From: Rohith Surabattula rohiths@microsoft.com
[ Upstream commit 06a466565d54a1a42168f9033a062a3f5c40e73b ]
When session gets reconnected during mount then read size in super block fs context gets set to zero and after negotiate, rsize is not modified which results in incorrect read with requested bytes as zero. Fixes intermittent failure of xfstest generic/240
Note that stable requires a different version of this patch which will be sent to the stable mailing list.
Signed-off-by: Rohith Surabattula rohiths@microsoft.com Acked-by: Paulo Alcantara (SUSE) pc@cjr.nz Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/cifs/cifsfs.c | 3 +++ fs/cifs/file.c | 10 ++++++++++ 2 files changed, 13 insertions(+)
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index 21bf82fc2278..ba6f536d76de 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -210,6 +210,9 @@ cifs_read_super(struct super_block *sb) if (rc) goto out_no_root; /* tune readahead according to rsize if readahead size not set on mount */ + if (cifs_sb->ctx->rsize == 0) + cifs_sb->ctx->rsize = + tcon->ses->server->ops->negotiate_rsize(tcon, cifs_sb->ctx); if (cifs_sb->ctx->rasize) sb->s_bdi->ra_pages = cifs_sb->ctx->rasize / PAGE_SIZE; else diff --git a/fs/cifs/file.c b/fs/cifs/file.c index 82bbaf8e92b7..b23f6b489bb9 100644 --- a/fs/cifs/file.c +++ b/fs/cifs/file.c @@ -3734,6 +3734,11 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file, break; }
+ if (cifs_sb->ctx->rsize == 0) + cifs_sb->ctx->rsize = + server->ops->negotiate_rsize(tlink_tcon(open_file->tlink), + cifs_sb->ctx); + rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize, &rsize, credits); if (rc) @@ -4512,6 +4517,11 @@ static int cifs_readpages(struct file *file, struct address_space *mapping, break; }
+ if (cifs_sb->ctx->rsize == 0) + cifs_sb->ctx->rsize = + server->ops->negotiate_rsize(tlink_tcon(open_file->tlink), + cifs_sb->ctx); + rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize, &rsize, credits); if (rc)