File descriptor may leak in all libnl versions if pthreads are used.

[Марк Коренберг]

lib/nl.c:

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sk->s_fd = socket(AF_NETLINK, SOCK_RAW, protocol);
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should be changed to

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sk->s_fd = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, protocol);
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Note: SOCK_CLOEXEC should be checked in autotools via querying
fcntl(fd, F_GETFD) & FD_CLOEXEC)  after calling to socket() with
SOCK_CLOEXEC

-- 
Segmentation fault