From: Brian Vazquez <brianvv@google.com>
To: Brian Vazquez <brianvv.kernel@gmail.com>,
Brian Vazquez <brianvv@google.com>,
Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
"David S . Miller" <davem@davemloft.net>
Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
bpf@vger.kernel.org, Dan Carpenter <dan.carpenter@oracle.com>
Subject: [PATCH bpf-next] bpf: Fix memory leaks in generic update/delete batch ops
Date: Fri, 17 Jan 2020 14:56:08 -0800 [thread overview]
Message-ID: <20200117225608.220838-1-brianvv@google.com> (raw)
generic update/delete batch ops functions were using __bpf_copy_key
without properly freeing the memory. Handle the memory allocation and
copy_from_user separately.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: aa2e93b8e58e ("bpf: Add generic support for update and delete
batch ops")
Signed-off-by: Brian Vazquez <brianvv@google.com>
---
kernel/bpf/syscall.c | 30 +++++++++++++++++++-----------
1 file changed, 19 insertions(+), 11 deletions(-)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index c26a71460f02f..9a840c57f6df7 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1239,12 +1239,15 @@ int generic_map_delete_batch(struct bpf_map *map,
if (!max_count)
return 0;
+ key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
+ if (!key)
+ return -ENOMEM;
+
for (cp = 0; cp < max_count; cp++) {
- key = __bpf_copy_key(keys + cp * map->key_size, map->key_size);
- if (IS_ERR(key)) {
- err = PTR_ERR(key);
+ err = -EFAULT;
+ if (copy_from_user(key, keys + cp * map->key_size,
+ map->key_size))
break;
- }
if (bpf_map_is_dev_bound(map)) {
err = bpf_map_offload_delete_elem(map, key);
@@ -1264,6 +1267,8 @@ int generic_map_delete_batch(struct bpf_map *map,
}
if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
err = -EFAULT;
+
+ kfree(key);
return err;
}
@@ -1294,18 +1299,21 @@ int generic_map_update_batch(struct bpf_map *map,
if (!max_count)
return 0;
+ key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
+ if (!key)
+ return -ENOMEM;
+
value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
- if (!value)
+ if (!value) {
+ kfree(key);
return -ENOMEM;
+ }
for (cp = 0; cp < max_count; cp++) {
- key = __bpf_copy_key(keys + cp * map->key_size, map->key_size);
- if (IS_ERR(key)) {
- err = PTR_ERR(key);
- break;
- }
err = -EFAULT;
- if (copy_from_user(value, values + cp * value_size, value_size))
+ if (copy_from_user(key, keys + cp * map->key_size,
+ map->key_size) ||
+ copy_from_user(value, values + cp * value_size, value_size))
break;
err = bpf_map_update_value(map, f, key, value,
--
2.25.0.341.g760bfbb309-goog
next reply other threads:[~2020-01-17 22:56 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-17 22:56 Brian Vazquez [this message]
2020-01-18 4:14 ` [PATCH bpf-next] bpf: Fix memory leaks in generic update/delete batch ops Yonghong Song
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