bpf: use kvmemdup_bpfptr helper

Use kvmemdup_bpfptr helper instead of open-coding to
simplify the code.

Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/1663058433-14089-1-git-send-email-wangyufen@huawei.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 69be1c6..dab156f 100644 (file)
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1417,19 +1417,14 @@ static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
        }
 
        value_size = bpf_map_value_size(map);
-
-       err = -ENOMEM;
-       value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
-       if (!value)
+       value = kvmemdup_bpfptr(uvalue, value_size);
+       if (IS_ERR(value)) {
+               err = PTR_ERR(value);
                goto free_key;
-
-       err = -EFAULT;
-       if (copy_from_bpfptr(value, uvalue, value_size) != 0)
-               goto free_value;
+       }
 
        err = bpf_map_update_value(map, f, key, value, attr->flags);
 
-free_value:
        kvfree(value);
 free_key:
        kvfree(key);