bpf: hash map: decrement counter on error

[ Upstream commit ed2b82c03dc187018307c7c6bf9299705f3db383 ]

Decrement the number of elements in the map in case the allocation
of a new node fails.

Fixes: 6c9059817432 ("bpf: pre-allocate hash map elements")
Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mauricio Vasquez B 2018-06-29 14:48:20 +02:00 committed by Greg Kroah-Hartman
parent fa97c91627
commit 56f059c87b

View File

@ -730,13 +730,15 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
* old element will be freed immediately.
* Otherwise return an error
*/
atomic_dec(&htab->count);
return ERR_PTR(-E2BIG);
l_new = ERR_PTR(-E2BIG);
goto dec_count;
}
l_new = kmalloc_node(htab->elem_size, GFP_ATOMIC | __GFP_NOWARN,
htab->map.numa_node);
if (!l_new)
return ERR_PTR(-ENOMEM);
if (!l_new) {
l_new = ERR_PTR(-ENOMEM);
goto dec_count;
}
}
memcpy(l_new->key, key, key_size);
@ -749,7 +751,8 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
GFP_ATOMIC | __GFP_NOWARN);
if (!pptr) {
kfree(l_new);
return ERR_PTR(-ENOMEM);
l_new = ERR_PTR(-ENOMEM);
goto dec_count;
}
}
@ -763,6 +766,9 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
l_new->hash = hash;
return l_new;
dec_count:
atomic_dec(&htab->count);
return l_new;
}
static int check_flags(struct bpf_htab *htab, struct htab_elem *l_old,