[asterisk-bugs] [Asterisk 0015181]: file convert leaks input file descriptor

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=15181 
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Reported By:                jkroon
Assigned To:                russell
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Project:                    Asterisk
Issue ID:                   15181
Category:                   Resources/res_convert
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
Asterisk Version:           1.6.0.9 
Regression:                 No 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2009-05-22 09:18 CDT
Last Modified:              2009-05-25 05:39 CDT
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Summary:                    file convert leaks input file descriptor
Description: 
when issueing a file convert it seems that asterisk is leaking the input
file descriptor.  As a test I copied a .g729 file into /tmp
(/tmp/test.g729), the rest follows:

gabriel ~ # ls -l /tmp/test.* 
-rw-r--r-- 1 root root 3380 May 22 16:10 /tmp/test.g729
gabriel ~ # ls -l /proc/$(pidof asterisk)/fd/ | grep test 
gabriel ~ # asterisk -rx "file convert /tmp/test.g729 /tmp/test.wav"
Converted /tmp/test.g729 to /tmp/test.wav in 12ms
gabriel ~ # ls -l /proc/$(pidof asterisk)/fd/ | grep test
lrwx------ 1 asterisk asterisk 64 May 22 16:10 179 -> /tmp/test.g729
gabriel ~ # ls -l /tmp/test.*
-rw-r--r-- 1 root     root      3380 May 22 16:10 /tmp/test.g729
-rw-r--r-- 1 asterisk asterisk 54124 May 22 16:12 /tmp/test.wav
gabriel ~ # 

I'll take a peek at the code a little later, for now I just need to have
it reported.  I don't think this was the case in 1.6.0.3 but I'll need to
go find an installation to confirm.
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 (0105366) jkroon (reporter) - 2009-05-25 05:39
 https://issues.asterisk.org/view.php?id=15181#c105366 
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Ok, I think I managed to figure out what's going on, please do confirm. 
Based on a diff of 1.6.0.3 and 1.6.0.9 res/res_convert.c is identical. 
However, main/file.c has changed a little.  In particular, there were
changes made to ast_closestream, in particular, a large block of code was
replaced with this:

+	if (ast_test_flag(&f->fr, AST_FRFLAG_FROM_FILESTREAM)) {
+		/* If this flag is still set, it essentially means that the reference
+		 * count of f is non-zero. We can't destroy this filestream until
+		 * whatever is using the filestream's frame has finished.
+		 *
+		 * Since this was called, however, we need to remove the reference
from
+		 * when this filestream was first allocated. That way, when the
embedded
+		 * frame is freed, the refcount will reach 0 and we can finish
destroying
+		 * this filestream properly.
+		 */
+		ao2_ref(f, -1);
+		return 0;


Which is basically checking the same reference flag that is being
incremented in ast_readframe.  The appropriate function apparently to
decrement this reference counter is ast_filestream_frame_freed.

As a side note btw, the entire ast_closestream (unless test_flag has side
effects) can be reduced to ao2_ref(f, -1); return 0;, however, that is not
related to the issue at hand, I think.

I suspect the ast_filestream_frame_freed function needs to be called from
somewhere, I'm just not 100 % sure from where. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-05-25 05:39 jkroon         Note Added: 0105366                          
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