kernel/bpf/verifier.c

86  * Meaning that this reg is a pointer to stack plus known immediate constant.
1319 	/* update known max for given subprogram */
1575  *     # Find outermost loop entry known for n
1772  * known to have the value @imm.
4617  * known to contain a variable offset.
4746  * respective stack slots. If all the stack values are known to be zeros, then
6994 			/* b/h/w load zero-extends, mark upper bits as known 0 */
7199 		 * arg 1. This can be relaxed on a case by case basis for known
8003  * is some statically known limit on number of iterations (e.g., if there is
8757 			 * map_key, so that it's verified and known before
8843 			verbose(env, "R%d is not a known constant'\n",
11177 	 * arguments, we resolve it to a known kfunc_ptr_arg_type.
11763 					verbose(env, "R%d must be a known constant\n", regno);
12130 					verbose(env, "R%d must be a known constant\n", regno + 1);
12737 	bool known = tnum_is_const(reg->var_off);
12741 	if (known && (val >= BPF_MAX_VAR_OFF || val <= -BPF_MAX_VAR_OFF)) {
12941 	 * Also, when register is a known constant, we rewrite register-based
13099 	bool known = tnum_is_const(off_reg->var_off);
13111 	if ((known && (smin_val != smax_val || umin_val != umax_val)) ||
13154 		if (known)
13158 		/* smin_val represents the known value */
13159 		if (known && smin_val == 0 && opcode == BPF_ADD)
13193 		if (known && (ptr_reg->off + smin_val ==
13255 		if (known && (ptr_reg->off - smin_val ==
13268 		/* A new variable offset is created.  If the subtrahend is known
13776 	 * 2) it's known negative, thus the unsigned bounds capture the
13780 	 * If the value in dst_reg is known nonnegative, then again the
13807 	 * 2) it's known negative, thus the unsigned bounds capture the
13811 	 * If the value in dst_reg is known nonnegative, then again the
14097 		/* Pretend the src is a reg with a known value, since we only
14432 	 * dst_reg->off is known < MAX_PACKET_OFF, therefore it fits in a u16.
14920 		 * known-zero, because we don't allow pointer arithmetic on
15671 		verbose(env, "%s the register R%d is not a known value (%s)\n",
15878 		/* For functions that invoke callbacks it is not known how many times
16977  * all states stored in state_list are known to be valid, since
20623 	/* callback start is known only after patching */