You have been subscribed to a public bug:
== Comment: #0 - R. Wilson <wilso...@uk.ibm.com> - 2014-11-13 08:11:01 ==
---Problem Description---
system call msgrcv() from 32-bit application shows error: msgrcv: No message of
desired type
The following upstream commit resolves the issue.
commit e7ca2552369c1dfe0216c626baf82c3d83ec36bb
Author: Mateusz Guzik <mgu...@redhat.com>
Date: Mon Jan 27 17:07:11 2014 -0800
ipc: fix compat msgrcv with negative msgtyp
Compat function takes msgtyp argument as u32 and passes it down to
do_msgrcv which results in casting to long, thus the sign is lost and we
get a big positive number instead.
Cast the argument to signed type before passing it down.
We now hit the problem on Ubuntu 14_04 and need to know if a similar
patch is forthcoming.
---uname output---
Linux ctg-a-il-u1 3.13.0-39-generic #66-Ubuntu SMP Tue Oct 28 13:30:27 UTC 2014
x86_64 x86_64 x86_64 GNU/Linux
Machine Type = VMware guest
---Debugger---
A debugger is not configured
---Steps to Reproduce---
Compile test applications using gcc -m32 -o <name> <name.c>
Run test application testmsgs to send a message to a queue
Run test application testmsgr that *should* retriieve message sent by testmsgs
Observe that testmsgr does not retrieve message
Repeat test, compilling with -m64 instead - applications work as expected
Stack trace output:
no
Oops output:
no
Userspace tool common name: custom application designed to replicate problem
The userspace tool has the following bit modes: 32-bit
System Dump Info:
The system is not configured to capture a system dump.
== Comment: #2 - R. Wilson <wilso...@uk.ibm.com> - 2014-11-13 08:15:25 ==
Back trace for testmsgr:
(gdb) bt
#0 0xf777c430 in __kernel_vsyscall ()
#1 0xf76a4660 in msgrcv () from /lib32/libc.so.6
#2 0x08048573 in main ()
(gdb)
The msgrcv *should* have returned immediately as the message was placed
on the queue by testmsgs
** Affects: linux (Ubuntu)
Importance: Undecided
Status: New
** Tags: architecture-all bot-comment bugnameltc-118951 severity-critical
targetmilestone-inin---
--
Issue with msgrcv in a 32-bit application and -ve argument
https://bugs.launchpad.net/bugs/1393355
You received this bug notification because you are a member of Kernel Packages,
which is subscribed to linux in Ubuntu.
--
Mailing list: https://launchpad.net/~kernel-packages
Post to : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help : https://help.launchpad.net/ListHelp
