Johnothan King bb3527aea5 Fix infinite loop when posix_spawn fails (re: 0863a8eb) (#468) ... This commit fixes an infinite loop introduced in commit 0863a8eb that caused ksh to enter an infinite loop if posix_spawn failed to start a new process after setting the terminal process group. Reproducer (warning: it will cause ksh to crash Wayland sessions and drives up CPU usage by a ton): $ /tmp/this/file/does/not/exist /usr/bin/ksh: /tmp/this/file/does/not/exist: not found $ <Press enter> (ksh now prints $PS1 in a loop until killed with SIGKILL) The first bug fixed is the infinite loop that occurs when posix_spawn fails to execute a command. This was fixed by setting the terminal process group to the main interactive shell. The second bug fixed is related to the signal handling of the SIGTTIN, SIGTTOU and SIGTSTP signals. In sh_ntfork() these signals are set to their default signal handlers (SIG_DFL) before running a command. The signal handlers were only restored to SIG_IGN (ignore signal) when sh_ntfork() successfully ran a command. This could cause a SIGTTOU lockup under strace when a command failed to execute in an interactive shell, while also being one cause of the infinite loop. src/cmd/ksh93/sh/xec.c: sh_ntfork(): - Restore the terminal process group if posix_spawn failed to launch a new process. This is necessary because posix_spawn will set the terminal process group before it attempts to run a command and doesn't restore it on failure.		2022-03-11 21:14:20 +01:00
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builtin	iffe: really abort on output{ fail (re: e20c0c6b, e72543a, b6bd981)	2022-01-01 02:28:27 +00:00
INIT	Update copyright years in files changed since 1st Jan 2022	2022-01-30 20:49:04 +00:00
ksh93	Fix infinite loop when posix_spawn fails (re: 0863a8eb) (#468)	2022-03-11 21:14:20 +01:00
Mamfile	**/Mamfile: add header comment pointing to MAM docs (re: 6cc2f6a0)	2021-01-25 14:38:58 +00:00