Re: [RFC bpf-next 3/5] bpf: pin, translate, and unpin __kptr_user from syscalls.

[Kui-Feng Lee <sinquersw@gmail.com>]

On 8/12/24 09:45, Alexei Starovoitov wrote:
> On Wed, Aug 7, 2024 at 4:58 PM Kui-Feng Lee <thinker.li@gmail.com> wrote:
>>
>> User kptrs are pinned, by pin_user_pages_fast(), and translated to an
>> address in the kernel when the value is updated by user programs. (Call
>> bpf_map_update_elem() from user programs.) And, the pinned pages are
>> unpinned if the value of user kptrs are overritten or if the values of maps
>> are deleted/destroyed.
>>
>> The pages are mapped through vmap() in order to get a continuous space in
>> the kernel if the memory pointed by a user kptr resides in two or more
>> pages. For the case of single page, page_address() is called to get the
>> address of a page in the kernel.
>>
>> User kptr is only supported by task storage maps.
>>
>> One user kptr can pin at most KPTR_USER_MAX_PAGES(16) physical pages. This
>> is a random picked number for safety. We actually can remove this
>> restriction totally.
>>
>> User kptrs could only be set by user programs through syscalls.  Any
>> attempts of updating the value of a map with __kptr_user in it should
>> ignore the values of user kptrs from BPF programs. The values of user kptrs
>> will keep as they were if the new values are from BPF programs, not from
>> user programs.
>>
>> Cc: linux-mm@kvack.org
>> Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
>> ---
>>   include/linux/bpf.h               |  35 +++++-
>>   include/linux/bpf_local_storage.h |   2 +-
>>   kernel/bpf/bpf_local_storage.c    |  18 +--
>>   kernel/bpf/helpers.c              |  12 +-
>>   kernel/bpf/local_storage.c        |   2 +-
>>   kernel/bpf/syscall.c              | 177 +++++++++++++++++++++++++++++-
>>   net/core/bpf_sk_storage.c         |   2 +-
>>   7 files changed, 227 insertions(+), 21 deletions(-)
>>
>> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
>> index 87d5f98249e2..f4ad0bc183cb 100644
>> --- a/include/linux/bpf.h
>> +++ b/include/linux/bpf.h
>> @@ -30,6 +30,7 @@
>>   #include <linux/static_call.h>
>>   #include <linux/memcontrol.h>
>>   #include <linux/cfi.h>
>> +#include <linux/mm.h>
>>
>>   struct bpf_verifier_env;
>>   struct bpf_verifier_log;
>> @@ -477,10 +478,12 @@ static inline void bpf_long_memcpy(void *dst, const void *src, u32 size)
>>                  data_race(*ldst++ = *lsrc++);
>>   }
>>
>> +void bpf_obj_unpin_uaddr(const struct btf_field *field, void *addr);
>> +
>>   /* copy everything but bpf_spin_lock, bpf_timer, and kptrs. There could be one of each. */
>>   static inline void bpf_obj_memcpy(struct btf_record *rec,
>>                                    void *dst, void *src, u32 size,
>> -                                 bool long_memcpy)
>> +                                 bool long_memcpy, bool from_user)
>>   {
>>          u32 curr_off = 0;
>>          int i;
>> @@ -496,21 +499,40 @@ static inline void bpf_obj_memcpy(struct btf_record *rec,
>>          for (i = 0; i < rec->cnt; i++) {
>>                  u32 next_off = rec->fields[i].offset;
>>                  u32 sz = next_off - curr_off;
>> +               void *addr;
>>
>>                  memcpy(dst + curr_off, src + curr_off, sz);
>> +               if (from_user && rec->fields[i].type == BPF_KPTR_USER) {
> 
> 
> Do not add this to bpf_obj_memcpy() which is a critical path
> for various map operations.
> This has to be standalone for task storage only.
> 
>> +                       /* Unpin old address.
>> +                        *
>> +                        * Alignments are guaranteed by btf_find_field_one().
>> +                        */
>> +                       addr = *(void **)(dst + next_off);
>> +                       if (virt_addr_valid(addr))
>> +                               bpf_obj_unpin_uaddr(&rec->fields[i], addr);
>> +                       else if (addr)
>> +                               WARN_ON_ONCE(1);
>> +
>> +                       *(void **)(dst + next_off) = *(void **)(src + next_off);
>> +               }
>>                  curr_off += rec->fields[i].size + sz;
>>          }
>>          memcpy(dst + curr_off, src + curr_off, size - curr_off);
>>   }
>>
>> +static inline void copy_map_value_user(struct bpf_map *map, void *dst, void *src, bool from_user)
> 
> No need for these helpers either.
> 
>> +{
>> +       bpf_obj_memcpy(map->record, dst, src, map->value_size, false, from_user);
>> +}
>> +
>>   static inline void copy_map_value(struct bpf_map *map, void *dst, void *src)
>>   {
>> -       bpf_obj_memcpy(map->record, dst, src, map->value_size, false);
>> +       bpf_obj_memcpy(map->record, dst, src, map->value_size, false, false);
>>   }
>>
>>   static inline void copy_map_value_long(struct bpf_map *map, void *dst, void *src)
>>   {
>> -       bpf_obj_memcpy(map->record, dst, src, map->value_size, true);
>> +       bpf_obj_memcpy(map->record, dst, src, map->value_size, true, false);
>>   }
>>
>>   static inline void bpf_obj_memzero(struct btf_record *rec, void *dst, u32 size)
>> @@ -538,6 +560,8 @@ static inline void zero_map_value(struct bpf_map *map, void *dst)
>>          bpf_obj_memzero(map->record, dst, map->value_size);
>>   }
>>
>> +void copy_map_value_locked_user(struct bpf_map *map, void *dst, void *src,
>> +                               bool lock_src, bool from_user);
>>   void copy_map_value_locked(struct bpf_map *map, void *dst, void *src,
>>                             bool lock_src);
>>   void bpf_timer_cancel_and_free(void *timer);
>> @@ -775,6 +799,11 @@ enum bpf_arg_type {
>>   };
>>   static_assert(__BPF_ARG_TYPE_MAX <= BPF_BASE_TYPE_LIMIT);
>>
>> +#define BPF_MAP_UPDATE_FLAG_BITS 3
>> +enum bpf_map_update_flag {
>> +       BPF_FROM_USER = BIT(0 + BPF_MAP_UPDATE_FLAG_BITS)
>> +};
>> +
>>   /* type of values returned from helper functions */
>>   enum bpf_return_type {
>>          RET_INTEGER,                    /* function returns integer */
>> diff --git a/include/linux/bpf_local_storage.h b/include/linux/bpf_local_storage.h
>> index dcddb0aef7d8..d337df68fa23 100644
>> --- a/include/linux/bpf_local_storage.h
>> +++ b/include/linux/bpf_local_storage.h
>> @@ -181,7 +181,7 @@ void bpf_selem_link_map(struct bpf_local_storage_map *smap,
>>
>>   struct bpf_local_storage_elem *
>>   bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner, void *value,
>> -               bool charge_mem, gfp_t gfp_flags);
>> +               bool charge_mem, gfp_t gfp_flags, bool from_user);
>>
>>   void bpf_selem_free(struct bpf_local_storage_elem *selem,
>>                      struct bpf_local_storage_map *smap,
>> diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c
>> index c938dea5ddbf..c4cf09e27a19 100644
>> --- a/kernel/bpf/bpf_local_storage.c
>> +++ b/kernel/bpf/bpf_local_storage.c
>> @@ -73,7 +73,7 @@ static bool selem_linked_to_map(const struct bpf_local_storage_elem *selem)
>>
>>   struct bpf_local_storage_elem *
>>   bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner,
>> -               void *value, bool charge_mem, gfp_t gfp_flags)
>> +               void *value, bool charge_mem, gfp_t gfp_flags, bool from_user)
>>   {
>>          struct bpf_local_storage_elem *selem;
>>
>> @@ -100,7 +100,7 @@ bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner,
>>
>>          if (selem) {
>>                  if (value)
>> -                       copy_map_value(&smap->map, SDATA(selem)->data, value);
>> +                       copy_map_value_user(&smap->map, SDATA(selem)->data, value, from_user);
>>                  /* No need to call check_and_init_map_value as memory is zero init */
>>                  return selem;
>>          }
>> @@ -530,9 +530,11 @@ bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap,
>>          struct bpf_local_storage_elem *alloc_selem, *selem = NULL;
>>          struct bpf_local_storage *local_storage;
>>          unsigned long flags;
>> +       bool from_user = map_flags & BPF_FROM_USER;
>>          int err;
>>
>>          /* BPF_EXIST and BPF_NOEXIST cannot be both set */
>> +       map_flags &= ~BPF_FROM_USER;
>>          if (unlikely((map_flags & ~BPF_F_LOCK) > BPF_EXIST) ||
>>              /* BPF_F_LOCK can only be used in a value with spin_lock */
>>              unlikely((map_flags & BPF_F_LOCK) &&
>> @@ -550,7 +552,7 @@ bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap,
>>                  if (err)
>>                          return ERR_PTR(err);
>>
>> -               selem = bpf_selem_alloc(smap, owner, value, true, gfp_flags);
>> +               selem = bpf_selem_alloc(smap, owner, value, true, gfp_flags, from_user);
>>                  if (!selem)
>>                          return ERR_PTR(-ENOMEM);
>>
>> @@ -575,8 +577,8 @@ bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap,
>>                  if (err)
>>                          return ERR_PTR(err);
>>                  if (old_sdata && selem_linked_to_storage_lockless(SELEM(old_sdata))) {
>> -                       copy_map_value_locked(&smap->map, old_sdata->data,
>> -                                             value, false);
>> +                       copy_map_value_locked_user(&smap->map, old_sdata->data,
>> +                                                  value, false, from_user);
>>                          return old_sdata;
>>                  }
>>          }
>> @@ -584,7 +586,7 @@ bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap,
>>          /* A lookup has just been done before and concluded a new selem is
>>           * needed. The chance of an unnecessary alloc is unlikely.
>>           */
>> -       alloc_selem = selem = bpf_selem_alloc(smap, owner, value, true, gfp_flags);
>> +       alloc_selem = selem = bpf_selem_alloc(smap, owner, value, true, gfp_flags, from_user);
>>          if (!alloc_selem)
>>                  return ERR_PTR(-ENOMEM);
>>
>> @@ -607,8 +609,8 @@ bpf_local_storage_update(void *owner, struct bpf_local_storage_map *smap,
>>                  goto unlock;
>>
>>          if (old_sdata && (map_flags & BPF_F_LOCK)) {
>> -               copy_map_value_locked(&smap->map, old_sdata->data, value,
>> -                                     false);
>> +               copy_map_value_locked_user(&smap->map, old_sdata->data, value,
>> +                                          false, from_user);
>>                  selem = SELEM(old_sdata);
>>                  goto unlock;
>>          }
>> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
>> index d02ae323996b..4aef86209fdd 100644
>> --- a/kernel/bpf/helpers.c
>> +++ b/kernel/bpf/helpers.c
>> @@ -372,8 +372,8 @@ const struct bpf_func_proto bpf_spin_unlock_proto = {
>>          .arg1_btf_id    = BPF_PTR_POISON,
>>   };
>>
>> -void copy_map_value_locked(struct bpf_map *map, void *dst, void *src,
>> -                          bool lock_src)
>> +void copy_map_value_locked_user(struct bpf_map *map, void *dst, void *src,
>> +                               bool lock_src, bool from_user)
>>   {
>>          struct bpf_spin_lock *lock;
>>
>> @@ -383,11 +383,17 @@ void copy_map_value_locked(struct bpf_map *map, void *dst, void *src,
>>                  lock = dst + map->record->spin_lock_off;
>>          preempt_disable();
>>          __bpf_spin_lock_irqsave(lock);
>> -       copy_map_value(map, dst, src);
>> +       copy_map_value_user(map, dst, src, from_user);
>>          __bpf_spin_unlock_irqrestore(lock);
>>          preempt_enable();
>>   }
>>
>> +void copy_map_value_locked(struct bpf_map *map, void *dst, void *src,
>> +                          bool lock_src)
>> +{
>> +       copy_map_value_locked_user(map, dst, src, lock_src, false);
>> +}
>> +
>>   BPF_CALL_0(bpf_jiffies64)
>>   {
>>          return get_jiffies_64();
>> diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
>> index 3969eb0382af..62a12fa8ce9e 100644
>> --- a/kernel/bpf/local_storage.c
>> +++ b/kernel/bpf/local_storage.c
>> @@ -147,7 +147,7 @@ static long cgroup_storage_update_elem(struct bpf_map *map, void *key,
>>          struct bpf_cgroup_storage *storage;
>>          struct bpf_storage_buffer *new;
>>
>> -       if (unlikely(flags & ~(BPF_F_LOCK | BPF_EXIST)))
>> +       if (unlikely(flags & ~BPF_F_LOCK))
>>                  return -EINVAL;
>>
>>          if (unlikely((flags & BPF_F_LOCK) &&
>> diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
>> index 90a25307480e..eaa2a9d13265 100644
>> --- a/kernel/bpf/syscall.c
>> +++ b/kernel/bpf/syscall.c
>> @@ -155,8 +155,134 @@ static void maybe_wait_bpf_programs(struct bpf_map *map)
>>                  synchronize_rcu();
>>   }
>>
>> -static int bpf_map_update_value(struct bpf_map *map, struct file *map_file,
>> -                               void *key, void *value, __u64 flags)
>> +static void *trans_addr_pages(struct page **pages, int npages)
>> +{
>> +       if (npages == 1)
>> +               return page_address(pages[0]);
>> +       /* For multiple pages, we need to use vmap() to get a contiguous
>> +        * virtual address range.
>> +        */
>> +       return vmap(pages, npages, VM_MAP, PAGE_KERNEL);
>> +}
> 
> Don't quite see a need for trans_addr_pages() helper when it's used
> once.
> 
>> +
>> +#define KPTR_USER_MAX_PAGES 16
>> +
>> +static int bpf_obj_trans_pin_uaddr(struct btf_field *field, void **addr)
>> +{
>> +       const struct btf_type *t;
>> +       struct page *pages[KPTR_USER_MAX_PAGES];
>> +       void *ptr, *kern_addr;
>> +       u32 type_id, tsz;
>> +       int r, npages;
>> +
>> +       ptr = *addr;
>> +       type_id = field->kptr.btf_id;
>> +       t = btf_type_id_size(field->kptr.btf, &type_id, &tsz);
>> +       if (!t)
>> +               return -EINVAL;
>> +       if (tsz == 0) {
>> +               *addr = NULL;
>> +               return 0;
>> +       }
>> +
>> +       npages = (((intptr_t)ptr + tsz + ~PAGE_MASK) -
>> +                 ((intptr_t)ptr & PAGE_MASK)) >> PAGE_SHIFT;
>> +       if (npages > KPTR_USER_MAX_PAGES)
>> +               return -E2BIG;
>> +       r = pin_user_pages_fast((intptr_t)ptr & PAGE_MASK, npages, 0, pages);
> 
> No need to apply the mask on ptr. See pin_user_pages_fast() internals.
> 
> It probably should be FOLL_WRITE | FOLL_LONGTERM instead of 0.

Agree!

> 
>> +       if (r != npages)
>> +               return -EINVAL;
>> +       kern_addr = trans_addr_pages(pages, npages);
>> +       if (!kern_addr)
>> +               return -ENOMEM;
>> +       *addr = kern_addr + ((intptr_t)ptr & ~PAGE_MASK);
>> +       return 0;
>> +}
>> +
>> +void bpf_obj_unpin_uaddr(const struct btf_field *field, void *addr)
>> +{
>> +       struct page *pages[KPTR_USER_MAX_PAGES];
>> +       int npages, i;
>> +       u32 size, type_id;
>> +       void *ptr;
>> +
>> +       type_id = field->kptr.btf_id;
>> +       btf_type_id_size(field->kptr.btf, &type_id, &size);
>> +       if (size == 0)
>> +               return;
>> +
>> +       ptr = (void *)((intptr_t)addr & PAGE_MASK);
>> +       npages = (((intptr_t)addr + size + ~PAGE_MASK) - (intptr_t)ptr) >> PAGE_SHIFT;
>> +       for (i = 0; i < npages; i++) {
>> +               pages[i] = virt_to_page(ptr);
>> +               ptr += PAGE_SIZE;
>> +       }
>> +       if (npages > 1)
>> +               /* Paired with vmap() in trans_addr_pages() */
>> +               vunmap((void *)((intptr_t)addr & PAGE_MASK));
>> +       unpin_user_pages(pages, npages);
>> +}
>> +
>> +static int bpf_obj_trans_pin_uaddrs(struct btf_record *rec, void *src, u32 size)
>> +{
>> +       u32 next_off;
>> +       int i, err;
>> +
>> +       if (IS_ERR_OR_NULL(rec))
>> +               return 0;
>> +
>> +       if (!btf_record_has_field(rec, BPF_KPTR_USER))
>> +               return 0;
> 
> imo kptr_user doesn't quite fit as a name.
> 'kptr' means 'kernel pointer'. Here it's user addr.
> Maybe just "uptr" ?

That makes sense.

> 
>> +
>> +       for (i = 0; i < rec->cnt; i++) {
>> +               if (rec->fields[i].type != BPF_KPTR_USER)
>> +                       continue;
>> +
>> +               next_off = rec->fields[i].offset;
>> +               if (next_off + sizeof(void *) > size)
>> +                       return -EINVAL;
>> +               err = bpf_obj_trans_pin_uaddr(&rec->fields[i], src + next_off);
>> +               if (!err)
>> +                       continue;
>> +
>> +               /* Rollback */
>> +               for (i--; i >= 0; i--) {
>> +                       if (rec->fields[i].type != BPF_KPTR_USER)
>> +                               continue;
>> +                       next_off = rec->fields[i].offset;
>> +                       bpf_obj_unpin_uaddr(&rec->fields[i], *(void **)(src + next_off));
>> +                       *(void **)(src + next_off) = NULL;
>> +               }
>> +
>> +               return err;
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +static void bpf_obj_unpin_uaddrs(struct btf_record *rec, void *src)
>> +{
>> +       u32 next_off;
>> +       int i;
>> +
>> +       if (IS_ERR_OR_NULL(rec))
>> +               return;
>> +
>> +       if (!btf_record_has_field(rec, BPF_KPTR_USER))
>> +               return;
>> +
>> +       for (i = 0; i < rec->cnt; i++) {
>> +               if (rec->fields[i].type != BPF_KPTR_USER)
>> +                       continue;
>> +
>> +               next_off = rec->fields[i].offset;
>> +               bpf_obj_unpin_uaddr(&rec->fields[i], *(void **)(src + next_off));
>> +               *(void **)(src + next_off) = NULL;
> 
> This part is pretty much the same as the undo part in
> bpf_obj_trans_pin_uaddrs() and the common helper is warranted.

Sure!

> 
>> +       }
>> +}
>> +
>> +static int bpf_map_update_value_inner(struct bpf_map *map, struct file *map_file,
>> +                                     void *key, void *value, __u64 flags)
>>   {
>>          int err;
>>
>> @@ -208,6 +334,29 @@ static int bpf_map_update_value(struct bpf_map *map, struct file *map_file,
>>          return err;
>>   }
>>
>> +static int bpf_map_update_value(struct bpf_map *map, struct file *map_file,
>> +                               void *key, void *value, __u64 flags)
>> +{
>> +       int err;
>> +
>> +       if (flags & BPF_FROM_USER) {
> 
> there shouldn't be a need for this extra flag.
> map->record has the info whether uptr is present or not.

The BPF_FROM_USER flag is used to support updating map values from BPF
programs as well. Although BPF programs can udpate map values, I
don't want the values of uptrs to be changed by the BPF programs.

Should we just forbid the BPF programs to udpate the map values having
uptrs in them?


> 
>> +               /* Pin user memory can lead to context switch, so we need
>> +                * to do it before potential RCU lock.
>> +                */
>> +               err = bpf_obj_trans_pin_uaddrs(map->record, value,
>> +                                              bpf_map_value_size(map));
>> +               if (err)
>> +                       return err;
>> +       }
>> +
>> +       err = bpf_map_update_value_inner(map, map_file, key, value, flags);
>> +
>> +       if (err && (flags & BPF_FROM_USER))
>> +               bpf_obj_unpin_uaddrs(map->record, value);
>> +
>> +       return err;
>> +}
>> +
>>   static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
>>                                __u64 flags)
>>   {
>> @@ -714,6 +863,11 @@ void bpf_obj_free_fields(const struct btf_record *rec, void *obj)
>>                                  field->kptr.dtor(xchgd_field);
>>                          }
>>                          break;
>> +               case BPF_KPTR_USER:
>> +                       if (virt_addr_valid(*(void **)field_ptr))
>> +                               bpf_obj_unpin_uaddr(field, *(void **)field_ptr);
>> +                       *(void **)field_ptr = NULL;
>> +                       break;
>>                  case BPF_LIST_HEAD:
>>                          if (WARN_ON_ONCE(rec->spin_lock_off < 0))
>>                                  continue;
>> @@ -1155,6 +1309,12 @@ static int map_check_btf(struct bpf_map *map, struct bpf_token *token,
>>                                          goto free_map_tab;
>>                                  }
>>                                  break;
>> +                       case BPF_KPTR_USER:
>> +                               if (map->map_type != BPF_MAP_TYPE_TASK_STORAGE) {
>> +                                       ret = -EOPNOTSUPP;
>> +                                       goto free_map_tab;
>> +                               }
>> +                               break;
>>                          case BPF_LIST_HEAD:
>>                          case BPF_RB_ROOT:
>>                                  if (map->map_type != BPF_MAP_TYPE_HASH &&
>> @@ -1618,11 +1778,15 @@ static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
>>          struct bpf_map *map;
>>          void *key, *value;
>>          u32 value_size;
>> +       u64 extra_flags = 0;
>>          struct fd f;
>>          int err;
>>
>>          if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
>>                  return -EINVAL;
>> +       /* Prevent userspace from setting any internal flags */
>> +       if (attr->flags & ~(BIT(BPF_MAP_UPDATE_FLAG_BITS) - 1))
>> +               return -EINVAL;
>>
>>          f = fdget(ufd);
>>          map = __bpf_map_get(f);
>> @@ -1653,7 +1817,9 @@ static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
>>                  goto free_key;
>>          }
>>
>> -       err = bpf_map_update_value(map, f.file, key, value, attr->flags);
>> +       if (map->map_type == BPF_MAP_TYPE_TASK_STORAGE)
>> +               extra_flags |= BPF_FROM_USER;
>> +       err = bpf_map_update_value(map, f.file, key, value, attr->flags | extra_flags);
>>          if (!err)
>>                  maybe_wait_bpf_programs(map);
>>
>> @@ -1852,6 +2018,7 @@ int generic_map_update_batch(struct bpf_map *map, struct file *map_file,
>>          void __user *keys = u64_to_user_ptr(attr->batch.keys);
>>          u32 value_size, cp, max_count;
>>          void *key, *value;
>> +       u64 extra_flags = 0;
>>          int err = 0;
>>
>>          if (attr->batch.elem_flags & ~BPF_F_LOCK)
>> @@ -1881,6 +2048,8 @@ int generic_map_update_batch(struct bpf_map *map, struct file *map_file,
>>                  return -ENOMEM;
>>          }
>>
>> +       if (map->map_type == BPF_MAP_TYPE_TASK_STORAGE)
>> +               extra_flags |= BPF_FROM_USER;
>>          for (cp = 0; cp < max_count; cp++) {
>>                  err = -EFAULT;
>>                  if (copy_from_user(key, keys + cp * map->key_size,
>> @@ -1889,7 +2058,7 @@ int generic_map_update_batch(struct bpf_map *map, struct file *map_file,
>>                          break;
>>
>>                  err = bpf_map_update_value(map, map_file, key, value,
>> -                                          attr->batch.elem_flags);
>> +                                          attr->batch.elem_flags | extra_flags);
>>
>>                  if (err)
>>                          break;
>> diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c
>> index bc01b3aa6b0f..db5281384e6a 100644
>> --- a/net/core/bpf_sk_storage.c
>> +++ b/net/core/bpf_sk_storage.c
>> @@ -137,7 +137,7 @@ bpf_sk_storage_clone_elem(struct sock *newsk,
>>   {
>>          struct bpf_local_storage_elem *copy_selem;
>>
>> -       copy_selem = bpf_selem_alloc(smap, newsk, NULL, true, GFP_ATOMIC);
>> +       copy_selem = bpf_selem_alloc(smap, newsk, NULL, true, GFP_ATOMIC, false);
>>          if (!copy_selem)
>>                  return NULL;
>>
>> --
>> 2.34.1
>>