Merged revisions 228693 via svnmerge from

https://origsvn.digium.com/svn/asterisk/trunk

................
  r228693 | dvossel | 2009-11-06 16:35:44 -0600 (Fri, 06 Nov 2009) | 16 lines
  
  Merged revisions 228692 via svnmerge from 
  https://origsvn.digium.com/svn/asterisk/branches/1.4
  
  ........
    r228692 | dvossel | 2009-11-06 16:33:27 -0600 (Fri, 06 Nov 2009) | 9 lines
    
    fixes audiohook write crash occuring in chan_spy whisper mode.
    
    After writing to the audiohook list in ast_write(), frames
    were being freed incorrectly.  Under certain conditions this
    resulted in a double free crash.
    
    (closes issue #16133)
    Reported by: wetwired
  ........
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git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.1@228695 65c4cc65-6c06-0410-ace0-fbb531ad65f3
This commit is contained in:
David Vossel
2009-11-06 22:37:35 +00:00
parent 4413bd2360
commit 19bff2b866

View File

@@ -3464,6 +3464,11 @@ int ast_write(struct ast_channel *chan, struct ast_frame *fr)
if (chan->audiohooks) {
struct ast_frame *prev = NULL, *new_frame, *cur, *dup;
int freeoldlist = 0;
if (f != fr) {
freeoldlist = 1;
}
/* Since ast_audiohook_write may return a new frame, and the cur frame is
* an item in a list of frames, create a new list adding each cur frame back to it
@@ -3474,13 +3479,16 @@ int ast_write(struct ast_channel *chan, struct ast_frame *fr)
/* if this frame is different than cur, preserve the end of the list,
* free the old frames, and set cur to be the new frame */
if (new_frame != cur) {
/* doing an ast_frisolate here seems silly, but we are not guaranteed the new_frame
* isn't part of local storage, meaning if ast_audiohook_write is called multiple
* times it may override the previous frame we got from it unless we dup it */
if ((dup = ast_frisolate(new_frame))) {
AST_LIST_NEXT(dup, frame_list) = AST_LIST_NEXT(cur, frame_list);
ast_frfree(new_frame);
ast_frfree(cur);
if (freeoldlist) {
AST_LIST_NEXT(cur, frame_list) = NULL;
ast_frfree(cur);
}
cur = dup;
}
}