diff options
| author | Eric Dumazet <edumazet@google.com> | 2023-09-18 14:23:21 +0000 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2023-09-19 18:21:44 +0200 |
| commit | fa17a6d8a5bd0cd7565b613cb804242cd0f6b7ab (patch) | |
| tree | 47b212f49ee830235b382165cf734328cdff2e00 /include | |
| parent | 6a23c555f7eb436d6799533675ffa179db3d5834 (diff) | |
ipv6: lockless IPV6_ADDR_PREFERENCES implementation
We have data-races while reading np->srcprefs
Switch the field to a plain byte, add READ_ONCE()
and WRITE_ONCE() annotations where needed,
and IPV6_ADDR_PREFERENCES setsockopt() can now be lockless.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230918142321.1794107-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/ipv6.h | 2 | ||||
| -rw-r--r-- | include/net/ip6_route.h | 5 | ||||
| -rw-r--r-- | include/net/ipv6.h | 20 |
3 files changed, 10 insertions, 17 deletions
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h index 09253825c99c..e400ff757f13 100644 --- a/include/linux/ipv6.h +++ b/include/linux/ipv6.h @@ -243,7 +243,7 @@ struct ipv6_pinfo { } rxopt; /* sockopt flags */ - __u8 srcprefs:3; /* 001: prefer temporary address + __u8 srcprefs; /* 001: prefer temporary address * 010: prefer public address * 100: prefer care-of address */ diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h index b1ea49900b4a..28b065790261 100644 --- a/include/net/ip6_route.h +++ b/include/net/ip6_route.h @@ -53,13 +53,12 @@ struct route_info { */ static inline int rt6_srcprefs2flags(unsigned int srcprefs) { - /* No need to bitmask because srcprefs have only 3 bits. */ - return srcprefs << 3; + return (srcprefs & IPV6_PREFER_SRC_MASK) << 3; } static inline unsigned int rt6_flags2srcprefs(int flags) { - return (flags >> 3) & 7; + return (flags >> 3) & IPV6_PREFER_SRC_MASK; } static inline bool rt6_need_strict(const struct in6_addr *daddr) diff --git a/include/net/ipv6.h b/include/net/ipv6.h index bd115980809f..b3444c8a6f74 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -1306,10 +1306,13 @@ static inline void ip6_sock_set_recverr(struct sock *sk) inet6_set_bit(RECVERR6, sk); } -static inline int __ip6_sock_set_addr_preferences(struct sock *sk, int val) +#define IPV6_PREFER_SRC_MASK (IPV6_PREFER_SRC_TMP | IPV6_PREFER_SRC_PUBLIC | \ + IPV6_PREFER_SRC_COA) + +static inline int ip6_sock_set_addr_preferences(struct sock *sk, int val) { + unsigned int prefmask = ~IPV6_PREFER_SRC_MASK; unsigned int pref = 0; - unsigned int prefmask = ~0; /* check PUBLIC/TMP/PUBTMP_DEFAULT conflicts */ switch (val & (IPV6_PREFER_SRC_PUBLIC | @@ -1359,20 +1362,11 @@ static inline int __ip6_sock_set_addr_preferences(struct sock *sk, int val) return -EINVAL; } - inet6_sk(sk)->srcprefs = (inet6_sk(sk)->srcprefs & prefmask) | pref; + WRITE_ONCE(inet6_sk(sk)->srcprefs, + (READ_ONCE(inet6_sk(sk)->srcprefs) & prefmask) | pref); return 0; } -static inline int ip6_sock_set_addr_preferences(struct sock *sk, int val) -{ - int ret; - - lock_sock(sk); - ret = __ip6_sock_set_addr_preferences(sk, val); - release_sock(sk); - return ret; -} - static inline void ip6_sock_set_recvpktinfo(struct sock *sk) { lock_sock(sk); |