From fd9a2e1d513823e840960cb3bc26d8b7749d4ac2 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Mon, 6 Mar 2023 10:43:47 -0500 Subject: [PATCH 1/2] NFSD: Protect against filesystem freezing Flole observes this WARNING on occasion: [1210423.486503] WARNING: CPU: 8 PID: 1524732 at fs/ext4/ext4_jbd2.c:75 ext4_journal_check_start+0x68/0xb0 Reported-by: Suggested-by: Jan Kara Link: https://bugzilla.kernel.org/show_bug.cgi?id=217123 Fixes: 73da852e3831 ("nfsd: use vfs_iter_read/write") Reviewed-by: Jeff Layton Reviewed-by: Jan Kara Signed-off-by: Chuck Lever --- fs/nfsd/vfs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 21d5209f6e04..ba34a31a7c70 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1104,7 +1104,9 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf, since = READ_ONCE(file->f_wb_err); if (verf) nfsd_copy_write_verifier(verf, nn); + file_start_write(file); host_err = vfs_iter_write(file, &iter, &pos, flags); + file_end_write(file); if (host_err < 0) { nfsd_reset_write_verifier(nn); trace_nfsd_writeverf_reset(nn, rqstp, host_err); From 9ca6705d9d609441d34f8b853e1e4a6369b3b171 Mon Sep 17 00:00:00 2001 From: Benjamin Coddington Date: Fri, 3 Mar 2023 16:08:32 -0500 Subject: [PATCH 2/2] SUNRPC: Fix a server shutdown leak Fix a race where kthread_stop() may prevent the threadfn from ever getting called. If that happens the svc_rqst will not be cleaned up. Fixes: ed6473ddc704 ("NFSv4: Fix callback server shutdown") Signed-off-by: Benjamin Coddington Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever --- net/sunrpc/svc.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 1fd3f5e57285..fea7ce8fba14 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -798,6 +798,7 @@ svc_start_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs) static int svc_stop_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs) { + struct svc_rqst *rqstp; struct task_struct *task; unsigned int state = serv->sv_nrthreads-1; @@ -806,7 +807,10 @@ svc_stop_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs) task = choose_victim(serv, pool, &state); if (task == NULL) break; - kthread_stop(task); + rqstp = kthread_data(task); + /* Did we lose a race to svo_function threadfn? */ + if (kthread_stop(task) == -EINTR) + svc_exit_thread(rqstp); nrservs++; } while (nrservs < 0); return 0;