AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

tcp: beware of alignments in tcp_get_info()

Browse Source 
With some combinations of user provided flags in netlink command,
it is possible to call tcp_get_info() with a buffer that is not 8-bytes
aligned.

It does matter on some arches, so we need to use put_unaligned() to
store the u64 fields.

Current iproute2 package does not trigger this particular issue.

Fixes: 0df48c26d8 ("tcp: add tcpi_bytes_acked to tcp_info")
Fixes: 977cb0ecf8 ("tcp: add pacing_rate information into tcp_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2016-01-27 10:52:43 -08:00 committed by David S. Miller
parent 4f2c6ae5c6
commit ff5d749772
1 changed files with 8 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
net/ipv4/tcp.c
View File

@ -279,6 +279,7 @@
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <asm/unaligned.h>
#include <net/busy_poll.h>
int sysctl_tcp_fin_timeout __read_mostly = TCP_FIN_TIMEOUT;
@ -2638,6 +2639,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
const struct inet_connection_sock *icsk = inet_csk(sk);
u32 now = tcp_time_stamp;
unsigned int start;
u64 rate64;
u32 rate;
memset(info, 0, sizeof(*info));
@ -2703,15 +2705,17 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
info->tcpi_total_retrans = tp->total_retrans;
rate = READ_ONCE(sk->sk_pacing_rate);
info->tcpi_pacing_rate = rate != ~0U ? rate : ~0ULL;
rate64 = rate != ~0U ? rate : ~0ULL;
put_unaligned(rate64, &info->tcpi_pacing_rate);
rate = READ_ONCE(sk->sk_max_pacing_rate);
info->tcpi_max_pacing_rate = rate != ~0U ? rate : ~0ULL;
rate64 = rate != ~0U ? rate : ~0ULL;
put_unaligned(rate64, &info->tcpi_max_pacing_rate);
do {
start = u64_stats_fetch_begin_irq(&tp->syncp);
info->tcpi_bytes_acked = tp->bytes_acked;
info->tcpi_bytes_received = tp->bytes_received;
put_unaligned(tp->bytes_acked, &info->tcpi_bytes_acked);
put_unaligned(tp->bytes_received, &info->tcpi_bytes_received);
} while (u64_stats_fetch_retry_irq(&tp->syncp, start));
info->tcpi_segs_out = tp->segs_out;
info->tcpi_segs_in = tp->segs_in;