Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-12-18 00:53:40 +00:00
Code Issues Packages Projects Releases Wiki Activity

fix "netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1'"

Browse Source 
Descriptor table is a shared object; it's not a place where you can
stick temporary references to files, especially when we don't need
an opened file at all.

Cc: stable@vger.kernel.org # v4.14
Fixes: 98589a0998 ("netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1'")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2017-12-02 20:20:38 -05:00
parent 9ee332d99e
commit 040ee69226
4 changed files with 52 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
include/linux/bpf.h
View File

@ -419,6 +419,8 @@ static inline int bpf_map_attr_numa_node(const union bpf_attr *attr)
attr->numa_node : NUMA_NO_NODE;
}
struct bpf_prog *bpf_prog_get_type_path(const char *name, enum bpf_prog_type type);
#else /* !CONFIG_BPF_SYSCALL */
static inline struct bpf_prog *bpf_prog_get(u32 ufd)
{
@ -506,6 +508,12 @@ static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
{
return 0;
}
static inline struct bpf_prog *bpf_prog_get_type_path(const char *name,
enum bpf_prog_type type)
{
return ERR_PTR(-EOPNOTSUPP);
}
#endif /* CONFIG_BPF_SYSCALL */
static inline struct bpf_prog *bpf_prog_get_type(u32 ufd,
@ -514,6 +522,8 @@ static inline struct bpf_prog *bpf_prog_get_type(u32 ufd,
return bpf_prog_get_type_dev(ufd, type, false);
}
bool bpf_prog_get_ok(struct bpf_prog *, enum bpf_prog_type *, bool);
int bpf_prog_offload_compile(struct bpf_prog *prog);
void bpf_prog_offload_destroy(struct bpf_prog *prog);

40
kernel/bpf/inode.c
View File

@ -368,7 +368,45 @@ out:
putname(pname);
return ret;
}
EXPORT_SYMBOL_GPL(bpf_obj_get_user);
static struct bpf_prog *__get_prog_inode(struct inode *inode, enum bpf_prog_type type)
{
struct bpf_prog *prog;
int ret = inode_permission(inode, MAY_READ | MAY_WRITE);
if (ret)
return ERR_PTR(ret);
if (inode->i_op == &bpf_map_iops)
return ERR_PTR(-EINVAL);
if (inode->i_op != &bpf_prog_iops)
return ERR_PTR(-EACCES);
prog = inode->i_private;
ret = security_bpf_prog(prog);
if (ret < 0)
return ERR_PTR(ret);
if (!bpf_prog_get_ok(prog, &type, false))
return ERR_PTR(-EINVAL);
return bpf_prog_inc(prog);
}
struct bpf_prog *bpf_prog_get_type_path(const char *name, enum bpf_prog_type type)
{
struct bpf_prog *prog;
struct path path;
int ret = kern_path(name, LOOKUP_FOLLOW, &path);
if (ret)
return ERR_PTR(ret);
prog = __get_prog_inode(d_backing_inode(path.dentry), type);
if (!IS_ERR(prog))
touch_atime(&path);
path_put(&path);
return prog;
}
EXPORT_SYMBOL(bpf_prog_get_type_path);
static void bpf_evict_inode(struct inode *inode)
{

2
kernel/bpf/syscall.c
View File

@ -1057,7 +1057,7 @@ struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
}
EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
static bool bpf_prog_get_ok(struct bpf_prog *prog,
bool bpf_prog_get_ok(struct bpf_prog *prog,
enum bpf_prog_type *attach_type, bool attach_drv)
{
/* not an attachment, just a refcount inc, always allow */

14
net/netfilter/xt_bpf.c
View File

@ -52,18 +52,8 @@ static int __bpf_mt_check_fd(int fd, struct bpf_prog **ret)
static int __bpf_mt_check_path(const char *path, struct bpf_prog **ret)
{
mm_segment_t oldfs = get_fs();
int retval, fd;
set_fs(KERNEL_DS);
fd = bpf_obj_get_user(path, 0);
set_fs(oldfs);
if (fd < 0)
return fd;
retval = __bpf_mt_check_fd(fd, ret);
sys_close(fd);
return retval;
*ret = bpf_prog_get_type_path(path, BPF_PROG_TYPE_SOCKET_FILTER);
return PTR_ERR_OR_ZERO(*ret);
}
static int bpf_mt_check(const struct xt_mtchk_param *par)