Bug 1139805

Summary: rpm badly handles failed write() to stdout
Product: Red Hat Enterprise Linux 6 Reporter: Karl Hastings <kasmith>
Component: rpmAssignee: Packaging Maintenance Team <packaging-team-maint>
Status: CLOSED ERRATA QA Contact: Marek Marusic <mmarusic>
Severity: medium Docs Contact:
Priority: medium    
Version: 6.5CC: extras-qa, ffesti, jherrman, jonstanley, jzeleny, ksrot, lkardos, mmarusic, novyjindrich, packaging-team-maint, pmatilai, rvokal
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: rpm-4.8.0-46.el6 Doc Type: Bug Fix
Doc Text:
If the standard output of the rpm utility was redirected to a file and the file system was full, rpm failed without writing any error messages. Now, rpm prints an error message as a standard error output if the described scenario occurs.
 Story Points: ---
Clone Of: 1139444
: 1202753 1597274 (view as bug list) Environment:
Last Closed: 2015-07-22 07:03:20 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:
Bug Depends On: 1139444    
Bug Blocks: 1075802    

Description Karl Hastings 2014-09-09 16:40:06 UTC 
+++ This bug was initially created as a clone of Bug #1139444 +++

Description of problem:

If stdout is being redirected to a file, and the filesystem is full, rpm will silently fail despite write() returning -ENOSPC

<much snippage from strace>
write(1, "grep-2.18-1.fc20.x86_64\n", 24) = -1 ENOSPC (No space left on device)

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

rpm-4.11.2-2.fc20.x86_64

How reproducible: 100%

Steps to Reproduce:
1. Make a filesystem, fill it up (I used a small loopback filesystem to reproduce)
2. rpm -qa > testfile
3. Watch the file either not have all of the expected output (i.e. writes succeeded prior to -ENOSPC) or be 0 bytes

rpm should inform the user about the error, as other utilities do. For example:

$ id  > /mnt/test/test14
id: write error: No space left on device

--- Additional comment from Jon Stanley on 2014-09-08 19:04:50 EDT ---

Forgot to list the actual problematic sequence of commands, but you could probably figure it out. But for completeness sake:

$ rpm -qa > /mnt/test/test15 ; echo $?
0
$ ls -l /mnt/test/test15
-rw-rw-r--. 1 jstanley jstanley 0 Sep  8 19:02 /mnt/test/test15

--- Additional comment from Panu Matilainen on 2014-09-09 06:25:23 EDT ---

Yup... from the rpm logging function:

    (void) fputs(rpmlogLevelPrefix(rec->pri), msgout);

    (void) fputs(rec->message, msgout);
    (void) fflush(msgout);

These go back 14 years almost to date, the (void) warning silencers are half a year younger so its not exactly a new bug :) Thanks for reporting though.

--- Additional comment from Panu Matilainen on 2014-09-09 06:40:31 EDT ---

Just FWIW, rpmlog() does not return an error code, so without API-changes this is fixable only to the extent of logging an error from the logger function ... unless the error came from writing to stderr, in which case reporting an error is going to be a bit difficult anyway.

--- Additional comment from Jon Stanley on 2014-09-09 11:19:13 EDT ---

Hmm, if I'm reading this correctly that means that there's no way for the rpm command to exit with a non-zero exit code without API changes?
Comment 3 Florian Festi 2014-12-15 15:14:46 UTC 
ACK to issuing an error message (if the problem is not stderr). As stated above changing the API to pass a return code is out of question.
Comment 9 errata-xmlrpc 2015-07-22 07:03:20 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2015-1452.html