Bug 2218620

Summary:	glibc: segmentation fault with char array of large sizes
Product:	Red Hat Enterprise Linux 8	Reporter:	Tim Zielke <tim.zielke>
Component:	glibc	Assignee:	glibc team <glibc-bugzilla>
Status:	CLOSED NOTABUG	QA Contact:	qe-baseos-tools-bugs
Severity:	low	Docs Contact:
Priority:	unspecified
Version:	8.8	CC:	ashankar, codonell, cww, dj, fweimer, pfrankli, sipoyare
Target Milestone:	rc	Keywords:	Triaged
Target Release:	---	Flags:	fweimer: needinfo? (cww)
Hardware:	x86_64
OS:	Linux
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Fixed In Version:		Doc Type:	If docs needed, set a value
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Clone Of:		Environment:
Last Closed:	2023-07-14 13:29:19 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Tim Zielke 2023-06-29 17:00:28 UTC

Description of problem:

I had a C executable that was using a char array of a size around 104857600. For example,

#define BUFFERMAX 104857600
   char     buffer[BUFFERMAX+1];   /* message buffer                */

The C executable ran fine on RHEL 7 Linux x86_64 machines. However, when we ported over to a RHEL 8 server, the program would just throw a "segmentation fault" when you tried to execute it. I recompiled the program with a lower value for the BUFFERMAX (i.e. 4194304), and now it runs fine on RHEL 8. I am fine with this workaround, but wanted to report the potential bug here for RHEL 8.

Version-Release number of selected component (if applicable):

Issue happened on the following:

REDHAT_BUGZILLA_PRODUCT="Red Hat Enterprise Linux 8"
REDHAT_BUGZILLA_PRODUCT_VERSION=8.8
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux"
REDHAT_SUPPORT_PRODUCT_VERSION="8.8"
Red Hat Enterprise Linux release 8.8 (Ootpa)


How reproducible:

Write a C program that has char array of around 104857600. See if it can run on both RHEL 7 and RHEL 8.


Steps to Reproduce:
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Actual results:


Expected results:


Additional info:

Comment 3 Carlos O'Donell 2023-06-30 13:24:46 UTC

If you are a Red Hat customer with an active subscription, please visit the Red Hat Customer Portal [1] for assistance with your issue.

[1] http://access.redhat.com/

Comment 5 Carlos O'Donell 2023-07-14 13:29:19 UTC

I'm marking this CLOSED/NOTABUG because there doesn't seem to be any direct issue with glibc, but rather a `ulimit -d` issue.

If you are a Red Hat customer with an active subscription, please reach out to your support representative.