summaryrefslogtreecommitdiff
path: root/kernel/bpf
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/bpf')
-rw-r--r--kernel/bpf/helpers.c14
-rw-r--r--kernel/bpf/syscall.c35
2 files changed, 24 insertions, 25 deletions
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 13f870e47ab6..d3feaf6d68eb 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -3,6 +3,7 @@
*/
#include <linux/bpf.h>
#include <linux/rcupdate.h>
+#include <linux/rcupdate_trace.h>
#include <linux/random.h>
#include <linux/smp.h>
#include <linux/topology.h>
@@ -24,12 +25,13 @@
*
* Different map implementations will rely on rcu in map methods
* lookup/update/delete, therefore eBPF programs must run under rcu lock
- * if program is allowed to access maps, so check rcu_read_lock_held in
- * all three functions.
+ * if program is allowed to access maps, so check rcu_read_lock_held() or
+ * rcu_read_lock_trace_held() in all three functions.
*/
BPF_CALL_2(bpf_map_lookup_elem, struct bpf_map *, map, void *, key)
{
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
+ !rcu_read_lock_bh_held());
return (unsigned long) map->ops->map_lookup_elem(map, key);
}
@@ -45,7 +47,8 @@ const struct bpf_func_proto bpf_map_lookup_elem_proto = {
BPF_CALL_4(bpf_map_update_elem, struct bpf_map *, map, void *, key,
void *, value, u64, flags)
{
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
+ !rcu_read_lock_bh_held());
return map->ops->map_update_elem(map, key, value, flags);
}
@@ -62,7 +65,8 @@ const struct bpf_func_proto bpf_map_update_elem_proto = {
BPF_CALL_2(bpf_map_delete_elem, struct bpf_map *, map, void *, key)
{
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
+ !rcu_read_lock_bh_held());
return map->ops->map_delete_elem(map, key);
}
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 37aa1e319165..6f309248f13f 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -654,7 +654,7 @@ static const struct vm_operations_struct bpf_map_default_vmops = {
static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
{
struct bpf_map *map = filp->private_data;
- int err;
+ int err = 0;
if (!map->ops->map_mmap || map_value_has_spin_lock(map) ||
map_value_has_timer(map))
@@ -679,7 +679,12 @@ static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
err = -EACCES;
goto out;
}
+ bpf_map_write_active_inc(map);
}
+out:
+ mutex_unlock(&map->freeze_mutex);
+ if (err)
+ return err;
/* set default open/close callbacks */
vma->vm_ops = &bpf_map_default_vmops;
@@ -690,13 +695,11 @@ static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
vma->vm_flags &= ~VM_MAYWRITE;
err = map->ops->map_mmap(map, vma);
- if (err)
- goto out;
+ if (err) {
+ if (vma->vm_flags & VM_WRITE)
+ bpf_map_write_active_dec(map);
+ }
- if (vma->vm_flags & VM_MAYWRITE)
- bpf_map_write_active_inc(map);
-out:
- mutex_unlock(&map->freeze_mutex);
return err;
}
@@ -1435,8 +1438,6 @@ int generic_map_update_batch(struct bpf_map *map,
return err;
}
-#define MAP_LOOKUP_RETRIES 3
-
int generic_map_lookup_batch(struct bpf_map *map,
const union bpf_attr *attr,
union bpf_attr __user *uattr)
@@ -1446,8 +1447,8 @@ int generic_map_lookup_batch(struct bpf_map *map,
void __user *values = u64_to_user_ptr(attr->batch.values);
void __user *keys = u64_to_user_ptr(attr->batch.keys);
void *buf, *buf_prevkey, *prev_key, *key, *value;
- int err, retry = MAP_LOOKUP_RETRIES;
u32 value_size, cp, max_count;
+ int err;
if (attr->batch.elem_flags & ~BPF_F_LOCK)
return -EINVAL;
@@ -1493,14 +1494,8 @@ int generic_map_lookup_batch(struct bpf_map *map,
err = bpf_map_copy_value(map, key, value,
attr->batch.elem_flags);
- if (err == -ENOENT) {
- if (retry) {
- retry--;
- continue;
- }
- err = -EINTR;
- break;
- }
+ if (err == -ENOENT)
+ goto next_key;
if (err)
goto free_buf;
@@ -1515,12 +1510,12 @@ int generic_map_lookup_batch(struct bpf_map *map,
goto free_buf;
}
+ cp++;
+next_key:
if (!prev_key)
prev_key = buf_prevkey;
swap(prev_key, key);
- retry = MAP_LOOKUP_RETRIES;
- cp++;
cond_resched();
}