Merge branch 'libbpf:master' into master

thiagoftsm · web-flow · commit 89aecd2188fa · 2024-05-13T01:33:50.000Z
diff --git a/CHECKPOINT-COMMIT b/CHECKPOINT-COMMIT
@@ -1 +1 @@
-0737df6de94661ae55fd3343ce9abec32c687e62
+009367099eb61a4fc2af44d4eb06b6b4de7de6db
diff --git a/src/bpf_core_read.h b/src/bpf_core_read.h
@@ -104,6 +104,7 @@ enum bpf_enum_value_kind {
 	case 2: val = *(const unsigned short *)p; break;		      \
 	case 4: val = *(const unsigned int *)p; break;			      \
 	case 8: val = *(const unsigned long long *)p; break;		      \
+	default: val = 0; break;					      \
 	}								      \
 	val <<= __CORE_RELO(s, field, LSHIFT_U64);			      \
 	if (__CORE_RELO(s, field, SIGNED))				      \
diff --git a/src/bpf_helpers.h b/src/bpf_helpers.h
@@ -186,10 +186,21 @@ enum libbpf_tristate {
 #define __kptr __attribute__((btf_type_tag("kptr")))
 #define __percpu_kptr __attribute__((btf_type_tag("percpu_kptr")))
 
-#define bpf_ksym_exists(sym) ({									\
-	_Static_assert(!__builtin_constant_p(!!sym), #sym " should be marked as __weak");	\
-	!!sym;											\
+#if defined (__clang__)
+#define bpf_ksym_exists(sym) ({						\
+	_Static_assert(!__builtin_constant_p(!!sym),			\
+		       #sym " should be marked as __weak");		\
+	!!sym;								\
 })
+#elif __GNUC__ > 8
+#define bpf_ksym_exists(sym) ({						\
+	_Static_assert(__builtin_has_attribute (*sym, __weak__),	\
+		       #sym " should be marked as __weak");		\
+	!!sym;								\
+})
+#else
+#define bpf_ksym_exists(sym) !!sym
+#endif
 
 #define __arg_ctx __attribute__((btf_decl_tag("arg:ctx")))
 #define __arg_nonnull __attribute((btf_decl_tag("arg:nonnull")))
diff --git a/src/bpf_tracing.h b/src/bpf_tracing.h
@@ -633,18 +633,18 @@ struct pt_regs;
 #endif
 
 #define ___bpf_ctx_cast0()            ctx
-#define ___bpf_ctx_cast1(x)           ___bpf_ctx_cast0(), (void *)ctx[0]
-#define ___bpf_ctx_cast2(x, args...)  ___bpf_ctx_cast1(args), (void *)ctx[1]
-#define ___bpf_ctx_cast3(x, args...)  ___bpf_ctx_cast2(args), (void *)ctx[2]
-#define ___bpf_ctx_cast4(x, args...)  ___bpf_ctx_cast3(args), (void *)ctx[3]
-#define ___bpf_ctx_cast5(x, args...)  ___bpf_ctx_cast4(args), (void *)ctx[4]
-#define ___bpf_ctx_cast6(x, args...)  ___bpf_ctx_cast5(args), (void *)ctx[5]
-#define ___bpf_ctx_cast7(x, args...)  ___bpf_ctx_cast6(args), (void *)ctx[6]
-#define ___bpf_ctx_cast8(x, args...)  ___bpf_ctx_cast7(args), (void *)ctx[7]
-#define ___bpf_ctx_cast9(x, args...)  ___bpf_ctx_cast8(args), (void *)ctx[8]
-#define ___bpf_ctx_cast10(x, args...) ___bpf_ctx_cast9(args), (void *)ctx[9]
-#define ___bpf_ctx_cast11(x, args...) ___bpf_ctx_cast10(args), (void *)ctx[10]
-#define ___bpf_ctx_cast12(x, args...) ___bpf_ctx_cast11(args), (void *)ctx[11]
+#define ___bpf_ctx_cast1(x)           ___bpf_ctx_cast0(), ctx[0]
+#define ___bpf_ctx_cast2(x, args...)  ___bpf_ctx_cast1(args), ctx[1]
+#define ___bpf_ctx_cast3(x, args...)  ___bpf_ctx_cast2(args), ctx[2]
+#define ___bpf_ctx_cast4(x, args...)  ___bpf_ctx_cast3(args), ctx[3]
+#define ___bpf_ctx_cast5(x, args...)  ___bpf_ctx_cast4(args), ctx[4]
+#define ___bpf_ctx_cast6(x, args...)  ___bpf_ctx_cast5(args), ctx[5]
+#define ___bpf_ctx_cast7(x, args...)  ___bpf_ctx_cast6(args), ctx[6]
+#define ___bpf_ctx_cast8(x, args...)  ___bpf_ctx_cast7(args), ctx[7]
+#define ___bpf_ctx_cast9(x, args...)  ___bpf_ctx_cast8(args), ctx[8]
+#define ___bpf_ctx_cast10(x, args...) ___bpf_ctx_cast9(args), ctx[9]
+#define ___bpf_ctx_cast11(x, args...) ___bpf_ctx_cast10(args), ctx[10]
+#define ___bpf_ctx_cast12(x, args...) ___bpf_ctx_cast11(args), ctx[11]
 #define ___bpf_ctx_cast(args...)      ___bpf_apply(___bpf_ctx_cast, ___bpf_narg(args))(args)
 
 /*
@@ -786,14 +786,14 @@ ____##name(unsigned long long *ctx ___bpf_ctx_decl(args))
 struct pt_regs;
 
 #define ___bpf_kprobe_args0()           ctx
-#define ___bpf_kprobe_args1(x)          ___bpf_kprobe_args0(), (void *)PT_REGS_PARM1(ctx)
-#define ___bpf_kprobe_args2(x, args...) ___bpf_kprobe_args1(args), (void *)PT_REGS_PARM2(ctx)
-#define ___bpf_kprobe_args3(x, args...) ___bpf_kprobe_args2(args), (void *)PT_REGS_PARM3(ctx)
-#define ___bpf_kprobe_args4(x, args...) ___bpf_kprobe_args3(args), (void *)PT_REGS_PARM4(ctx)
-#define ___bpf_kprobe_args5(x, args...) ___bpf_kprobe_args4(args), (void *)PT_REGS_PARM5(ctx)
-#define ___bpf_kprobe_args6(x, args...) ___bpf_kprobe_args5(args), (void *)PT_REGS_PARM6(ctx)
-#define ___bpf_kprobe_args7(x, args...) ___bpf_kprobe_args6(args), (void *)PT_REGS_PARM7(ctx)
-#define ___bpf_kprobe_args8(x, args...) ___bpf_kprobe_args7(args), (void *)PT_REGS_PARM8(ctx)
+#define ___bpf_kprobe_args1(x)          ___bpf_kprobe_args0(), (unsigned long long)PT_REGS_PARM1(ctx)
+#define ___bpf_kprobe_args2(x, args...) ___bpf_kprobe_args1(args), (unsigned long long)PT_REGS_PARM2(ctx)
+#define ___bpf_kprobe_args3(x, args...) ___bpf_kprobe_args2(args), (unsigned long long)PT_REGS_PARM3(ctx)
+#define ___bpf_kprobe_args4(x, args...) ___bpf_kprobe_args3(args), (unsigned long long)PT_REGS_PARM4(ctx)
+#define ___bpf_kprobe_args5(x, args...) ___bpf_kprobe_args4(args), (unsigned long long)PT_REGS_PARM5(ctx)
+#define ___bpf_kprobe_args6(x, args...) ___bpf_kprobe_args5(args), (unsigned long long)PT_REGS_PARM6(ctx)
+#define ___bpf_kprobe_args7(x, args...) ___bpf_kprobe_args6(args), (unsigned long long)PT_REGS_PARM7(ctx)
+#define ___bpf_kprobe_args8(x, args...) ___bpf_kprobe_args7(args), (unsigned long long)PT_REGS_PARM8(ctx)
 #define ___bpf_kprobe_args(args...)     ___bpf_apply(___bpf_kprobe_args, ___bpf_narg(args))(args)
 
 /*
@@ -821,7 +821,7 @@ static __always_inline typeof(name(0))					    \
 ____##name(struct pt_regs *ctx, ##args)
 
 #define ___bpf_kretprobe_args0()       ctx
-#define ___bpf_kretprobe_args1(x)      ___bpf_kretprobe_args0(), (void *)PT_REGS_RC(ctx)
+#define ___bpf_kretprobe_args1(x)      ___bpf_kretprobe_args0(), (unsigned long long)PT_REGS_RC(ctx)
 #define ___bpf_kretprobe_args(args...) ___bpf_apply(___bpf_kretprobe_args, ___bpf_narg(args))(args)
 
 /*
@@ -845,24 +845,24 @@ static __always_inline typeof(name(0)) ____##name(struct pt_regs *ctx, ##args)
 
 /* If kernel has CONFIG_ARCH_HAS_SYSCALL_WRAPPER, read pt_regs directly */
 #define ___bpf_syscall_args0()           ctx
-#define ___bpf_syscall_args1(x)          ___bpf_syscall_args0(), (void *)PT_REGS_PARM1_SYSCALL(regs)
-#define ___bpf_syscall_args2(x, args...) ___bpf_syscall_args1(args), (void *)PT_REGS_PARM2_SYSCALL(regs)
-#define ___bpf_syscall_args3(x, args...) ___bpf_syscall_args2(args), (void *)PT_REGS_PARM3_SYSCALL(regs)
-#define ___bpf_syscall_args4(x, args...) ___bpf_syscall_args3(args), (void *)PT_REGS_PARM4_SYSCALL(regs)
-#define ___bpf_syscall_args5(x, args...) ___bpf_syscall_args4(args), (void *)PT_REGS_PARM5_SYSCALL(regs)
-#define ___bpf_syscall_args6(x, args...) ___bpf_syscall_args5(args), (void *)PT_REGS_PARM6_SYSCALL(regs)
-#define ___bpf_syscall_args7(x, args...) ___bpf_syscall_args6(args), (void *)PT_REGS_PARM7_SYSCALL(regs)
+#define ___bpf_syscall_args1(x)          ___bpf_syscall_args0(), (unsigned long long)PT_REGS_PARM1_SYSCALL(regs)
+#define ___bpf_syscall_args2(x, args...) ___bpf_syscall_args1(args), (unsigned long long)PT_REGS_PARM2_SYSCALL(regs)
+#define ___bpf_syscall_args3(x, args...) ___bpf_syscall_args2(args), (unsigned long long)PT_REGS_PARM3_SYSCALL(regs)
+#define ___bpf_syscall_args4(x, args...) ___bpf_syscall_args3(args), (unsigned long long)PT_REGS_PARM4_SYSCALL(regs)
+#define ___bpf_syscall_args5(x, args...) ___bpf_syscall_args4(args), (unsigned long long)PT_REGS_PARM5_SYSCALL(regs)
+#define ___bpf_syscall_args6(x, args...) ___bpf_syscall_args5(args), (unsigned long long)PT_REGS_PARM6_SYSCALL(regs)
+#define ___bpf_syscall_args7(x, args...) ___bpf_syscall_args6(args), (unsigned long long)PT_REGS_PARM7_SYSCALL(regs)
 #define ___bpf_syscall_args(args...)     ___bpf_apply(___bpf_syscall_args, ___bpf_narg(args))(args)
 
 /* If kernel doesn't have CONFIG_ARCH_HAS_SYSCALL_WRAPPER, we have to BPF_CORE_READ from pt_regs */
 #define ___bpf_syswrap_args0()           ctx
-#define ___bpf_syswrap_args1(x)          ___bpf_syswrap_args0(), (void *)PT_REGS_PARM1_CORE_SYSCALL(regs)
-#define ___bpf_syswrap_args2(x, args...) ___bpf_syswrap_args1(args), (void *)PT_REGS_PARM2_CORE_SYSCALL(regs)
-#define ___bpf_syswrap_args3(x, args...) ___bpf_syswrap_args2(args), (void *)PT_REGS_PARM3_CORE_SYSCALL(regs)
-#define ___bpf_syswrap_args4(x, args...) ___bpf_syswrap_args3(args), (void *)PT_REGS_PARM4_CORE_SYSCALL(regs)
-#define ___bpf_syswrap_args5(x, args...) ___bpf_syswrap_args4(args), (void *)PT_REGS_PARM5_CORE_SYSCALL(regs)
-#define ___bpf_syswrap_args6(x, args...) ___bpf_syswrap_args5(args), (void *)PT_REGS_PARM6_CORE_SYSCALL(regs)
-#define ___bpf_syswrap_args7(x, args...) ___bpf_syswrap_args6(args), (void *)PT_REGS_PARM7_CORE_SYSCALL(regs)
+#define ___bpf_syswrap_args1(x)          ___bpf_syswrap_args0(), (unsigned long long)PT_REGS_PARM1_CORE_SYSCALL(regs)
+#define ___bpf_syswrap_args2(x, args...) ___bpf_syswrap_args1(args), (unsigned long long)PT_REGS_PARM2_CORE_SYSCALL(regs)
+#define ___bpf_syswrap_args3(x, args...) ___bpf_syswrap_args2(args), (unsigned long long)PT_REGS_PARM3_CORE_SYSCALL(regs)
+#define ___bpf_syswrap_args4(x, args...) ___bpf_syswrap_args3(args), (unsigned long long)PT_REGS_PARM4_CORE_SYSCALL(regs)
+#define ___bpf_syswrap_args5(x, args...) ___bpf_syswrap_args4(args), (unsigned long long)PT_REGS_PARM5_CORE_SYSCALL(regs)
+#define ___bpf_syswrap_args6(x, args...) ___bpf_syswrap_args5(args), (unsigned long long)PT_REGS_PARM6_CORE_SYSCALL(regs)
+#define ___bpf_syswrap_args7(x, args...) ___bpf_syswrap_args6(args), (unsigned long long)PT_REGS_PARM7_CORE_SYSCALL(regs)
 #define ___bpf_syswrap_args(args...)     ___bpf_apply(___bpf_syswrap_args, ___bpf_narg(args))(args)
 
 /*
diff --git a/src/libbpf.c b/src/libbpf.c
@@ -1152,22 +1152,15 @@ static int bpf_map__init_kern_struct_ops(struct bpf_map *map)
 				return -ENOTSUP;
 			}
 
-			prog = st_ops->progs[i];
-			if (prog) {
+			if (st_ops->progs[i]) {
 				/* If we had declaratively set struct_ops callback, we need to
-				 * first validate that it's actually a struct_ops program.
-				 * And then force its autoload to false, because it doesn't have
+				 * force its autoload to false, because it doesn't have
 				 * a chance of succeeding from POV of the current struct_ops map.
 				 * If this program is still referenced somewhere else, though,
 				 * then bpf_object_adjust_struct_ops_autoload() will update its
 				 * autoload accordingly.
 				 */
-				if (!is_valid_st_ops_program(obj, prog)) {
-					pr_warn("struct_ops init_kern %s: member %s is declaratively assigned a non-struct_ops program\n",
-						map->name, mname);
-					return -EINVAL;
-				}
-				prog->autoload = false;
+				st_ops->progs[i]->autoload = false;
 				st_ops->progs[i] = NULL;
 			}
 
@@ -1200,11 +1193,19 @@ static int bpf_map__init_kern_struct_ops(struct bpf_map *map)
 		}
 
 		if (btf_is_ptr(mtype)) {
-			/* Update the value from the shadow type */
 			prog = *(void **)mdata;
+			/* just like for !kern_member case above, reset declaratively
+			 * set (at compile time) program's autload to false,
+			 * if user replaced it with another program or NULL
+			 */
+			if (st_ops->progs[i] && st_ops->progs[i] != prog)
+				st_ops->progs[i]->autoload = false;
+
+			/* Update the value from the shadow type */
 			st_ops->progs[i] = prog;
 			if (!prog)
 				continue;
+
 			if (!is_valid_st_ops_program(obj, prog)) {
 				pr_warn("struct_ops init_kern %s: member %s is not a struct_ops program\n",
 					map->name, mname);
@@ -7371,14 +7372,27 @@ static int bpf_object_load_prog(struct bpf_object *obj, struct bpf_program *prog
 	__u32 log_level = prog->log_level;
 	int ret, err;
 
-	if (prog->type == BPF_PROG_TYPE_UNSPEC) {
+	/* Be more helpful by rejecting programs that can't be validated early
+	 * with more meaningful and actionable error message.
+	 */
+	switch (prog->type) {
+	case BPF_PROG_TYPE_UNSPEC:
 		/*
 		 * The program type must be set.  Most likely we couldn't find a proper
 		 * section definition at load time, and thus we didn't infer the type.
 		 */
 		pr_warn("prog '%s': missing BPF prog type, check ELF section name '%s'\n",
 			prog->name, prog->sec_name);
 		return -EINVAL;
+	case BPF_PROG_TYPE_STRUCT_OPS:
+		if (prog->attach_btf_id == 0) {
+			pr_warn("prog '%s': SEC(\"struct_ops\") program isn't referenced anywhere, did you forget to use it?\n",
+				prog->name);
+			return -EINVAL;
+		}
+		break;
+	default:
+		break;
 	}
 
 	if (!insns || !insns_cnt)
@@ -11579,7 +11593,7 @@ static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, stru
 
 	n = sscanf(spec, "%m[a-zA-Z0-9_.*?]", &pattern);
 	if (n < 1) {
-		pr_warn("kprobe multi pattern is invalid: %s\n", pattern);
+		pr_warn("kprobe multi pattern is invalid: %s\n", spec);
 		return -EINVAL;
 	}
 
@@ -11605,7 +11619,7 @@ static int attach_kprobe_session(const struct bpf_program *prog, long cookie,
 	spec = prog->sec_name + sizeof("kprobe.session/") - 1;
 	n = sscanf(spec, "%m[a-zA-Z0-9_.*?]", &pattern);
 	if (n < 1) {
-		pr_warn("kprobe session pattern is invalid: %s\n", pattern);
+		pr_warn("kprobe session pattern is invalid: %s\n", spec);
 		return -EINVAL;
 	}
 
diff --git a/src/ringbuf.c b/src/ringbuf.c
@@ -301,7 +301,7 @@ int ring_buffer__consume_n(struct ring_buffer *rb, size_t n)
 		if (n == 0)
 			break;
 	}
-	return res;
+	return res > INT_MAX ? INT_MAX : res;
 }
 
 /* Consume available ring buffer(s) data without event polling.
@@ -405,7 +405,7 @@ int ring__map_fd(const struct ring *r)
 
 int ring__consume_n(struct ring *r, size_t n)
 {
-	int res;
+	int64_t res;
 
 	res = ringbuf_process_ring(r, n);
 	if (res < 0)
diff --git a/src/str_error.c b/src/str_error.c
@@ -2,6 +2,7 @@
 #undef _GNU_SOURCE
 #include <string.h>
 #include <stdio.h>
+#include <errno.h>
 #include "str_error.h"
 
 /* make sure libbpf doesn't use kernel-only integer typedefs */
@@ -15,7 +16,18 @@
 char *libbpf_strerror_r(int err, char *dst, int len)
 {
 	int ret = strerror_r(err < 0 ? -err : err, dst, len);
-	if (ret)
-		snprintf(dst, len, "ERROR: strerror_r(%d)=%d", err, ret);
+	/* on glibc <2.13, ret == -1 and errno is set, if strerror_r() can't
+	 * handle the error, on glibc >=2.13 *positive* (errno-like) error
+	 * code is returned directly
+	 */
+	if (ret == -1)
+		ret = errno;
+	if (ret) {
+		if (ret == EINVAL)
+			/* strerror_r() doesn't recognize this specific error */
+			snprintf(dst, len, "unknown error (%d)", err < 0 ? err : -err);
+		else
+			snprintf(dst, len, "ERROR: strerror_r(%d)=%d", err, ret);
+	}
 	return dst;
 }
diff --git a/src/usdt.bpf.h b/src/usdt.bpf.h
@@ -214,18 +214,18 @@ long bpf_usdt_cookie(struct pt_regs *ctx)
 
 /* we rely on ___bpf_apply() and ___bpf_narg() macros already defined in bpf_tracing.h */
 #define ___bpf_usdt_args0() ctx
-#define ___bpf_usdt_args1(x) ___bpf_usdt_args0(), ({ long _x; bpf_usdt_arg(ctx, 0, &_x); (void *)_x; })
-#define ___bpf_usdt_args2(x, args...) ___bpf_usdt_args1(args), ({ long _x; bpf_usdt_arg(ctx, 1, &_x); (void *)_x; })
-#define ___bpf_usdt_args3(x, args...) ___bpf_usdt_args2(args), ({ long _x; bpf_usdt_arg(ctx, 2, &_x); (void *)_x; })
-#define ___bpf_usdt_args4(x, args...) ___bpf_usdt_args3(args), ({ long _x; bpf_usdt_arg(ctx, 3, &_x); (void *)_x; })
-#define ___bpf_usdt_args5(x, args...) ___bpf_usdt_args4(args), ({ long _x; bpf_usdt_arg(ctx, 4, &_x); (void *)_x; })
-#define ___bpf_usdt_args6(x, args...) ___bpf_usdt_args5(args), ({ long _x; bpf_usdt_arg(ctx, 5, &_x); (void *)_x; })
-#define ___bpf_usdt_args7(x, args...) ___bpf_usdt_args6(args), ({ long _x; bpf_usdt_arg(ctx, 6, &_x); (void *)_x; })
-#define ___bpf_usdt_args8(x, args...) ___bpf_usdt_args7(args), ({ long _x; bpf_usdt_arg(ctx, 7, &_x); (void *)_x; })
-#define ___bpf_usdt_args9(x, args...) ___bpf_usdt_args8(args), ({ long _x; bpf_usdt_arg(ctx, 8, &_x); (void *)_x; })
-#define ___bpf_usdt_args10(x, args...) ___bpf_usdt_args9(args), ({ long _x; bpf_usdt_arg(ctx, 9, &_x); (void *)_x; })
-#define ___bpf_usdt_args11(x, args...) ___bpf_usdt_args10(args), ({ long _x; bpf_usdt_arg(ctx, 10, &_x); (void *)_x; })
-#define ___bpf_usdt_args12(x, args...) ___bpf_usdt_args11(args), ({ long _x; bpf_usdt_arg(ctx, 11, &_x); (void *)_x; })
+#define ___bpf_usdt_args1(x) ___bpf_usdt_args0(), ({ long _x; bpf_usdt_arg(ctx, 0, &_x); _x; })
+#define ___bpf_usdt_args2(x, args...) ___bpf_usdt_args1(args), ({ long _x; bpf_usdt_arg(ctx, 1, &_x); _x; })
+#define ___bpf_usdt_args3(x, args...) ___bpf_usdt_args2(args), ({ long _x; bpf_usdt_arg(ctx, 2, &_x); _x; })
+#define ___bpf_usdt_args4(x, args...) ___bpf_usdt_args3(args), ({ long _x; bpf_usdt_arg(ctx, 3, &_x); _x; })
+#define ___bpf_usdt_args5(x, args...) ___bpf_usdt_args4(args), ({ long _x; bpf_usdt_arg(ctx, 4, &_x); _x; })
+#define ___bpf_usdt_args6(x, args...) ___bpf_usdt_args5(args), ({ long _x; bpf_usdt_arg(ctx, 5, &_x); _x; })
+#define ___bpf_usdt_args7(x, args...) ___bpf_usdt_args6(args), ({ long _x; bpf_usdt_arg(ctx, 6, &_x); _x; })
+#define ___bpf_usdt_args8(x, args...) ___bpf_usdt_args7(args), ({ long _x; bpf_usdt_arg(ctx, 7, &_x); _x; })
+#define ___bpf_usdt_args9(x, args...) ___bpf_usdt_args8(args), ({ long _x; bpf_usdt_arg(ctx, 8, &_x); _x; })
+#define ___bpf_usdt_args10(x, args...) ___bpf_usdt_args9(args), ({ long _x; bpf_usdt_arg(ctx, 9, &_x); _x; })
+#define ___bpf_usdt_args11(x, args...) ___bpf_usdt_args10(args), ({ long _x; bpf_usdt_arg(ctx, 10, &_x); _x; })
+#define ___bpf_usdt_args12(x, args...) ___bpf_usdt_args11(args), ({ long _x; bpf_usdt_arg(ctx, 11, &_x); _x; })
 #define ___bpf_usdt_args(args...) ___bpf_apply(___bpf_usdt_args, ___bpf_narg(args))(args)
 
 /*

Original file line number	Diff line number	Diff line change
`@@ -1 +1 @@`
`1`		`-0737df6de94661ae55fd3343ce9abec32c687e62`
	`1`	`+009367099eb61a4fc2af44d4eb06b6b4de7de6db`
Original file line number	Diff line number	Diff line change
`@@ -301,7 +301,7 @@ int ring_buffer__consume_n(struct ring_buffer *rb, size_t n)`
`301`	`301`	`if (n == 0)`
`302`	`302`	`break;`
`303`	`303`	`}`
`304`		`- return res;`
	`304`	`+ return res > INT_MAX ? INT_MAX : res;`
`305`	`305`	`}`
`306`	`306`
`307`	`307`	`/* Consume available ring buffer(s) data without event polling.`
`@@ -405,7 +405,7 @@ int ring__map_fd(const struct ring *r)`
`405`	`405`
`406`	`406`	`int ring__consume_n(struct ring *r, size_t n)`
`407`	`407`	`{`
`408`		`- int res;`
	`408`	`+ int64_t res;`
`409`	`409`
`410`	`410`	`res = ringbuf_process_ring(r, n);`
`411`	`411`	`if (res < 0)`