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| author | Olivier Matz <olivier.matz@6wind.com> | 2019-06-06 10:15:19 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-11 13:22:46 +0300 |
| commit | efae37a44b4522855bbbfb2b17827346e79100e7 (patch) | |
| tree | 7d34f5adb3194b121d56422fa40fc817d285b835 /net/ipv6/raw.c | |
| parent | 32a64fb4519a069e687987f516efd8bd69a9fba2 (diff) | |
| download | linux-efae37a44b4522855bbbfb2b17827346e79100e7.tar.xz | |
ipv6: fix EFAULT on sendto with icmpv6 and hdrincl
[ Upstream commit b9aa52c4cb457e7416cc0c95f475e72ef4a61336 ]
The following code returns EFAULT (Bad address):
s = socket(AF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
setsockopt(s, SOL_IPV6, IPV6_HDRINCL, 1);
sendto(ipv6_icmp6_packet, addr); /* returns -1, errno = EFAULT */
The IPv4 equivalent code works. A workaround is to use IPPROTO_RAW
instead of IPPROTO_ICMPV6.
The failure happens because 2 bytes are eaten from the msghdr by
rawv6_probe_proto_opt() starting from commit 19e3c66b52ca ("ipv6
equivalent of "ipv4: Avoid reading user iov twice after
raw_probe_proto_opt""), but at that time it was not a problem because
IPV6_HDRINCL was not yet introduced.
Only eat these 2 bytes if hdrincl == 0.
Fixes: 715f504b1189 ("ipv6: add IPV6_HDRINCL option for raw sockets")
Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/ipv6/raw.c')
| -rw-r--r-- | net/ipv6/raw.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index bfa3dd3aaf15..b8d7100792b1 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -880,11 +880,14 @@ static int rawv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) opt = ipv6_fixup_options(&opt_space, opt); fl6.flowi6_proto = proto; - rfv.msg = msg; - rfv.hlen = 0; - err = rawv6_probe_proto_opt(&rfv, &fl6); - if (err) - goto out; + + if (!hdrincl) { + rfv.msg = msg; + rfv.hlen = 0; + err = rawv6_probe_proto_opt(&rfv, &fl6); + if (err) + goto out; + } if (!ipv6_addr_any(daddr)) fl6.daddr = *daddr; |