Project

General

Profile

Actions

Bug #13866

closed

libipadm ipadm_addr_info not 64bit safe

Added by Hans Rosenfeld 6 months ago. Updated 4 months ago.

Status:
Closed
Priority:
Normal
Category:
lib - userland libraries
Start date:
Due date:
% Done:

100%

Estimated time:
Difficulty:
Medium
Tags:
Gerrit CR:

Description

Using a 64bit libipadm (#13863) breaks ipadm_addr_info().

libipadm uses a door to get the address information from ipmgmtd, which is a 32bit process. The data passed through the door is a ipmgmt_get_rval_t followed by a packed nvlist. The definition of ipmgmt_get_rval_t in ipadm_ipmgmt.h is as follows:

typedef struct ipmgmt_get_rval_s {
    int32_t        ir_err;
    size_t    ir_nvlsize;
    /* packed nvl follows */
} ipmgmt_get_rval_t;

Obviously size_t is 4 bytes in a 32bit process and 8 bytes in a 64bit process. Additionally, 64bit compiler will usually add 4 bytes of padding between ir_err and ir_nvlsize to align the latter to a 64bit boundary. Hence the 64bit libipadm will misinterpret what the 32bit ipmgmtd is sending, confusing nvlist_unpack() which is subsequently called. It works the other way around, but only by accident.

This can be fixed easily by changing the definition like this:

typedef struct ipmgmt_get_rval_s {
    int64_t        ir_err;
    uint64_t    ir_nvlsize;
    /* packed nvl follows */
} ipmgmt_get_rval_t;

Testing: I rebuilt both 32bit and 64bit libipadm and a 32bit ipmgmtd with this change. The problem observed previously disappeared.

Actions #1

Updated by Electric Monk 6 months ago

  • Gerrit CR set to 1540
Actions #2

Updated by Hans Rosenfeld 4 months ago

Additional testing: I've verified that the ipadm commands show-addr and create-addr still work as expected in non-global zones as well as the global zone.

Actions #3

Updated by Electric Monk 4 months ago

  • Status changed from In Progress to Closed
  • % Done changed from 0 to 100

git commit 0a8fc1cbac5c0b540cc1948761e1ea321879e522

commit  0a8fc1cbac5c0b540cc1948761e1ea321879e522
Author: Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
Date:   2021-07-22T15:08:04.000Z

    13866 libipadm ipadm_addr_info not 64bit safe
    Reviewed by: Robert Mustacchi <rm+illumos@fingolfin.org>
    Reviewed by: Andy Fiddaman <andy@omnios.org>
    Reviewed by: Toomas Soome <tsoome@me.com>
    Approved by: Dan McDonald <danmcd@joyent.com>

Actions

Also available in: Atom PDF