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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-01-20 14:01:31 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-01-20 14:01:31 -0300
commitb4b7ff4b08e691656c9d77c758fc355833128ac0 (patch)
tree82fcb00e6b918026dc9f2d1f05ed8eee83874cc0 /kernel/bpf/core.c
parent35acfa0fc609f2a2cd95cef4a6a9c3a5c38f1778 (diff)
Linux-libre 4.4-gnupck-4.4-gnu
Diffstat (limited to 'kernel/bpf/core.c')
-rw-r--r--kernel/bpf/core.c33
1 files changed, 32 insertions, 1 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 67c380cfa..334b1bdd5 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -82,6 +82,8 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
if (fp == NULL)
return NULL;
+ kmemcheck_annotate_bitfield(fp, meta);
+
aux = kzalloc(sizeof(*aux), GFP_KERNEL | gfp_extra_flags);
if (aux == NULL) {
vfree(fp);
@@ -90,6 +92,7 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
fp->pages = size / PAGE_SIZE;
fp->aux = aux;
+ fp->aux->prog = fp;
return fp;
}
@@ -110,8 +113,11 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
if (fp != NULL) {
+ kmemcheck_annotate_bitfield(fp, meta);
+
memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
fp->pages = size / PAGE_SIZE;
+ fp->aux->prog = fp;
/* We keep fp->aux from fp_old around in the new
* reallocated structure.
@@ -722,11 +728,36 @@ void bpf_prog_free(struct bpf_prog *fp)
struct bpf_prog_aux *aux = fp->aux;
INIT_WORK(&aux->work, bpf_prog_free_deferred);
- aux->prog = fp;
schedule_work(&aux->work);
}
EXPORT_SYMBOL_GPL(bpf_prog_free);
+/* RNG for unpriviledged user space with separated state from prandom_u32(). */
+static DEFINE_PER_CPU(struct rnd_state, bpf_user_rnd_state);
+
+void bpf_user_rnd_init_once(void)
+{
+ prandom_init_once(&bpf_user_rnd_state);
+}
+
+u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ /* Should someone ever have the rather unwise idea to use some
+ * of the registers passed into this function, then note that
+ * this function is called from native eBPF and classic-to-eBPF
+ * transformations. Register assignments from both sides are
+ * different, f.e. classic always sets fn(ctx, A, X) here.
+ */
+ struct rnd_state *state;
+ u32 res;
+
+ state = &get_cpu_var(bpf_user_rnd_state);
+ res = prandom_u32_state(state);
+ put_cpu_var(state);
+
+ return res;
+}
+
/* Weak definitions of helper functions in case we don't have bpf syscall. */
const struct bpf_func_proto bpf_map_lookup_elem_proto __weak;
const struct bpf_func_proto bpf_map_update_elem_proto __weak;