Fix: race upon task->real_parent accessing #171
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get_process_socket() and smith_get_pid_tree() could grab a task_struct which is being released, i.e. increment task->usage while it's already zero-valued. The race window is very small. The solution is: don't increment task->usage if it's already zero to avoid the race conditions. Any access of task->real_parent also has the same risk of races, but not fatal, only gets inconsistent data. Signed-off-by: shenping.matt <shenping.matt@bytedance.com>
EBWi11
approved these changes
Jan 20, 2022
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get_process_socket() and smith_get_pid_tree() could grab a task_struct
which is being released, i.e. increment task->usage while it's already
zero-valued. The race window is very small.
The solution is: don't increment task->usage if it's already zero to
avoid the race conditions. Any access of task->real_parent also has
the same risk of races, but not fatal, only gets inconsistent data.
Signed-off-by: shenping.matt shenping.matt@bytedance.com
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