TechPanelGM/kernel_xiaomi_sm8250
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bpf: Explicitly memset some bpf info structures declared on the stack

Browse Source 
commit 5c6f25887963f15492b604dd25cb149c501bbabf upstream.

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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Greg Kroah-Hartman
2020-03-20 17:22:58 +01:00
parent aca6a9b098
commit 638d8c748e
2 changed files with 6 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
kernel/bpf/btf.c
View File

@@ -2387,7 +2387,7 @@ int btf_get_info_by_fd(const struct btf *btf,
union bpf_attr __user *uattr) union bpf_attr __user *uattr)
{ {
struct bpf_btf_info __user *uinfo; struct bpf_btf_info __user *uinfo;
struct bpf_btf_info info = {}; struct bpf_btf_info info;
u32 info_copy, btf_copy; u32 info_copy, btf_copy;
void __user *ubtf; void __user *ubtf;
u32 uinfo_len; u32 uinfo_len;
@@ -2396,6 +2396,7 @@ int btf_get_info_by_fd(const struct btf *btf,
uinfo_len = attr->info.info_len; uinfo_len = attr->info.info_len;
info_copy = min_t(u32, uinfo_len, sizeof(info)); info_copy = min_t(u32, uinfo_len, sizeof(info));
memset(&info, 0, sizeof(info));
if (copy_from_user(&info, uinfo, info_copy)) if (copy_from_user(&info, uinfo, info_copy))
return -EFAULT; return -EFAULT;

6
kernel/bpf/syscall.c
View File

@@ -1958,7 +1958,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
union bpf_attr __user *uattr) union bpf_attr __user *uattr)
{ {
struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); 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; u32 info_len = attr->info.info_len;
char __user *uinsns; char __user *uinsns;
u32 ulen; u32 ulen;
@@ -1969,6 +1969,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
return err; return err;
info_len = min_t(u32, sizeof(info), info_len); info_len = min_t(u32, sizeof(info), info_len);
memset(&info, 0, sizeof(info));
if (copy_from_user(&info, uinfo, info_len)) if (copy_from_user(&info, uinfo, info_len))
return -EFAULT; return -EFAULT;
@@ -2136,7 +2137,7 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map,
union bpf_attr __user *uattr) union bpf_attr __user *uattr)
{ {
struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info); 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; u32 info_len = attr->info.info_len;
int err; int err;
@@ -2145,6 +2146,7 @@ static int bpf_map_get_info_by_fd(struct bpf_map *map,
return err; return err;
info_len = min_t(u32, sizeof(info), info_len); info_len = min_t(u32, sizeof(info), info_len);
memset(&info, 0, sizeof(info));
info.type = map->map_type; info.type = map->map_type;
info.id = map->id; info.id = map->id;
info.key_size = map->key_size; info.key_size = map->key_size;