Signed-off-by: Hannes Frederic Sowa <han...@stressinduktion.org>
---
 include/linux/filter.h | 6 ++++--
 kernel/bpf/core.c      | 4 +++-
 kernel/bpf/syscall.c   | 7 ++++---
 kernel/bpf/verifier.c  | 4 ++--
 net/core/filter.c      | 6 +++---
 5 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/include/linux/filter.h b/include/linux/filter.h
index 63624c619e371b..635311f57bf24f 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -413,7 +413,8 @@ struct bpf_prog {
                                locked:1,       /* Program image locked? */
                                gpl_compatible:1, /* Is filter GPL compatible? 
*/
                                cb_access:1,    /* Is control block accessed? */
-                               dst_needed:1;   /* Do we need dst entry? */
+                               dst_needed:1,   /* Do we need dst entry? */
+                               priv_cap_sys_admin:1; /* Where we loaded as 
sys_admin? */
        kmemcheck_bitfield_end(meta);
        enum bpf_prog_type      type;           /* Type of BPF program */
        u32                     len;            /* Number of filter blocks */
@@ -615,7 +616,8 @@ static inline int sk_filter(struct sock *sk, struct sk_buff 
*skb)
 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err);
 void bpf_prog_free(struct bpf_prog *fp);
 
-struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
+struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags,
+                               bool cap_sys_admin);
 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
                                  gfp_t gfp_extra_flags);
 void __bpf_prog_free(struct bpf_prog *fp);
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 2139118258cdf8..048e2d79718a16 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -74,7 +74,8 @@ void *bpf_internal_load_pointer_neg_helper(const struct 
sk_buff *skb, int k, uns
        return NULL;
 }
 
-struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
+struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags,
+                               bool cap_sys_admin)
 {
        gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO |
                          gfp_extra_flags;
@@ -94,6 +95,7 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t 
gfp_extra_flags)
                return NULL;
        }
 
+       fp->priv_cap_sys_admin = cap_sys_admin;
        fp->pages = size / PAGE_SIZE;
        fp->aux = aux;
        fp->aux->prog = fp;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index d61d1bd3e6fee6..ed698c17578a49 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -786,7 +786,7 @@ EXPORT_SYMBOL_GPL(bpf_prog_get_type);
 /* last field in 'union bpf_attr' used by this command */
 #define        BPF_PROG_LOAD_LAST_FIELD kern_version
 
-static int bpf_prog_load(union bpf_attr *attr)
+static int bpf_prog_load(union bpf_attr *attr, bool cap_sys_admin)
 {
        enum bpf_prog_type type = attr->prog_type;
        struct bpf_prog *prog;
@@ -817,7 +817,8 @@ static int bpf_prog_load(union bpf_attr *attr)
                return -EPERM;
 
        /* plain bpf_prog allocation */
-       prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
+       prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER,
+                             cap_sys_admin);
        if (!prog)
                return -ENOMEM;
 
@@ -1053,7 +1054,7 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, 
uattr, unsigned int, siz
                err = map_get_next_key(&attr);
                break;
        case BPF_PROG_LOAD:
-               err = bpf_prog_load(&attr);
+               err = bpf_prog_load(&attr, capable(CAP_SYS_ADMIN));
                break;
        case BPF_OBJ_PIN:
                err = bpf_obj_pin(&attr);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 6f8b6ed690be93..24c9dac374770f 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3488,7 +3488,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr 
*attr)
        if (ret < 0)
                goto skip_full_check;
 
-       env->allow_ptr_leaks = capable(CAP_SYS_ADMIN);
+       env->allow_ptr_leaks = env->prog->priv_cap_sys_admin;
 
        ret = do_check(env);
 
@@ -3589,7 +3589,7 @@ int bpf_analyzer(struct bpf_prog *prog, const struct 
bpf_ext_analyzer_ops *ops,
        if (ret < 0)
                goto skip_full_check;
 
-       env->allow_ptr_leaks = capable(CAP_SYS_ADMIN);
+       env->allow_ptr_leaks = prog->priv_cap_sys_admin;
 
        ret = do_check(env);
 
diff --git a/net/core/filter.c b/net/core/filter.c
index 9a37860a80fc78..dc020d40bb770a 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -1100,7 +1100,7 @@ int bpf_prog_create(struct bpf_prog **pfp, struct 
sock_fprog_kern *fprog)
        if (!bpf_check_basics_ok(fprog->filter, fprog->len))
                return -EINVAL;
 
-       fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
+       fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0, false);
        if (!fp)
                return -ENOMEM;
 
@@ -1147,7 +1147,7 @@ int bpf_prog_create_from_user(struct bpf_prog **pfp, 
struct sock_fprog *fprog,
        if (!bpf_check_basics_ok(fprog->filter, fprog->len))
                return -EINVAL;
 
-       fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
+       fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0, false);
        if (!fp)
                return -ENOMEM;
 
@@ -1249,7 +1249,7 @@ struct bpf_prog *__get_filter(struct sock_fprog *fprog, 
struct sock *sk)
        if (!bpf_check_basics_ok(fprog->filter, fprog->len))
                return ERR_PTR(-EINVAL);
 
-       prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
+       prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0, false);
        if (!prog)
                return ERR_PTR(-ENOMEM);
 
-- 
2.9.3

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