projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| 495c55a2 GKH |
1 | From b7e5034cbecf5a65b7bfdc2b20a8378039577706 Mon Sep 17 00:00:00 2001 |
| 2 | From: "J. Bruce Fields" <bfields@redhat.com> | |
| 3 | Date: Wed, 20 Feb 2019 12:54:50 -0500 | |
| 4 | Subject: svcrpc: fix UDP on servers with lots of threads | |
| 5 | ||
| 6 | From: J. Bruce Fields <bfields@redhat.com> | |
| 7 | ||
| 8 | commit b7e5034cbecf5a65b7bfdc2b20a8378039577706 upstream. | |
| 9 | ||
| 10 | James Pearson found that an NFS server stopped responding to UDP | |
| 11 | requests if started with more than 1017 threads. | |
| 12 | ||
| 13 | sv_max_mesg is about 2^20, so that is probably where the calculation | |
| 14 | performed by | |
| 15 | ||
| 16 | svc_sock_setbufsize(svsk->sk_sock, | |
| 17 | (serv->sv_nrthreads+3) * serv->sv_max_mesg, | |
| 18 | (serv->sv_nrthreads+3) * serv->sv_max_mesg); | |
| 19 | ||
| 20 | starts to overflow an int. | |
| 21 | ||
| 22 | Reported-by: James Pearson <jcpearson@gmail.com> | |
| 23 | Tested-by: James Pearson <jcpearson@gmail.com> | |
| 24 | Cc: stable@vger.kernel.org | |
| 25 | Signed-off-by: J. Bruce Fields <bfields@redhat.com> | |
| 26 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 27 | ||
| 28 | --- | |
| 29 | net/sunrpc/svcsock.c | 20 ++++++++++---------- | |
| 30 | 1 file changed, 10 insertions(+), 10 deletions(-) | |
| 31 | ||
| 32 | --- a/net/sunrpc/svcsock.c | |
| 33 | +++ b/net/sunrpc/svcsock.c | |
| 34 | @@ -381,12 +381,16 @@ static int svc_partial_recvfrom(struct s | |
| 35 | /* | |
| 36 | * Set socket snd and rcv buffer lengths | |
| 37 | */ | |
| 38 | -static void svc_sock_setbufsize(struct socket *sock, unsigned int snd, | |
| 39 | - unsigned int rcv) | |
| 40 | +static void svc_sock_setbufsize(struct svc_sock *svsk, unsigned int nreqs) | |
| 41 | { | |
| 42 | + unsigned int max_mesg = svsk->sk_xprt.xpt_server->sv_max_mesg; | |
| 43 | + struct socket *sock = svsk->sk_sock; | |
| 44 | + | |
| 45 | + nreqs = min(nreqs, INT_MAX / 2 / max_mesg); | |
| 46 | + | |
| 47 | lock_sock(sock->sk); | |
| 48 | - sock->sk->sk_sndbuf = snd * 2; | |
| 49 | - sock->sk->sk_rcvbuf = rcv * 2; | |
| 50 | + sock->sk->sk_sndbuf = nreqs * max_mesg * 2; | |
| 51 | + sock->sk->sk_rcvbuf = nreqs * max_mesg * 2; | |
| 52 | sock->sk->sk_write_space(sock->sk); | |
| 53 | release_sock(sock->sk); | |
| 54 | } | |
| 55 | @@ -548,9 +552,7 @@ static int svc_udp_recvfrom(struct svc_r | |
| 56 | * provides an upper bound on the number of threads | |
| 57 | * which will access the socket. | |
| 58 | */ | |
| 59 | - svc_sock_setbufsize(svsk->sk_sock, | |
| 60 | - (serv->sv_nrthreads+3) * serv->sv_max_mesg, | |
| 61 | - (serv->sv_nrthreads+3) * serv->sv_max_mesg); | |
| 62 | + svc_sock_setbufsize(svsk, serv->sv_nrthreads + 3); | |
| 63 | ||
| 64 | clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); | |
| 65 | skb = NULL; | |
| 66 | @@ -718,9 +720,7 @@ static void svc_udp_init(struct svc_sock | |
| 67 | * receive and respond to one request. | |
| 68 | * svc_udp_recvfrom will re-adjust if necessary | |
| 69 | */ | |
| 70 | - svc_sock_setbufsize(svsk->sk_sock, | |
| 71 | - 3 * svsk->sk_xprt.xpt_server->sv_max_mesg, | |
| 72 | - 3 * svsk->sk_xprt.xpt_server->sv_max_mesg); | |
| 73 | + svc_sock_setbufsize(svsk, 3); | |
| 74 | ||
| 75 | /* data might have come in before data_ready set up */ | |
| 76 | set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); |