diff options
| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-03-20 17:22:58 +0100 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2020-03-20 21:05:22 +0100 |
| commit | 5c6f25887963f15492b604dd25cb149c501bbabf (patch) | |
| tree | 0ca35ad39945fc8e516682d2dd353e2802bfddc6 | |
| parent | 8096f229421f7b22433775e928d506f0342e5907 (diff) | |
bpf: Explicitly memset some bpf info structures declared on the stack
Trying to initialize a structure with "= {};" will not always clean out
all padding locations in a structure. So be explicit and call memset to
initialize everything for a number of bpf information structures that
are then copied from userspace, sometimes from smaller memory locations
than the size of the structure.
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200320162258.GA794295@kroah.com
| -rw-r--r-- | kernel/bpf/btf.c | 3 | ||||
| -rw-r--r-- | kernel/bpf/syscall.c | 6 |
2 files changed, 6 insertions, 3 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 32ab9225026e..7787bdcb5d68 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -4564,7 +4564,7 @@ int btf_get_info_by_fd(const struct btf *btf, union bpf_attr __user *uattr) { struct bpf_btf_info __user *uinfo; - struct bpf_btf_info info = {}; + struct bpf_btf_info info; u32 info_copy, btf_copy; void __user *ubtf; u32 uinfo_len; @@ -4573,6 +4573,7 @@ int btf_get_info_by_fd(const struct btf *btf, uinfo_len = attr->info.info_len; info_copy = min_t(u32, uinfo_len, sizeof(info)); + memset(&info, 0, sizeof(info)); if (copy_from_user(&info, uinfo, info_copy)) return -EFAULT; diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 3ac1629cf00e..966b7b34cde0 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -2795,7 +2795,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, union bpf_attr __user *uattr) { struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); - struct bpf_prog_info info = {}; + struct bpf_prog_info info; u32 info_len = attr->info.info_len; struct bpf_prog_stats stats; char __user *uinsns; @@ -2807,6 +2807,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, return err; info_len = min_t(u32, sizeof(info), info_len); + memset(&info, 0, sizeof(info)); if (copy_from_user(&info, uinfo, info_len)) return -EFAULT; @@ -3070,7 +3071,7 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map, union bpf_attr __user *uattr) { struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); - struct bpf_map_info info = {}; + struct bpf_map_info info; u32 info_len = attr->info.info_len; int err; @@ -3079,6 +3080,7 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map, return err; info_len = min_t(u32, sizeof(info), info_len); + memset(&info, 0, sizeof(info)); info.type = map->map_type; info.id = map->id; info.key_size = map->key_size; |