lwp: fix pid leak on exec failure before task startup

When msh tries to execute a non-ELF path, lwp_execve() may allocate a PID
before lwp_load() fails. The old error path only dropped the LWP reference,
leaving the PID tree entry pointing to a freed LWP.

In an init-less boot flow, this can poison pid 1 after a failed command from
msh. A later LWP launch may then treat the stale pid 1 entry as a valid parent
LWP, resulting in invalid pgrp/session state and a job-control assertion during
process exit.

Add lwp_pid_rollback() for exec/spawn failures before the process becomes
runnable. Unlike lwp_pid_put(), it always releases the PID lock and does not
enter the "no more pid allocation" state when the PID tree becomes empty.

Use the rollback helper in lwp_execve() failure paths after PID allocation.

Signed-off-by: zhangyang <[email protected]>

0 files changed, 0 insertions, 0 deletions