Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2021-06-28

The following pull-request contains BPF updates for your *net-next* tree.

We've added 37 non-merge commits during the last 12 day(s) which contain
a total of 56 files changed, 394 insertions(+), 380 deletions(-).

The main changes are:

1) XDP driver RCU cleanups, from Toke Høiland-Jørgensen and Paul E. McKenney.

2) Fix bpf_skb_change_proto() IPv4/v6 GSO handling, from Maciej Żenczykowski.

3) Fix false positive kmemleak report for BPF ringbuf alloc, from Rustam Kovhaev.

4) Fix x86 JIT's extable offset calculation for PROBE_LDX NULL, from Ravi Bangoria.

5) Enable libbpf fallback probing with tracing under RHEL7, from Jonathan Edwards.

6) Clean up x86 JIT to remove unused cnt tracking from EMIT macro, from Jiri Olsa.

7) Netlink cleanups for libbpf to please Coverity, from Kumar Kartikeya Dwivedi.

8) Allow to retrieve ancestor cgroup id in tracing programs, from Namhyung Kim.

9) Fix lirc BPF program query to use user-provided prog_cnt, from Sean Young.

10) Add initial libbpf doc including generated kdoc for its API, from Grant Seltzer.

11) Make xdp_rxq_info_unreg_mem_model() more robust, from Jakub Kicinski.

12) Fix up bpfilter startup log-level to info level, from Gary Lin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 33 deletions

diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index 2a2e290fa5d8..e835164189f1 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -31,7 +31,7 @@ static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len)
 }
 
 #define EMIT(bytes, len) \
-	do { prog = emit_code(prog, bytes, len); cnt += len; } while (0)
+	do { prog = emit_code(prog, bytes, len); } while (0)
 
 #define EMIT1(b1)		EMIT(b1, 1)
 #define EMIT2(b1, b2)		EMIT((b1) + ((b2) << 8), 2)
@@ -239,7 +239,6 @@ struct jit_context {
 static void push_callee_regs(u8 **pprog, bool *callee_regs_used)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 
 	if (callee_regs_used[0])
 		EMIT1(0x53);         /* push rbx */
@@ -255,7 +254,6 @@ static void push_callee_regs(u8 **pprog, bool *callee_regs_used)
 static void pop_callee_regs(u8 **pprog, bool *callee_regs_used)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 
 	if (callee_regs_used[3])
 		EMIT2(0x41, 0x5F);   /* pop r15 */
@@ -277,13 +275,12 @@ static void emit_prologue(u8 **pprog, u32 stack_depth, bool ebpf_from_cbpf,
 			  bool tail_call_reachable, bool is_subprog)
 {
 	u8 *prog = *pprog;
-	int cnt = X86_PATCH_SIZE;
 
 	/* BPF trampoline can be made to work without these nops,
 	 * but let's waste 5 bytes for now and optimize later
 	 */
-	memcpy(prog, x86_nops[5], cnt);
-	prog += cnt;
+	memcpy(prog, x86_nops[5], X86_PATCH_SIZE);
+	prog += X86_PATCH_SIZE;
 	if (!ebpf_from_cbpf) {
 		if (tail_call_reachable && !is_subprog)
 			EMIT2(0x31, 0xC0); /* xor eax, eax */
@@ -303,7 +300,6 @@ static void emit_prologue(u8 **pprog, u32 stack_depth, bool ebpf_from_cbpf,
 static int emit_patch(u8 **pprog, void *func, void *ip, u8 opcode)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 	s64 offset;
 
 	offset = func - (ip + X86_PATCH_SIZE);
@@ -423,7 +419,6 @@ static void emit_bpf_tail_call_indirect(u8 **pprog, bool *callee_regs_used,
 	int off1 = 42;
 	int off2 = 31;
 	int off3 = 9;
-	int cnt = 0;
 
 	/* count the additional bytes used for popping callee regs from stack
 	 * that need to be taken into account for each of the offsets that
@@ -513,7 +508,6 @@ static void emit_bpf_tail_call_direct(struct bpf_jit_poke_descriptor *poke,
 	int pop_bytes = 0;
 	int off1 = 20;
 	int poke_off;
-	int cnt = 0;
 
 	/* count the additional bytes used for popping callee regs to stack
 	 * that need to be taken into account for jump offset that is used for
@@ -615,7 +609,6 @@ static void emit_mov_imm32(u8 **pprog, bool sign_propagate,
 {
 	u8 *prog = *pprog;
 	u8 b1, b2, b3;
-	int cnt = 0;
 
 	/*
 	 * Optimization: if imm32 is positive, use 'mov %eax, imm32'
@@ -655,7 +648,6 @@ static void emit_mov_imm64(u8 **pprog, u32 dst_reg,
 			   const u32 imm32_hi, const u32 imm32_lo)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 
 	if (is_uimm32(((u64)imm32_hi << 32) | (u32)imm32_lo)) {
 		/*
@@ -678,7 +670,6 @@ static void emit_mov_imm64(u8 **pprog, u32 dst_reg,
 static void emit_mov_reg(u8 **pprog, bool is64, u32 dst_reg, u32 src_reg)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 
 	if (is64) {
 		/* mov dst, src */
@@ -697,7 +688,6 @@ static void emit_mov_reg(u8 **pprog, bool is64, u32 dst_reg, u32 src_reg)
 static void emit_insn_suffix(u8 **pprog, u32 ptr_reg, u32 val_reg, int off)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 
 	if (is_imm8(off)) {
 		/* 1-byte signed displacement.
@@ -720,7 +710,6 @@ static void emit_insn_suffix(u8 **pprog, u32 ptr_reg, u32 val_reg, int off)
 static void maybe_emit_mod(u8 **pprog, u32 dst_reg, u32 src_reg, bool is64)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 
 	if (is64)
 		EMIT1(add_2mod(0x48, dst_reg, src_reg));
@@ -733,7 +722,6 @@ static void maybe_emit_mod(u8 **pprog, u32 dst_reg, u32 src_reg, bool is64)
 static void emit_ldx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 
 	switch (size) {
 	case BPF_B:
@@ -764,7 +752,6 @@ static void emit_ldx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off)
 static void emit_stx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 
 	switch (size) {
 	case BPF_B:
@@ -799,7 +786,6 @@ static int emit_atomic(u8 **pprog, u8 atomic_op,
 		       u32 dst_reg, u32 src_reg, s16 off, u8 bpf_size)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 
 	EMIT1(0xF0); /* lock prefix */
 
@@ -869,10 +855,10 @@ static void detect_reg_usage(struct bpf_insn *insn, int insn_cnt,
 	}
 }
 
-static int emit_nops(u8 **pprog, int len)
+static void emit_nops(u8 **pprog, int len)
 {
 	u8 *prog = *pprog;
-	int i, noplen, cnt = 0;
+	int i, noplen;
 
 	while (len > 0) {
 		noplen = len;
@@ -886,8 +872,6 @@ static int emit_nops(u8 **pprog, int len)
 	}
 
 	*pprog = prog;
-
-	return cnt;
 }
 
 #define INSN_SZ_DIFF (((addrs[i] - addrs[i - 1]) - (prog - temp)))
@@ -902,7 +886,7 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 	bool tail_call_seen = false;
 	bool seen_exit = false;
 	u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY];
-	int i, cnt = 0, excnt = 0;
+	int i, excnt = 0;
 	int ilen, proglen = 0;
 	u8 *prog = temp;
 	int err;
@@ -1297,7 +1281,7 @@ st:			if (is_imm8(insn->off))
 			emit_ldx(&prog, BPF_SIZE(insn->code), dst_reg, src_reg, insn->off);
 			if (BPF_MODE(insn->code) == BPF_PROBE_MEM) {
 				struct exception_table_entry *ex;
-				u8 *_insn = image + proglen;
+				u8 *_insn = image + proglen + (start_of_ldx - temp);
 				s64 delta;
 
 				/* populate jmp_offset for JMP above */
@@ -1576,7 +1560,7 @@ emit_cond_jmp:		/* Convert BPF opcode to x86 */
 						       nops);
 						return -EFAULT;
 					}
-					cnt += emit_nops(&prog, nops);
+					emit_nops(&prog, nops);
 				}
 				EMIT2(jmp_cond, jmp_offset);
 			} else if (is_simm32(jmp_offset)) {
@@ -1622,7 +1606,7 @@ emit_cond_jmp:		/* Convert BPF opcode to x86 */
 						       nops);
 						return -EFAULT;
 					}
-					cnt += emit_nops(&prog, nops);
+					emit_nops(&prog, nops);
 				}
 				break;
 			}
@@ -1647,7 +1631,7 @@ emit_jmp:
 						       nops);
 						return -EFAULT;
 					}
-					cnt += emit_nops(&prog, INSN_SZ_DIFF - 2);
+					emit_nops(&prog, INSN_SZ_DIFF - 2);
 				}
 				EMIT2(0xEB, jmp_offset);
 			} else if (is_simm32(jmp_offset)) {
@@ -1754,7 +1738,6 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
 {
 	u8 *prog = *pprog;
 	u8 *jmp_insn;
-	int cnt = 0;
 
 	/* arg1: mov rdi, progs[i] */
 	emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p);
@@ -1822,7 +1805,6 @@ static void emit_align(u8 **pprog, u32 align)
 static int emit_cond_near_jump(u8 **pprog, void *func, void *ip, u8 jmp_cond)
 {
 	u8 *prog = *pprog;
-	int cnt = 0;
 	s64 offset;
 
 	offset = func - (ip + 2 + 4);
@@ -1854,7 +1836,7 @@ static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog,
 			      u8 **branches)
 {
 	u8 *prog = *pprog;
-	int i, cnt = 0;
+	int i;
 
 	/* The first fmod_ret program will receive a garbage return value.
 	 * Set this to 0 to avoid confusing the program.
@@ -1950,7 +1932,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
 				struct bpf_tramp_progs *tprogs,
 				void *orig_call)
 {
-	int ret, i, cnt = 0, nr_args = m->nr_args;
+	int ret, i, nr_args = m->nr_args;
 	int stack_size = nr_args * 8;
 	struct bpf_tramp_progs *fentry = &tprogs[BPF_TRAMP_FENTRY];
 	struct bpf_tramp_progs *fexit = &tprogs[BPF_TRAMP_FEXIT];
@@ -2095,8 +2077,6 @@ static int emit_fallback_jump(u8 **pprog)
 	 */
 	err = emit_jump(&prog, __x86_indirect_thunk_rdx, prog);
 #else
-	int cnt = 0;
-
 	EMIT2(0xFF, 0xE2);	/* jmp rdx */
 #endif
 	*pprog = prog;
@@ -2106,7 +2086,7 @@ static int emit_fallback_jump(u8 **pprog)
 static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs)
 {
 	u8 *jg_reloc, *prog = *pprog;
-	int pivot, err, jg_bytes = 1, cnt = 0;
+	int pivot, err, jg_bytes = 1;
 	s64 jg_offset;
 
 	if (a == b) {