Messages in this thread | | | Date | Wed, 15 Aug 2012 20:17:11 +0200 | From | Oleg Nesterov <> | Subject | Re: yama_ptrace_access_check(): possible recursive locking detected |
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On 08/15, Kees Cook wrote: > > It sounds like get_task_comm shouldn't have locking at all then? It > should just do a length-limited copy
Without task_lock() get_task_comm() can copy incomplete new name.
Honestly, I do not know any user which "strictly" needs the correct name. may be proc.
> and make sure there is a trailing > 0-byte?
get_task_comm()->strncpy() should always see (and copy) 0-byte. comm[TASK_COMM_LEN - 1] == '\0' and this byte is never changed.
set_task_comm()->strlcpy() can write to this byte, but it can only write 0 again.
Or I am totally confused ;)
Oleg.
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