From: Michal Hocko <mhocko@xxxxxxxx>
01b3f52157ff ("bpf: fix allocation warnings in bpf maps and integer
overflow") has added checks for the maximum allocateable size. It
(ab)used KMALLOC_SHIFT_MAX for that purpose. While this is not incorrect
it is not very clean because we already have KMALLOC_MAX_SIZE for this
very reason so let's change both checks to use KMALLOC_MAX_SIZE instead.
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>
---
kernel/bpf/arraymap.c | 2 +-
kernel/bpf/hashtab.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index a2ac051c342f..229a5d5df977 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -56,7 +56,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
attr->value_size == 0 || attr->map_flags)
return ERR_PTR(-EINVAL);
- if (attr->value_size >= 1 << (KMALLOC_SHIFT_MAX - 1))
+ if (attr->value_size > KMALLOC_MAX_SIZE)
/* if value_size is bigger, the user space won't be able to
* access the elements.
*/
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index ad1bc67aff1b..c5ec7dc71c84 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -181,7 +181,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
*/
goto free_htab;
- if (htab->map.value_size >= (1 << (KMALLOC_SHIFT_MAX - 1)) -
+ if (htab->map.value_size >= KMALLOC_MAX_SIZE -
MAX_BPF_STACK - sizeof(struct htab_elem))
/* if value_size is bigger, the user space won't be able to
* access the elements via bpf syscall. This check also makes
--
2.10.2
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>