tree 66b36cd6c485ea989a634ab49cc937dc5451ba3d
parent fba1296624bf95fc07057da1e26beee8a733180c
author Eric Dumazet <edumazet@google.com> 1474419977 -0700
committer David S. Miller <davem@davemloft.net> 1474526477 -0400

net: get rid of an signed integer overflow in ip_idents_reserve()

Jiri Pirko reported an UBSAN warning happening in ip_idents_reserve()

[] UBSAN: Undefined behaviour in ./arch/x86/include/asm/atomic.h:156:11
[] signed integer overflow:
[] -2117905507 + -695755206 cannot be represented in type 'int'

Since we do not have uatomic_add_return() yet, use atomic_cmpxchg()
so that the arithmetics can be done using unsigned int.

Fixes: 04ca6973f7c1 ("ip: make IP identifiers less predictable")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>