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Diffstat (limited to 'kernel/bpf/core.c')
-rw-r--r--kernel/bpf/core.c132
1 files changed, 112 insertions, 20 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 7949e8b8f94e..887e28408f98 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -94,6 +94,7 @@ 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;
+ fp->jit_requested = ebpf_jit_enabled();
INIT_LIST_HEAD_RCU(&fp->aux->ksym_lnode);
@@ -217,30 +218,40 @@ int bpf_prog_calc_tag(struct bpf_prog *fp)
return 0;
}
-static bool bpf_is_jmp_and_has_target(const struct bpf_insn *insn)
-{
- return BPF_CLASS(insn->code) == BPF_JMP &&
- /* Call and Exit are both special jumps with no
- * target inside the BPF instruction image.
- */
- BPF_OP(insn->code) != BPF_CALL &&
- BPF_OP(insn->code) != BPF_EXIT;
-}
-
static void bpf_adj_branches(struct bpf_prog *prog, u32 pos, u32 delta)
{
struct bpf_insn *insn = prog->insnsi;
u32 i, insn_cnt = prog->len;
+ bool pseudo_call;
+ u8 code;
+ int off;
for (i = 0; i < insn_cnt; i++, insn++) {
- if (!bpf_is_jmp_and_has_target(insn))
+ code = insn->code;
+ if (BPF_CLASS(code) != BPF_JMP)
+ continue;
+ if (BPF_OP(code) == BPF_EXIT)
continue;
+ if (BPF_OP(code) == BPF_CALL) {
+ if (insn->src_reg == BPF_PSEUDO_CALL)
+ pseudo_call = true;
+ else
+ continue;
+ } else {
+ pseudo_call = false;
+ }
+ off = pseudo_call ? insn->imm : insn->off;
/* Adjust offset of jmps if we cross boundaries. */
- if (i < pos && i + insn->off + 1 > pos)
- insn->off += delta;
- else if (i > pos + delta && i + insn->off + 1 <= pos + delta)
- insn->off -= delta;
+ if (i < pos && i + off + 1 > pos)
+ off += delta;
+ else if (i > pos + delta && i + off + 1 <= pos + delta)
+ off -= delta;
+
+ if (pseudo_call)
+ insn->imm = off;
+ else
+ insn->off = off;
}
}
@@ -711,7 +722,7 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
struct bpf_insn *insn;
int i, rewritten;
- if (!bpf_jit_blinding_enabled())
+ if (!bpf_jit_blinding_enabled(prog) || prog->blinded)
return prog;
clone = bpf_prog_clone_create(prog, GFP_USER);
@@ -753,13 +764,16 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
i += insn_delta;
}
+ clone->blinded = 1;
return clone;
}
#endif /* CONFIG_BPF_JIT */
/* Base function for offset calculation. Needs to go into .text section,
* therefore keeping it non-static as well; will also be used by JITs
- * anyway later on, so do not let the compiler omit it.
+ * anyway later on, so do not let the compiler omit it. This also needs
+ * to go into kallsyms for correlation from e.g. bpftool, so naming
+ * must not change.
*/
noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
{
@@ -775,8 +789,7 @@ EXPORT_SYMBOL_GPL(__bpf_call_base);
*
* Decode and execute eBPF instructions.
*/
-static unsigned int ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn,
- u64 *stack)
+static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack)
{
u64 tmp;
static const void *jumptable[256] = {
@@ -836,6 +849,7 @@ static unsigned int ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn,
[BPF_ALU64 | BPF_NEG] = &&ALU64_NEG,
/* Call instruction */
[BPF_JMP | BPF_CALL] = &&JMP_CALL,
+ [BPF_JMP | BPF_CALL_ARGS] = &&JMP_CALL_ARGS,
[BPF_JMP | BPF_TAIL_CALL] = &&JMP_TAIL_CALL,
/* Jumps */
[BPF_JMP | BPF_JA] = &&JMP_JA,
@@ -1026,6 +1040,13 @@ select_insn:
BPF_R4, BPF_R5);
CONT;
+ JMP_CALL_ARGS:
+ BPF_R0 = (__bpf_call_base_args + insn->imm)(BPF_R1, BPF_R2,
+ BPF_R3, BPF_R4,
+ BPF_R5,
+ insn + insn->off + 1);
+ CONT;
+
JMP_TAIL_CALL: {
struct bpf_map *map = (struct bpf_map *) (unsigned long) BPF_R2;
struct bpf_array *array = container_of(map, struct bpf_array, map);
@@ -1298,6 +1319,23 @@ static unsigned int PROG_NAME(stack_size)(const void *ctx, const struct bpf_insn
return ___bpf_prog_run(regs, insn, stack); \
}
+#define PROG_NAME_ARGS(stack_size) __bpf_prog_run_args##stack_size
+#define DEFINE_BPF_PROG_RUN_ARGS(stack_size) \
+static u64 PROG_NAME_ARGS(stack_size)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5, \
+ const struct bpf_insn *insn) \
+{ \
+ u64 stack[stack_size / sizeof(u64)]; \
+ u64 regs[MAX_BPF_REG]; \
+\
+ FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \
+ BPF_R1 = r1; \
+ BPF_R2 = r2; \
+ BPF_R3 = r3; \
+ BPF_R4 = r4; \
+ BPF_R5 = r5; \
+ return ___bpf_prog_run(regs, insn, stack); \
+}
+
#define EVAL1(FN, X) FN(X)
#define EVAL2(FN, X, Y...) FN(X) EVAL1(FN, Y)
#define EVAL3(FN, X, Y...) FN(X) EVAL2(FN, Y)
@@ -1309,6 +1347,10 @@ EVAL6(DEFINE_BPF_PROG_RUN, 32, 64, 96, 128, 160, 192);
EVAL6(DEFINE_BPF_PROG_RUN, 224, 256, 288, 320, 352, 384);
EVAL4(DEFINE_BPF_PROG_RUN, 416, 448, 480, 512);
+EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 32, 64, 96, 128, 160, 192);
+EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 224, 256, 288, 320, 352, 384);
+EVAL4(DEFINE_BPF_PROG_RUN_ARGS, 416, 448, 480, 512);
+
#define PROG_NAME_LIST(stack_size) PROG_NAME(stack_size),
static unsigned int (*interpreters[])(const void *ctx,
@@ -1317,6 +1359,24 @@ EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192)
EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384)
EVAL4(PROG_NAME_LIST, 416, 448, 480, 512)
};
+#undef PROG_NAME_LIST
+#define PROG_NAME_LIST(stack_size) PROG_NAME_ARGS(stack_size),
+static u64 (*interpreters_args[])(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5,
+ const struct bpf_insn *insn) = {
+EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192)
+EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384)
+EVAL4(PROG_NAME_LIST, 416, 448, 480, 512)
+};
+#undef PROG_NAME_LIST
+
+void bpf_patch_call_args(struct bpf_insn *insn, u32 stack_depth)
+{
+ stack_depth = max_t(u32, stack_depth, 1);
+ insn->off = (s16) insn->imm;
+ insn->imm = interpreters_args[(round_up(stack_depth, 32) / 32) - 1] -
+ __bpf_call_base_args;
+ insn->code = BPF_JMP | BPF_CALL_ARGS;
+}
#else
static unsigned int __bpf_prog_ret0(const void *ctx,
@@ -1329,6 +1389,9 @@ static unsigned int __bpf_prog_ret0(const void *ctx,
bool bpf_prog_array_compatible(struct bpf_array *array,
const struct bpf_prog *fp)
{
+ if (fp->kprobe_override)
+ return false;
+
if (!array->owner_prog_type) {
/* There's no owner yet where we could check for
* compatibility.
@@ -1481,6 +1544,8 @@ int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *progs,
rcu_read_lock();
prog = rcu_dereference(progs)->progs;
for (; *prog; prog++) {
+ if (*prog == &dummy_bpf_prog.prog)
+ continue;
id = (*prog)->aux->id;
if (copy_to_user(prog_ids + i, &id, sizeof(id))) {
rcu_read_unlock();
@@ -1564,14 +1629,41 @@ int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array,
return 0;
}
+int bpf_prog_array_copy_info(struct bpf_prog_array __rcu *array,
+ __u32 __user *prog_ids, u32 request_cnt,
+ __u32 __user *prog_cnt)
+{
+ u32 cnt = 0;
+
+ if (array)
+ cnt = bpf_prog_array_length(array);
+
+ if (copy_to_user(prog_cnt, &cnt, sizeof(cnt)))
+ return -EFAULT;
+
+ /* return early if user requested only program count or nothing to copy */
+ if (!request_cnt || !cnt)
+ return 0;
+
+ return bpf_prog_array_copy_to_user(array, prog_ids, request_cnt);
+}
+
static void bpf_prog_free_deferred(struct work_struct *work)
{
struct bpf_prog_aux *aux;
+ int i;
aux = container_of(work, struct bpf_prog_aux, work);
if (bpf_prog_is_dev_bound(aux))
bpf_prog_offload_destroy(aux->prog);
- bpf_jit_free(aux->prog);
+ for (i = 0; i < aux->func_cnt; i++)
+ bpf_jit_free(aux->func[i]);
+ if (aux->func_cnt) {
+ kfree(aux->func);
+ bpf_prog_unlock_free(aux->prog);
+ } else {
+ bpf_jit_free(aux->prog);
+ }
}
/* Free internal BPF program */
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-16 04:11:55 +0000