| Message ID | 20211019032934.1210517-1-xukuohai@huawei.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | BPF |
| Headers | show |
| Series | [bpf] bpf: Fix error usage of map_fd and fdget() in generic_map_update_batch() | expand |
On Mon, Oct 18, 2021 at 8:24 PM Xu Kuohai <xukuohai@huawei.com> wrote: > > 1. The ufd in generic_map_update_batch() should be read from batch.map_fd; > 2. A call to fdget() should be followed by a symmetric call to fdput(). > > Fixes: aa2e93b8e58e ("bpf: Add generic support for update and delete batch ops") > Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Ouch. Thanks for the fix. Applied. Brian, when your bugs are fixed please pay attention in the future and review the fix with Reviewed-by or Acked-by.
Oh I completely missed the first email. Sorry about that! Thanks for the patch Xu. On Thu, Oct 21, 2021 at 3:05 PM Alexei Starovoitov <alexei.starovoitov@gmail.com> wrote: > > On Mon, Oct 18, 2021 at 8:24 PM Xu Kuohai <xukuohai@huawei.com> wrote: > > > > 1. The ufd in generic_map_update_batch() should be read from batch.map_fd; > > 2. A call to fdget() should be followed by a symmetric call to fdput(). > > > > Fixes: aa2e93b8e58e ("bpf: Add generic support for update and delete batch ops") > > Signed-off-by: Xu Kuohai <xukuohai@huawei.com> > > Ouch. Thanks for the fix. Applied. > > Brian, > when your bugs are fixed please pay attention in the future and > review the fix with Reviewed-by or Acked-by.
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 4e50c0bfdb7d..9dab49d3f394 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1337,12 +1337,11 @@ int generic_map_update_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); u32 value_size, cp, max_count; - int ufd = attr->map_fd; + int ufd = attr->batch.map_fd; void *key, *value; struct fd f; int err = 0; - f = fdget(ufd); if (attr->batch.elem_flags & ~BPF_F_LOCK) return -EINVAL; @@ -1367,6 +1366,7 @@ int generic_map_update_batch(struct bpf_map *map, return -ENOMEM; } + f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */ for (cp = 0; cp < max_count; cp++) { err = -EFAULT; if (copy_from_user(key, keys + cp * map->key_size, @@ -1386,6 +1386,7 @@ int generic_map_update_batch(struct bpf_map *map, kvfree(value); kvfree(key); + fdput(f); return err; }
1. The ufd in generic_map_update_batch() should be read from batch.map_fd; 2. A call to fdget() should be followed by a symmetric call to fdput(). Fixes: aa2e93b8e58e ("bpf: Add generic support for update and delete batch ops") Signed-off-by: Xu Kuohai <xukuohai@huawei.com> --- kernel/bpf/syscall.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)