From e38b3f20059426a0adbde014ff71071739ab5226 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 30 Aug 2021 08:36:34 +1000 Subject: SUNRPC: don't pause on incomplete allocation alloc_pages_bulk_array() attempts to allocate at least one page based on the provided pages, and then opportunistically allocates more if that can be done without dropping the spinlock. So if it returns fewer than requested, that could just mean that it needed to drop the lock. In that case, try again immediately. Only pause for a time if no progress could be made. Reported-and-tested-by: Mike Javorski Reported-and-tested-by: Lothar Paltins Fixes: f6e70aab9dfe ("SUNRPC: refresh rq_pages using a bulk page allocator") Signed-off-by: NeilBrown Acked-by: Mel Gorman Signed-off-by: Chuck Lever --- net/sunrpc/svc_xprt.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'net') diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 682058a5ec13..796eebf1787d 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -663,7 +663,7 @@ static int svc_alloc_arg(struct svc_rqst *rqstp) { struct svc_serv *serv = rqstp->rq_server; struct xdr_buf *arg = &rqstp->rq_arg; - unsigned long pages, filled; + unsigned long pages, filled, ret; pagevec_init(&rqstp->rq_pvec); @@ -675,11 +675,12 @@ static int svc_alloc_arg(struct svc_rqst *rqstp) pages = RPCSVC_MAXPAGES; } - for (;;) { - filled = alloc_pages_bulk_array(GFP_KERNEL, pages, - rqstp->rq_pages); - if (filled == pages) - break; + for (filled = 0; filled < pages; filled = ret) { + ret = alloc_pages_bulk_array(GFP_KERNEL, pages, + rqstp->rq_pages); + if (ret > filled) + /* Made progress, don't sleep yet */ + continue; set_current_state(TASK_INTERRUPTIBLE); if (signalled() || kthread_should_stop()) { -- cgit v1.2.3 From 0c217d5066c84f67cd672cf03ec8f682e5d013c2 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Thu, 2 Sep 2021 09:30:37 +1000 Subject: SUNRPC: improve error response to over-size gss credential When the NFS server receives a large gss (kerberos) credential and tries to pass it up to rpc.svcgssd (which is deprecated), it triggers an infinite loop in cache_read(). cache_request() always returns -EAGAIN, and this causes a "goto again". This patch: - changes the error to -E2BIG to avoid the infinite loop, and - generates a WARN_ONCE when rsi_request first sees an over-sized credential. The warning suggests switching to gssproxy. Link: https://bugzilla.kernel.org/show_bug.cgi?id=196583 Signed-off-by: NeilBrown Signed-off-by: Chuck Lever --- net/sunrpc/auth_gss/svcauth_gss.c | 2 ++ net/sunrpc/cache.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c index 3d685fe328fa..475a965b7b43 100644 --- a/net/sunrpc/auth_gss/svcauth_gss.c +++ b/net/sunrpc/auth_gss/svcauth_gss.c @@ -194,6 +194,8 @@ static void rsi_request(struct cache_detail *cd, qword_addhex(bpp, blen, rsii->in_handle.data, rsii->in_handle.len); qword_addhex(bpp, blen, rsii->in_token.data, rsii->in_token.len); (*bpp)[-1] = '\n'; + WARN_ONCE(*blen < 0, + "RPCSEC/GSS credential too large - please use gssproxy\n"); } static int rsi_parse(struct cache_detail *cd, diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c index 1a2c1c44bb00..59641803472c 100644 --- a/net/sunrpc/cache.c +++ b/net/sunrpc/cache.c @@ -803,7 +803,7 @@ static int cache_request(struct cache_detail *detail, detail->cache_request(detail, crq->item, &bp, &len); if (len < 0) - return -EAGAIN; + return -E2BIG; return PAGE_SIZE - len; } -- cgit v1.2.3