From 196e8ca74886c433dcfc64a809707074b936aaf5 Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <daniel@iogearbox.net>
Date: Wed, 20 Nov 2019 23:04:44 +0100
Subject: [PATCH] bpf: Switch bpf_map_{area_alloc,area_mmapable_alloc}() to u64
size
Given we recently extended the original bpf_map_area_alloc() helper in
commit fc9702273e2e ("bpf: Add mmap() support for BPF_MAP_TYPE_ARRAY"),
we need to apply the same logic as in ff1c08e1f74b ("bpf: Change size
to u64 for bpf_map_{area_alloc, charge_init}()"). To avoid conflicts,
extend it for bpf-next.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
---
include/linux/bpf.h | 6 +++---
kernel/bpf/syscall.c | 11 +++++++----
2 files changed, 10 insertions(+), 7 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index e913dd5946ae7..e89e861222336 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -794,12 +794,12 @@ void bpf_map_put_with_uref(struct bpf_map *map);
void bpf_map_put(struct bpf_map *map);
int bpf_map_charge_memlock(struct bpf_map *map, u32 pages);
void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages);
-int bpf_map_charge_init(struct bpf_map_memory *mem, size_t size);
+int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size);
void bpf_map_charge_finish(struct bpf_map_memory *mem);
void bpf_map_charge_move(struct bpf_map_memory *dst,
struct bpf_map_memory *src);
-void *bpf_map_area_alloc(size_t size, int numa_node);
-void *bpf_map_area_mmapable_alloc(size_t size, int numa_node);
+void *bpf_map_area_alloc(u64 size, int numa_node);
+void *bpf_map_area_mmapable_alloc(u64 size, int numa_node);
void bpf_map_area_free(void *base);
void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 17f4254495f24..b51ecb9644d0e 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -128,7 +128,7 @@ static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
return map;
}
-static void *__bpf_map_area_alloc(size_t size, int numa_node, bool mmapable)
+static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
{
/* We really just want to fail instead of triggering OOM killer
* under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
@@ -143,6 +143,9 @@ static void *__bpf_map_area_alloc(size_t size, int numa_node, bool mmapable)
const gfp_t flags = __GFP_NOWARN | __GFP_ZERO;
void *area;
+ if (size >= SIZE_MAX)
+ return NULL;
+
/* kmalloc()'ed memory can't be mmap()'ed */
if (!mmapable && size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags,
@@ -160,12 +163,12 @@ static void *__bpf_map_area_alloc(size_t size, int numa_node, bool mmapable)
flags, __builtin_return_address(0));
}
-void *bpf_map_area_alloc(size_t size, int numa_node)
+void *bpf_map_area_alloc(u64 size, int numa_node)
{
return __bpf_map_area_alloc(size, numa_node, false);
}
-void *bpf_map_area_mmapable_alloc(size_t size, int numa_node)
+void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
{
return __bpf_map_area_alloc(size, numa_node, true);
}
@@ -214,7 +217,7 @@ static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
atomic_long_sub(pages, &user->locked_vm);
}
-int bpf_map_charge_init(struct bpf_map_memory *mem, size_t size)
+int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size)
{
u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT;
struct user_struct *user;