&
+ !isspace(fmt[i + 1]) &&
+ !ispunct(fmt[i + 1]))
+ return -EINVAL;
+
+ switch (fmt_cnt) {
+ case 0:
+ unsafe_ptr = (void *)(long)arg1;
+ arg1 = (long)buf;
+ break;
+ case 1:
+ unsafe_ptr = (void *)(long)arg2;
+ arg2 = (long)buf;
+ break;
+ case 2:
+ unsafe_ptr = (void *)(long)arg3;
+ arg3 = (long)buf;
+ break;
+ }
+
+ buf[0] = 0;
+ switch (fmt_ptype) {
+ case 's':
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+ strncpy_from_unsafe(buf, unsafe_ptr,
sizeof(buf));
+ break;
+#endif
+ case 'k':
+ strncpy_from_unsafe_strict(buf, unsafe_ptr,
+ sizeof(buf));
+ break;
+ case 'u':
+ strncpy_from_unsafe_user(buf,
+ (__force void __user *)unsafe_ptr,
+ sizeof(buf));
+ break;
}
- continue;
+ goto fmt_next;
}
if (fmt[i] == 'l') {
@@ -403,6 +432,7 @@ BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
if (fmt[i] != 'i' && fmt[i] != 'd' &&
fmt[i] != 'u' && fmt[i] != 'x')
return -EINVAL;
+fmt_next:
fmt_cnt++;
}