Public bug reported:

In last patch below

+From d65781527c8134a1202b2649695d48d5701ac60b Mon Sep 17 00:00:00 2001
+From: Christos Zoulas <chris...@zoulas.com>
+Date: Mon, 18 Feb 2019 17:46:56 +0000
+Subject: [PATCH] PR/62: spinpx: limit size of file_printable.

+===================================================================
+--- file-5.32.orig/src/readelf.c       2019-03-13 12:38:58.854781641 -0400
++++ file-5.32/src/readelf.c    2019-03-13 12:39:43.450945506 -0400
+@@ -725,7 +725,7 @@ do_core_note(struct magic_set *ms, unsig
+                       if (file_printf(ms, ", from '%.31s', pid=%u, uid=%u, "
+                           "gid=%u, nlwps=%u, lwp=%u (signal %u/code %u)",
+                           file_printable(sbuf, sizeof(sbuf),
+-                          CAST(char *, pi.cpi_name)),
++                          RCAST(char *, pi.cpi_name), sizeof(pi.cpi_name)),
+                           elf_getu32(swap, pi.cpi_pid),
+                           elf_getu32(swap, pi.cpi_euid),
+                           elf_getu32(swap, pi.cpi_egid),
+@@ -1564,7 +1564,8 @@ dophn_exec(struct magic_set *ms, int cla
+               return -1;
+       if (interp[0])
+               if (file_printf(ms, ", interpreter %s",
+-                  file_printable(ibuf, sizeof(ibuf), interp)) == -1)
++                  file_printable(ibuf, sizeof(ibuf), interp, sizeof(interp)))
++                      == -1)
+                       return -1;
+       return 0;
+ }

sizeof(interp) is passed to file_printable as the `slen' parameter, since 
interp is of 
type `char *', sizeof(interp) will be 8 or 4 const value for different pointer 
types, 
this makes the `interpreter' extraction for elf file limited to 8 bytes under 
x64. 

A example for this, under ubuntu 18.04:
$ file /bin/dash
/bin/dash: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically 
linked,
interpreter /lib64/l, for GNU/Linux 3.2.0, 
BuildID[sha1]=a783260e3a5fe0afdae77417eea7f
bf8d645219e, stripped

notice that the interpreter portion is `/lib64/l', which is 8 bytes long and 
only a part
of the actual interpreter path. 

the `slen' parameter here should be something like `sizeof(char) * 
length_of_buffer'
instead of sizeof(char *).

** Affects: file (Ubuntu)
     Importance: Undecided
         Status: New

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https://bugs.launchpad.net/bugs/1835596

Title:
  incorrect argument to file_printable in [PATCH] PR/62

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