print_array: enhance printing of unfetchable object addresses

When umoven_func invocation fails to fetch data, it prints the faulty
address.  If this happens to a subsequent umoven_func invocation,
the printed address may be undistinguishable from a valid data printed
by print_func, e.g. when the data is printed in a numeric form like
[0x1, 0x2, 0x3, 0xdefaced].

Fix this source of confusion by moving the printing of the faulty
address from umoven_func to print_array itself.  This change renames
umoven_func to tfetch_mem_func and changes its semantics, so that
 - tfetch_mem_func never prints anything;
 - tfetch_mem_func returns true if the fetch succeeded,
   and false otherwise.

* defs.h (print_array): Replace umoven_func argument with
tfetch_mem_func.
* util.c (print_array): Replace umoven_func argument with
tfetch_mem_func, document expected tfetch_mem_func return value
semantics.  When tfetch_mem_func returns false, print either addr
or "... /* addr */" depending on the context (inside the array or not).
* bpf.c (print_ebpf_prog, print_bpf_prog_info,
BEGIN_BPF_CMD_DECODER(BPF_PROG_QUERY)): Replace umoven_or_printaddr
argument of print_array with tfetch_mem.
* bpf_filter.c (print_bpf_fprog): Likewise.
* btrfs.c (btrfs_print_logical_ino_container,
btrfs_print_ino_path_container, btrfs_print_qgroup_inherit,
btrfs_ioctl): Likewise.
* dm.c (dm_decode_dm_target_deps): Likewise.
* epoll.c (epoll_wait_common): Likewise.
* file_ioctl.c (file_ioctl): Likewise.
* ipc_sem.c (tprint_sembuf_array): Likewise.
* kexec.c (print_kexec_segments): Likewise.
* mem.c (SYS_FUNC(subpage_prot)): Likewise.
* net.c (print_getsockopt): Likewise.
* netlink.c (decode_nlmsgerr_attr_cookie): Likewise.
* netlink_netlink_diag.c (decode_netlink_diag_groups): Likewise.
* netlink_packet_diag.c (decode_packet_diag_mclist): Likewise.
* netlink_unix_diag.c (decode_unix_diag_inode): Likewise.
* nlattr.c (decode_nla_meminfo): Likewise.
* numa.c (print_nodemask, SYS_FUNC(move_pages),
* perf_ioctl.c (perf_ioctl_query_bpf): Likewise.
* poll.c (decode_poll_entering): Likewise.
* printsiginfo.c (print_siginfo_array): Likewise.
* rtnl_tc.c (decode_tca_stab_data): Likewise.
* sock.c (decode_ifconf): Likewise.
* uid.c (print_groups): Likewise.
* io.c (SYS_FUNC(io_submit), SYS_FUNC(io_getevents)): Replace
umoven_or_printaddr argument of print_array with tfetch_mem.
(tprint_iov_upto): Replace umoven_or_printaddr_ignore_syserror
with tfetch_mem_ignore_syserror.
* v4l2.c (print_v4l2_format_fmt): Replace umoven_or_printaddr argument
of print_array with tfetch_mem.
(print_v4l2_ext_controls): Replace umoven_or_printaddr_ignore_syserror
with tfetch_mem_ignore_syserror.
* mmsghdr.c (fetch_struct_mmsghdr_or_printaddr): Rename
to fetch_struct_mmsghdr_for_print, do not print address, return bool.
(decode_mmsgvec): Replace fetch_struct_mmsghdr_or_printaddr
with fetch_struct_mmsghdr_for_print.
* tests/aio.c (main): Update expected output.
* tests/bpf.c (print_BPF_PROG_QUERY_attr5): Likewise.
* tests/ioctl_perf-success.c (main): Likewise.
* tests/ioctl_v4l2.c (main): Update expected output.
* tests/kexec_load.c (main): Likewise.
* tests/mmsg_name.c (test_mmsg_name): Update expected output.
* tests/move_pages.c (print_page_array, print_node_array): Likewise.
* tests/poll.c (print_pollfd_array_entering): Likewise.
* tests/preadv-pwritev.c (main): Likewise.
* tests/preadv2-pwritev2.c (dumpio): Likewise.
* tests/process_vm_readv_writev.c (print_iov): Likewise.
* tests/pwritev.c (print_iovec): Likewise.
* tests/readv.c (main): Likewise.
* tests/seccomp-filter-v.c
* tests/semop.c (main): Likewise.
* tests/set_mempolicy.c (print_nodes): Likewise.
* tests/setgroups.c (main): Likewise.
* tests/test_nlattr.h (print_nlattr) Likewise.

Co-Authored-by: Eugene Syromyatnikov <evgsyr@gmail.com>

aio.c

@@ -196,7 +196,7 @@ SYS_FUNC(io_submit)
 		printaddr(addr);
 	else
 		print_array(tcp, addr, nr, &iocbp, current_wordsize,
-			    umoven_or_printaddr, print_iocbp, 0);
+			    tfetch_mem, print_iocbp, 0);
 
 	return RVAL_DECODED;
 }
@@ -248,7 +248,7 @@ SYS_FUNC(io_getevents)
 	} else {
 		struct io_event buf;
 		print_array(tcp, tcp->u_arg[3], tcp->u_rval, &buf, sizeof(buf),
-			    umoven_or_printaddr, print_io_event, 0);
+			    tfetch_mem, print_io_event, 0);
 		tprints(", ");
 		/*
 		 * Since the timeout parameter is read by the kernel

bpf.c

@@ -172,7 +172,7 @@ print_ebpf_prog(struct tcb *const tcp, const kernel_ulong_t addr,
 		struct ebpf_insn insn;
 
 		print_array(tcp, addr, len, &insn, sizeof(insn),
-			    umoven_or_printaddr, print_ebpf_insn, &eid);
+			    tfetch_mem, print_ebpf_insn, &eid);
 	}
 }
 
@@ -519,7 +519,7 @@ print_bpf_prog_info(struct tcb * const tcp, uint32_t bpf_fd,
 	print_big_u64_addr(info.map_ids);
 	print_array(tcp, info.map_ids, info.nr_map_ids,
 		    &map_id_buf, sizeof(map_id_buf),
-		    umoven_or_printaddr, print_uint64_array_member, 0);
+		    tfetch_mem, print_uint64_array_member, 0);
 
 	PRINT_FIELD_IFINDEX(", ", info, ifindex);
 	PRINT_FIELD_DEV(", ", info, netns_dev);
@@ -637,7 +637,7 @@ BEGIN_BPF_CMD_DECODER(BPF_PROG_QUERY)
 
 	print_big_u64_addr(attr.prog_ids);
 	print_array(tcp, attr.prog_ids, attr.prog_cnt, &prog_id_buf,
-		    sizeof(prog_id_buf), umoven_or_printaddr,
+		    sizeof(prog_id_buf), tfetch_mem,
 		    print_uint32_array_member, 0);
 
 	tprints(", prog_cnt=");

bpf_filter.c

@@ -183,7 +183,7 @@ print_bpf_fprog(struct tcb *const tcp, const kernel_ulong_t addr,
 		struct bpf_filter_block filter;
 
 		print_array(tcp, addr, len, &filter, sizeof(filter),
-			    umoven_or_printaddr, print_bpf_filter_block, &fbd);
+			    tfetch_mem, print_bpf_filter_block, &fbd);
 	}
 }
 

btrfs.c

@@ -301,7 +301,7 @@ btrfs_print_logical_ino_container(struct tcb *tcp,
 		tprints(", val=");
 		print_array(tcp, val_addr, container.elem_cnt / 3,
 			    record, sizeof(record),
-			    umoven_or_printaddr,
+			    tfetch_mem,
 			    print_btrfs_data_container_logical_ino, 0);
 	}
 
@@ -340,7 +340,7 @@ btrfs_print_ino_path_container(struct tcb *tcp,
 		tprints(", val=");
 		print_array(tcp, val_addr, container.elem_cnt,
 			    &offset, sizeof(offset),
-			    umoven_or_printaddr,
+			    tfetch_mem,
 			    print_btrfs_data_container_ino_path, &val_addr);
 	}
 
@@ -370,7 +370,7 @@ btrfs_print_qgroup_inherit(struct tcb *const tcp, const kernel_ulong_t qgi_addr)
 		tprints(", qgroups=");
 		print_array(tcp, qgi_addr + offsetof(typeof(inherit), qgroups),
 			    inherit.num_qgroups, &record, sizeof(record),
-			    umoven_or_printaddr, print_uint64_array_member, 0);
+			    tfetch_mem, print_uint64_array_member, 0);
 	}
 	tprints("}");
 }
@@ -1158,7 +1158,7 @@ MPERS_PRINTER_DECL(int, btrfs_ioctl,
 			print_array(tcp, ptr_to_kulong(args.clone_sources),
 				    args.clone_sources_count,
 				    &record, sizeof(record),
-				    umoven_or_printaddr,
+				    tfetch_mem,
 				    print_objectid_callback, 0);
 		}
 		btrfs_print_objectid(", ", args, parent_root);
@@ -1201,7 +1201,7 @@ MPERS_PRINTER_DECL(int, btrfs_ioctl,
 			tprints(", spaces=");
 			print_array(tcp, arg + offsetof(typeof(args), spaces),
 				    args.total_spaces,
-				    &info, sizeof(info), umoven_or_printaddr,
+				    &info, sizeof(info), tfetch_mem,
 				    print_btrfs_ioctl_space_info, 0);
 		}
 		tprints("}");

defs.h

@@ -794,14 +794,14 @@ print_array(struct tcb *,
 	    size_t nmemb,
 	    void *elem_buf,
 	    size_t elem_size,
-	    int (*umoven_func)(struct tcb *,
-				     kernel_ulong_t,
-				     unsigned int,
-				     void *),
+	    bool (*tfetch_mem_func)(struct tcb *,
+				    kernel_ulong_t addr,
+				    unsigned int len,
+				    void *laddr),
 	    bool (*print_func)(struct tcb *,
-				     void *elem_buf,
-				     size_t elem_size,
-				     void *opaque_data),
+			       void *elem_buf,
+			       size_t elem_size,
+			       void *opaque_data),
 	    void *opaque_data);
 
 extern kernel_ulong_t *

dm.c

@@ -237,7 +237,7 @@ dm_decode_dm_target_deps(struct tcb *const tcp, const kernel_ulong_t addr,
 
 	tprints(", deps=");
 	print_array(tcp, addr + offset_end, s.count, &dev_buf, sizeof(dev_buf),
-		    umoven_or_printaddr, dm_print_dev, NULL);
+		    tfetch_mem, dm_print_dev, NULL);
 
 	tprints("}");
 

epoll.c

@@ -94,7 +94,7 @@ epoll_wait_common(struct tcb *tcp)
 	} else {
 		struct epoll_event ev;
 		print_array(tcp, tcp->u_arg[1], tcp->u_rval, &ev, sizeof(ev),
-			    umoven_or_printaddr, print_epoll_event, 0);
+			    tfetch_mem, print_epoll_event, 0);
 		tprintf(", %d, %d", (int) tcp->u_arg[2], (int) tcp->u_arg[3]);
 	}
 }

file_ioctl.c

@@ -185,7 +185,7 @@ file_ioctl(struct tcb *const tcp, const unsigned int code,
 
 		rc = print_array(tcp, arg + offsetof(typeof(args), info),
 				 args.dest_count, &info, sizeof(info),
-				 umoven_or_printaddr,
+				 tfetch_mem,
 				 print_file_dedupe_range_info, limit);
 
 		tprints("}");
@@ -233,7 +233,7 @@ file_ioctl(struct tcb *const tcp, const unsigned int code,
 			print_array(tcp,
 				    arg + offsetof(typeof(args), fm_extents),
 				    args.fm_mapped_extents, &fe, sizeof(fe),
-				    umoven_or_printaddr,
+				    tfetch_mem,
 				    print_fiemap_extent, 0);
 		}
 		tprints("}");

io.c

@@ -123,7 +123,7 @@ tprint_iov_upto(struct tcb *const tcp, const kernel_ulong_t len,
 	};
 
 	print_array(tcp, addr, len, iov, current_wordsize * 2,
-		    umoven_or_printaddr_ignore_syserror, print_iovec, &config);
+		    tfetch_mem_ignore_syserror, print_iovec, &config);
 }
 
 SYS_FUNC(readv)

ipc_sem.c

@@ -64,7 +64,7 @@ tprint_sembuf_array(struct tcb *const tcp, const kernel_ulong_t addr,
 #if defined HAVE_SYS_SEM_H || defined HAVE_LINUX_SEM_H
 	struct sembuf sb;
 	print_array(tcp, addr, count, &sb, sizeof(sb),
-		    umoven_or_printaddr, print_sembuf, 0);
+		    tfetch_mem, print_sembuf, 0);
 #else
 	printaddr(addr);
 #endif

kexec.c

@@ -76,7 +76,7 @@ print_kexec_segments(struct tcb *const tcp, const kernel_ulong_t addr,
 	const size_t sizeof_seg = ARRAY_SIZE(seg) * current_wordsize;
 
 	print_array(tcp, addr, len, seg, sizeof_seg,
-		    umoven_or_printaddr, print_seg, 0);
+		    tfetch_mem, print_seg, 0);
 }
 
 SYS_FUNC(kexec_load)

mem.c

@@ -360,7 +360,7 @@ SYS_FUNC(subpage_prot)
 
 	unsigned int entry;
 	print_array(tcp, map, nmemb, &entry, sizeof(entry),
-		    umoven_or_printaddr, print_protmap_entry, 0);
+		    tfetch_mem, print_protmap_entry, 0);
 
 	return RVAL_DECODED;
 }

mmsghdr.c

@@ -34,18 +34,13 @@
 #include "xstring.h"
 #include <limits.h>
 
-static int
-fetch_struct_mmsghdr_or_printaddr(struct tcb *const tcp,
+static bool
+fetch_struct_mmsghdr_for_print(struct tcb *const tcp,
 				  const kernel_ulong_t addr,
 				  const unsigned int len, void *const mh)
 {
-	if ((entering(tcp) || !syserror(tcp))
-	    && fetch_struct_mmsghdr(tcp, addr, mh)) {
-		return 0;
-	} else {
-		printaddr(addr);
-		return -1;
-	}
+	return (entering(tcp) || !syserror(tcp)) &&
+	       fetch_struct_mmsghdr(tcp, addr, mh);
 }
 
 struct print_struct_mmsghdr_config {
@@ -146,7 +141,7 @@ decode_mmsgvec(struct tcb *const tcp, const kernel_ulong_t addr,
 	}
 
 	print_array(tcp, addr, vlen, &mmsg, sizeof_struct_mmsghdr(),
-		    fetch_struct_mmsghdr_or_printaddr,
+		    fetch_struct_mmsghdr_for_print,
 		    print_struct_mmsghdr, &c);
 }
 

net.c

@@ -739,7 +739,7 @@ print_getsockopt(struct tcb *const tcp, const unsigned int level,
 			uint32_t buf;
 			print_array(tcp, addr, MIN(ulen, rlen) / sizeof(buf),
 				    &buf, sizeof(buf),
-				    umoven_or_printaddr, print_uint32, 0);
+				    tfetch_mem, print_uint32, 0);
 			break;
 			}
 		default:

netlink.c

@@ -473,7 +473,7 @@ decode_nlmsgerr_attr_cookie(struct tcb *const tcp,
 	const size_t nmemb = len / sizeof(cookie);
 
 	print_array(tcp, addr, nmemb, &cookie, sizeof(cookie),
-		    umoven_or_printaddr, print_cookie, 0);
+		    tfetch_mem, print_cookie, 0);
 
 	return true;
 }

netlink_netlink_diag.c

@@ -98,7 +98,7 @@ decode_netlink_diag_groups(struct tcb *const tcp,
 		return false;
 
 	print_array(tcp, addr, nmemb, &buf, current_wordsize,
-		    umoven_or_printaddr, print_group, 0);
+		    tfetch_mem, print_group, 0);
 
 	return true;
 }

netlink_packet_diag.c

@@ -121,7 +121,7 @@ decode_packet_diag_mclist(struct tcb *const tcp,
 		return false;
 
 	print_array(tcp, addr, nmemb, &dml, sizeof(dml),
-		    umoven_or_printaddr, print_packet_diag_mclist, 0);
+		    tfetch_mem, print_packet_diag_mclist, 0);
 
 	return true;
 }

netlink_unix_diag.c

@@ -107,7 +107,7 @@ decode_unix_diag_inode(struct tcb *const tcp,
 		return false;
 
 	print_array(tcp, addr, nmemb, &inode, sizeof(inode),
-		    umoven_or_printaddr, print_inode, 0);
+		    tfetch_mem, print_inode, 0);
 
 	return true;
 }

nlattr.c

@@ -192,7 +192,7 @@ decode_nla_meminfo(struct tcb *const tcp,
 
 	unsigned int count = 0;
 	print_array(tcp, addr, nmemb, &mem, sizeof(mem),
-		    umoven_or_printaddr, print_uint32_array_member, &count);
+		    tfetch_mem, print_uint32_array_member, &count);
 
 	return true;
 }

numa.c

@@ -59,7 +59,7 @@ print_nodemask(struct tcb *const tcp, const kernel_ulong_t addr,
 
 	kernel_ulong_t buf;
 	print_array(tcp, addr, nmemb, &buf, current_wordsize,
-		    umoven_or_printaddr, print_node, 0);
+		    tfetch_mem, print_node, 0);
 }
 
 SYS_FUNC(migrate_pages)
@@ -166,14 +166,14 @@ SYS_FUNC(move_pages)
 	if (entering(tcp)) {
 		tprintf("%d, %" PRI_klu ", ", (int) tcp->u_arg[0], npages);
 		print_array(tcp, tcp->u_arg[2], npages, &buf, current_wordsize,
-			    umoven_or_printaddr, print_addr, 0);
+			    tfetch_mem, print_addr, 0);
 		tprints(", ");
 		print_array(tcp, tcp->u_arg[3], npages, &buf, sizeof(int),
-			    umoven_or_printaddr, print_int, 0);
+			    tfetch_mem, print_int, 0);
 		tprints(", ");
 	} else {
 		print_array(tcp, tcp->u_arg[4], npages, &buf, sizeof(int),
-			    umoven_or_printaddr, print_status, 0);
+			    tfetch_mem, print_status, 0);
 		tprints(", ");
 		printflags(move_pages_flags, tcp->u_arg[5], "MPOL_???");
 	}

perf_ioctl.c

@@ -67,7 +67,7 @@ perf_ioctl_query_bpf(struct tcb *const tcp, const kernel_ulong_t arg)
 
 	print_array(tcp, arg + offsetof(struct perf_event_query_bpf, ids), info,
 		    &info, sizeof(info),
-		    umoven_or_printaddr, print_uint32_array_member, NULL);
+		    tfetch_mem, print_uint32_array_member, NULL);
 
 	tprints("}");
 

poll.c

@@ -57,7 +57,7 @@ decode_poll_entering(struct tcb *tcp)
 	struct pollfd fds;
 
 	print_array(tcp, addr, nfds, &fds, sizeof(fds),
-		    umoven_or_printaddr, print_pollfd, 0);
+		    tfetch_mem, print_pollfd, 0);
 	tprintf(", %u, ", nfds);
 }
 

printsiginfo.c

@@ -277,5 +277,5 @@ MPERS_PRINTER_DECL(void, print_siginfo_array, struct tcb *const tcp,
 	siginfo_t si;
 
 	print_array(tcp, addr, len, &si, sizeof(si),
-		    umoven_or_printaddr, print_siginfo_t, 0);
+		    tfetch_mem, print_siginfo_t, 0);
 }

rtnl_tc.c

@@ -259,7 +259,7 @@ decode_tca_stab_data(struct tcb *const tcp,
 		return false;
 
 	print_array(tcp, addr, nmemb, &data, sizeof(data),
-		    umoven_or_printaddr, print_stab_data, NULL);
+		    tfetch_mem, print_stab_data, NULL);
 
 	return true;
 }

sock.c

@@ -310,7 +310,7 @@ decode_ifconf(struct tcb *const tcp, const kernel_ulong_t addr)
 		print_array(tcp, ptr_to_kulong(ifc->ifc_buf),
 			    ifc->ifc_len / sizeof(struct_ifreq),
 			    &ifr, sizeof(ifr),
-			    umoven_or_printaddr, print_ifconf_ifreq, NULL);
+			    tfetch_mem, print_ifconf_ifreq, NULL);
 	}
 
 	tprints("}");

tests/aio.c

@@ -335,7 +335,7 @@ main(void)
 	       "}, {aio_key=%u, aio_lio_opcode=IOCB_CMD_PWRITEV"
 		", aio_reqprio=%hd, aio_fildes=%d, aio_buf=%#" PRI__x64
 		", aio_nbytes=%" PRI__u64 ", aio_offset=%" PRI__d64
-	       "}, {NULL}, {%#lx}, %p]) = %s\n",
+	       "}, {NULL}, {%#lx}, ... /* %p */]) = %s\n",
 	       *ctx, 1057L,
 	       cbv2[0].aio_data, cbv2[0].aio_key,
 	       cbv2[0].aio_lio_opcode, cbv2[0].aio_fildes,

tests/bpf.c

@@ -918,7 +918,8 @@ print_BPF_PROG_QUERY_attr5(const struct bpf_attr_check *check, unsigned long add
 	       ", query_flags=BPF_F_QUERY_EFFECTIVE|0xdeadf00c"
 	       ", attach_flags=BPF_F_ALLOW_MULTI|0xbeefcafc"
 #if defined(INJECT_RETVAL) && INJECT_RETVAL > 0
-	       ", prog_ids=[0, 1, 4294967295, 2718281828, %p], prog_cnt=5}",
+	       ", prog_ids=[0, 1, 4294967295, 2718281828, ... /* %p */]"
+	       ", prog_cnt=5}",
 	       prog_load_ids_ptr + ARRAY_SIZE(prog_load_ids)
 #else
 	       ", prog_ids=%p, prog_cnt=5}", prog_load_ids_ptr

tests/ioctl_perf-success.c

@@ -143,7 +143,7 @@ main(int argc, char **argv)
 	u32_arr[1] = 5;
 	assert(ioctl(-1, PERF_EVENT_IOC_QUERY_BPF, u32_arr) == inject_retval);
 	printf("ioctl(-1, PERF_EVENT_IOC_QUERY_BPF, {ids_len=3134983661"
-	       ", prog_cnt=5, ids=[3737845741, 3735928559, %p]})"
+	       ", prog_cnt=5, ids=[3737845741, 3735928559, ... /* %p */]})"
 	       " = %ld (INJECTED)\n",
 	       u32_efault, inject_retval);
 

tests/ioctl_v4l2.c

@@ -898,7 +898,7 @@ main(void)
 	       ", {ctrl_class=V4L2_CTRL_CLASS_MPEG, count=%u, controls="
 	       "[{id=V4L2_CID_BRIGHTNESS, size=0, value=%d, value64=%lld}"
 	       ", {id=V4L2_CID_CONTRAST, size=2, string=\"\\377\\377\"}"
-	       ", %p]}) = -1 EBADF (%m)\n",
+	       ", ... /* %p */]}) = -1 EBADF (%m)\n",
 	       p_ext_controls->count,
 	       p_ext_controls->controls[0].value,
 	       (long long) p_ext_controls->controls[0].value64,

tests/kexec_load.c

@@ -129,7 +129,7 @@ main(void)
 		printf("{buf=%p, bufsz=%zu, mem=%p, memsz=%zu}, ",
 		       segms[i].buf, segms[i].bufsz,
 		       segms[i].mem, segms[i].memsz);
-	printf("%p], %s%s) = %s\n",
+	printf("... /* %p */], %s%s) = %s\n",
 	       segms + NUM_SEGMS,
 	       sizeof(long) == 8 ? flags[0].str64 : flags[0].str32,
 	       flags[0].str, errstr);

tests/mmsg_name.c

@@ -152,7 +152,7 @@ test_mmsg_name(const int send_fd, const int recv_fd)
 	printf("sendmmsg(-1, [{msg_hdr=");
 	print_msghdr(&send_mh[IOV_MAX].msg_hdr, 0);
 	errno = saved_errno;
-	printf("}, %p], %u, MSG_DONTWAIT) = %d %s (%m)\n",
+	printf("}, ... /* %p */], %u, MSG_DONTWAIT) = %d %s (%m)\n",
 	       &send_mh[IOV_MAX1], 2, rc, errno2name());
 
 	rc = send_mmsg(send_fd, send_mh, IOV_MAX1, MSG_DONTWAIT);

tests/move_pages.c

@@ -63,7 +63,7 @@ print_page_array(const void **const pages,
 				break;
 			}
 		} else {
-			printf("%p", pages + i);
+			printf("... /* %p */", pages + i);
 			break;
 		}
 		const void *const addr = pages[i];
@@ -99,7 +99,7 @@ print_node_array(const int *const nodes,
 				break;
 			}
 		} else {
-			printf("%p", nodes + i);
+			printf("... /* %p */", nodes + i);
 			break;
 		}
 		printf("%d", nodes[i]);

tests/poll.c

@@ -95,7 +95,7 @@ print_pollfd_array_entering(const struct pollfd *const pfd,
 		if (i)
 			tprintf(", ");
 		if (i >= valid) {
-			tprintf("%p", &pfd[i]);
+			tprintf("... /* %p */", &pfd[i]);
 			break;
 		}
 		if (i >= abbrev) {

tests/preadv-pwritev.c

@@ -99,7 +99,7 @@ main(void)
 	tprintf("pwritev(1, [], 0, 0) = 0\n");
 
 	rc = pwritev(1, w_iov + ARRAY_SIZE(w_iov_) - 1, 2, 0);
-	tprintf("pwritev(1, [{iov_base=\"%s\", iov_len=%u}, %p], 2, 0)"
+	tprintf("pwritev(1, [{iov_base=\"%s\", iov_len=%u}, ... /* %p */], 2, 0)"
 		" = %ld %s (%m)\n",
 		w2_c, LENGTH_OF(w2_c), w_iov + ARRAY_SIZE(w_iov_),
 		rc, errno2name());

tests/preadv2-pwritev2.c

@@ -104,7 +104,7 @@ dumpio(void)
 	tprintf("pwritev2(1, [], 0, 0, 0) = 0\n");
 
 	rc = pw(1, w_iov + ARRAY_SIZE(w_iov_) - 1, 2, 0);
-	tprintf("pwritev2(1, [{iov_base=\"%s\", iov_len=%u}, %p], 2, 0, 0)"
+	tprintf("pwritev2(1, [{iov_base=\"%s\", iov_len=%u}, ... /* %p */], 2, 0, 0)"
 		" = %ld %s (%m)\n",
 		w2_c, LENGTH_OF(w2_c), w_iov + ARRAY_SIZE(w_iov_),
 		rc, errno2name());

tests/process_vm_readv_writev.c

@@ -135,7 +135,7 @@ print_iov(const struct iovec *iov, const void *arg_ptr, long rc)
 	}
 
 	if (arg->addr_term)
-		printf(", %p", iov + arg->count);
+		printf(", ... /* %p */", iov + arg->count);
 
 	printf("]");
 }

tests/pwritev.c

@@ -65,7 +65,7 @@ print_iovec(const struct iovec *iov, unsigned int cnt, unsigned int size)
 		if (i)
 			fputs(", ", stdout);
 		if (i == size) {
-			printf("%p", &iov[i]);
+			printf("... /* %p */", &iov[i]);
 			break;
 		}
 		if (i == LIM) {

tests/readv.c

@@ -89,7 +89,7 @@ main(void)
 		fds[1], (long) writev(fds[1], w_iov, 0));
 
 	rc = writev(fds[1], w_iov + ARRAY_SIZE(w_iov_) - 1, 2);
-	tprintf("writev(%d, [{iov_base=\"%s\", iov_len=%u}, %p], 2)"
+	tprintf("writev(%d, [{iov_base=\"%s\", iov_len=%u}, ... /* %p */], 2)"
 		" = %ld %s (%m)\n",
 		fds[1], w2_c, LENGTH_OF(w2_c), w_iov + ARRAY_SIZE(w_iov_),
 		rc, errno2name());

tests/seccomp-filter-v.c

@@ -118,7 +118,7 @@ main(void)
 	prog->len = 3;
 	syscall(__NR_seccomp, SECCOMP_SET_MODE_FILTER, 0, prog);
 	tprintf("seccomp(SECCOMP_SET_MODE_FILTER, 0, {len=%u"
-		", filter=[%s, %p]}) = -1 EFAULT (%m)\n",
+		", filter=[%s, ... /* %p */]}) = -1 EFAULT (%m)\n",
 		prog->len, kill_stmt_txt, filter +  ARRAY_SIZE(filter_c));
 
 	prog->len = 0;

tests/semop.c

@@ -64,7 +64,7 @@ main(void)
 	sem_b2->sem_flg = 0xbeef;
 
 	rc = semop(bogus_semid, sem_b2, 2);
-	printf("semop(%d, [{%hu, %hd, %s%s%#hx}, %p], %u) = %s\n",
+	printf("semop(%d, [{%hu, %hd, %s%s%#hx}, ... /* %p */], %u) = %s\n",
 		bogus_semid, sem_b2->sem_num, sem_b2->sem_op,
 		sem_b2->sem_flg & SEM_UNDO ? "SEM_UNDO|" : "",
 		sem_b2->sem_flg & IPC_NOWAIT ? "IPC_NOWAIT|" : "",
@@ -91,7 +91,7 @@ main(void)
 	ts->tv_sec = 1;
 	ts->tv_nsec = 123456789;
 	rc = semtimedop(bogus_semid, sem_b2, 2, ts);
-	printf("semtimedop(%d, [{%hu, %hd, %s%s%#hx}, %p], %u"
+	printf("semtimedop(%d, [{%hu, %hd, %s%s%#hx}, ... /* %p */], %u"
 		", {tv_sec=%lld, tv_nsec=%llu}) = %s\n",
 		bogus_semid, sem_b2->sem_num, sem_b2->sem_op,
 		sem_b2->sem_flg & SEM_UNDO ? "SEM_UNDO|" : "",

tests/set_mempolicy.c

@@ -76,7 +76,7 @@ print_nodes(const unsigned long maxnode, unsigned int offset)
 				printf("%#0*lx", (int) sizeof(long) * 2 + 2,
 				       nodemask[i]);
 			} else {
-				printf("%p", nodemask + i);
+				printf("... /* %p */", nodemask + i);
 				break;
 			}
 		}

tests/setgroups.c

@@ -115,7 +115,7 @@ main(void)
 	errstr = sprintrc(rc);
 	printf("%s(2, [", SYSCALL_NAME);
 	printuid(*g1);
-	printf(", %p]) = %s\n", g1 + 1, errstr);
+	printf(", ... /* %p */]) = %s\n", g1 + 1, errstr);
 
 	g2[0] = -2;
 	g2[1] = -3;
@@ -133,7 +133,7 @@ main(void)
 	printuid(g2[0]);
 	printf(", ");
 	printuid(g2[1]);
-	printf(", %p]) = %s\n", g2 + 2, errstr);
+	printf(", ... /* %p */]) = %s\n", g2 + 2, errstr);
 
 	g3[0] = 0;
 	g3[1] = 1;

tests/test_nlattr.h

@@ -186,7 +186,7 @@ print_nlattr(const unsigned int nla_len, const char *const nla_type)
 				if (i) printf(", ");			\
 				(print_elem_)(&(obj_)[i], i);		\
 			}						\
-			printf(", %p]",					\
+			printf(", ... /* %p */]",			\
 			       RTA_DATA(NLMSG_ATTR(nlh, (hdrlen_)))	\
 			        + sizeof(obj_) - sizeof((obj_)[0])));	\
 		/* sizeof(obj_) */					\
@@ -308,7 +308,7 @@ print_nlattr(const unsigned int nla_len, const char *const nla_type)
 				if (i) printf(", ");			\
 				(print_elem_)(&(obj_)[i]);		\
 			}						\
-			printf(", %p]}",				\
+			printf(", ... /* %p */]}",			\
 			       RTA_DATA(TEST_NLATTR_nla)		\
 			        + sizeof((obj_)[0])));			\
 		/* sizeof(obj_) */					\

uid.c

@@ -180,7 +180,7 @@ print_groups(struct tcb *const tcp, const unsigned int len,
 
 	uid_t gid;
 	print_array(tcp, addr, len, &gid, sizeof(gid),
-		    umoven_or_printaddr, print_gid, 0);
+		    tfetch_mem, print_gid, 0);
 }
 
 SYS_FUNC(setgroups)

util.c

@@ -1060,8 +1060,8 @@ print_uint64_array_member(struct tcb *tcp, void *elem_buf, size_t elem_size,
  *
  * Array elements are being fetched to the address specified by elem_buf.
  *
- * The fetcher callback function specified by umoven_func should follow
- * the same semantics as umoven_or_printaddr function.
+ * The fetcher callback function specified by tfetch_mem_func should follow
+ * the same semantics as tfetch_mem function.
  *
  * The printer callback function specified by print_func is expected
  * to print something; if it returns false, no more iterations will be made.
@@ -1073,9 +1073,7 @@ print_uint64_array_member(struct tcb *tcp, void *elem_buf, size_t elem_size,
  * - "NULL", if start_addr is NULL;
  * - "[]", if nmemb is 0;
  * - start_addr, if nmemb * elem_size overflows or wraps around;
- * - nothing, if the first element cannot be fetched
- *   (if umoven_func returns non-zero), but it is assumed that
- *   umoven_func has printed the address it failed to fetch data from;
+ * - start_addr, if the first tfetch_mem_func invocation returned false;
  * - elements of the array, delimited by ", ", with the array itself
  *   enclosed with [] brackets.
  *
@@ -1084,9 +1082,8 @@ print_uint64_array_member(struct tcb *tcp, void *elem_buf, size_t elem_size,
  * - "..." is printed instead of max_strlen+1 element
  *   and no more iterations will be made.
  *
- * This function returns true only if
- * - umoven_func has been called at least once AND
- * - umoven_func has not returned false.
+ * This function returns true only if tfetch_mem_func has returned true
+ * at least once.
  */
 bool
 print_array(struct tcb *const tcp,
@@ -1094,10 +1091,10 @@ print_array(struct tcb *const tcp,
 	    const size_t nmemb,
 	    void *const elem_buf,
 	    const size_t elem_size,
-	    int (*const umoven_func)(struct tcb *,
-				     kernel_ulong_t,
-				     unsigned int,
-				     void *),
+	    bool (*const tfetch_mem_func)(struct tcb *,
+					  kernel_ulong_t addr,
+					  unsigned int len,
+					  void *laddr),
 	    bool (*const print_func)(struct tcb *,
 				     void *elem_buf,
 				     size_t elem_size,
@@ -1131,8 +1128,15 @@ print_array(struct tcb *const tcp,
 		if (cur != start_addr)
 			tprints(", ");
 
-		if (umoven_func(tcp, cur, elem_size, elem_buf))
+		if (!tfetch_mem_func(tcp, cur, elem_size, elem_buf)) {
+			if (cur == start_addr)
+				printaddr(cur);
+			else {
+				tprints("...");
+				printaddr_comment(cur);
+			}
 			break;
+		}
 
 		if (cur == start_addr)
 			tprints("[");

v4l2.c

@@ -270,7 +270,7 @@ print_v4l2_format_fmt(struct tcb *const tcp, const char *prefix,
 		tprintf(", chromakey=%#x, clips=", f->fmt.win.chromakey);
 		ret = print_array(tcp, ptr_to_kulong(f->fmt.win.clips),
 				  f->fmt.win.clipcount, &clip, sizeof(clip),
-				  umoven_or_printaddr, print_v4l2_clip, 0);
+				  tfetch_mem, print_v4l2_clip, 0);
 		tprintf(", clipcount=%u, bitmap=", f->fmt.win.clipcount);
 		printaddr(ptr_to_kulong(f->fmt.win.bitmap));
 #ifdef HAVE_STRUCT_V4L2_WINDOW_GLOBAL_ALPHA
@@ -853,7 +853,7 @@ print_v4l2_ext_controls(struct tcb *const tcp, const kernel_ulong_t arg,
 	struct_v4l2_ext_control ctrl;
 	bool fail = !print_array(tcp, ptr_to_kulong(c.controls), c.count,
 				 &ctrl, sizeof(ctrl),
-				 umoven_or_printaddr_ignore_syserror,
+				 tfetch_mem_ignore_syserror,
 				 print_v4l2_ext_control, 0);
 
 	if (exiting(tcp) && syserror(tcp))