Description of problem: trying a test script from the dash mailing list that has ambiguous behavior (do heredocs always start with the first newline, or only with the first newline not embedded inside another shell word): $ ksh <<\EOF prefix() { sed -e "s/^/$1:/"; } DASH_CODE() { :; } prefix A <<XXX && echo "$(prefix B <<XXX echo line 1 XXX echo line 2)" && prefix DASH_CODE <<DASH_CODE echo line 3 XXX echo line 4)" echo line 5 DASH_CODE EOF The crash doesn't happen every time, so it is a data-dependent race. When it doesn't crash, I can't explain the output: B:echo line 1 line 2 && prefix DASH_CODE <<DASH_CODE echo line 3 XXX echo line 4) line 5 Version-Release number of selected component: ksh-20120801-27.fc23 Additional info: reporter: libreport-2.6.4 backtrace_rating: 4 cmdline: ksh crash_function: regionof executable: /usr/bin/ksh global_pid: 9928 kernel: 4.3.5-300.fc23.x86_64 runlevel: N 5 type: CCpp uid: 14986 Truncated backtrace: Thread no. 1 (10 frames) #0 regionof at /usr/src/debug/ksh-20120801/src/lib/libast/vmalloc/malloc.c:347 #1 free at /usr/src/debug/ksh-20120801/src/lib/libast/vmalloc/malloc.c:594 #2 here_copy at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/lex.c:2042 #4 sh_lex at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/lex.c:488 #5 comsub at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/lex.c:1623 #6 sh_lex at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/lex.c:875 #7 simple at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/parse.c:1496 #8 item at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/parse.c:1354 #9 term at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/parse.c:577 #10 list at /usr/src/debug/ksh-20120801/src/cmd/ksh93/sh/parse.c:550
Created attachment 1129933 [details] File: backtrace
Created attachment 1129934 [details] File: cgroup
Created attachment 1129935 [details] File: core_backtrace
Created attachment 1129936 [details] File: dso_list
Created attachment 1129937 [details] File: environ
Created attachment 1129938 [details] File: exploitable
Created attachment 1129939 [details] File: limits
Created attachment 1129940 [details] File: maps
Created attachment 1129941 [details] File: mountinfo
Created attachment 1129942 [details] File: namespaces
Created attachment 1129943 [details] File: open_fds
Created attachment 1129944 [details] File: proc_pid_status
Created attachment 1129945 [details] File: var_log_messages
This package has changed ownership in the Fedora Package Database. Reassigning to the new owner of this component.
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