From 39946886fc865a4c26f1b3ea0805936db2d8986d Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Fri, 28 Feb 2020 12:22:59 +0300 Subject: [PATCH 1/3] cifs: potential unintitliazed error code in cifs_getattr() Smatch complains that "rc" could be uninitialized. fs/cifs/inode.c:2206 cifs_getattr() error: uninitialized symbol 'rc'. Changing it to "return 0;" improves readability as well. Fixes: cc1baf98c8f6 ("cifs: do not ignore the SYNC flags in getattr") Signed-off-by: Dan Carpenter Signed-off-by: Steve French Acked-by: Ronnie Sahlberg --- fs/cifs/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index 1e8a4b1579db..b16f8d23e97b 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -2191,7 +2191,7 @@ int cifs_getattr(const struct path *path, struct kstat *stat, if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID)) stat->gid = current_fsgid(); } - return rc; + return 0; } int cifs_fiemap(struct inode *inode, struct fiemap_extent_info *fei, u64 start, From 1be1fa42ebb73ad8fd67d2c846931361b4e3dd0a Mon Sep 17 00:00:00 2001 From: Shyam Prasad N Date: Mon, 9 Mar 2020 01:35:09 -0700 Subject: [PATCH 2/3] CIFS: Increment num_remote_opens stats counter even in case of smb2_query_dir_first The num_remote_opens counter keeps track of the number of open files which must be maintained by the server at any point. This is a per-tree-connect counter, and the value of this counter gets displayed in the /proc/fs/cifs/Stats output as a following... Open files: 0 total (local), 1 open on server ^^^^^^^^^^^^^^^^ As a thumb-rule, we want to increment this counter for each open/create that we successfully execute on the server. Similarly, we should decrement the counter when we successfully execute a close. In this case, an increment was being missed in case of smb2_query_dir_first, in case of successful open. As a result, we would underflow the counter and we could even see the counter go to negative after sufficient smb2_query_dir_first calls. I tested the stats counter for a bunch of filesystem operations with the fix. And it looks like the counter looks correct to me. I also check if we missed the increments and decrements elsewhere. It does not seem so. Few other cases where an open is done and we don't increment the counter are the compound calls where the corresponding close is also sent in the request. Signed-off-by: Shyam Prasad N CC: Stable Signed-off-by: Steve French Reviewed-by: Aurelien Aptel Reviewed-by: Pavel Shilovsky --- fs/cifs/smb2ops.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index c31e84ee3c39..3dddd20c5e2b 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -2222,6 +2222,8 @@ smb2_query_dir_first(const unsigned int xid, struct cifs_tcon *tcon, goto qdf_free; } + atomic_inc(&tcon->num_remote_opens); + qd_rsp = (struct smb2_query_directory_rsp *)rsp_iov[1].iov_base; if (qd_rsp->sync_hdr.Status == STATUS_NO_MORE_FILES) { trace_smb3_query_dir_done(xid, fid->persistent_fid, From 979a2665eb6c603ddce0ab374041ab101827b2e7 Mon Sep 17 00:00:00 2001 From: Murphy Zhou Date: Sat, 14 Mar 2020 11:38:31 +0800 Subject: [PATCH 3/3] CIFS: fiemap: do not return EINVAL if get nothing If we call fiemap on a truncated file with none blocks allocated, it makes sense we get nothing from this call. No output means no blocks have been counted, but the call succeeded. It's a valid response. Simple example reproducer: xfs_io -f 'truncate 2M' -c 'fiemap -v' /cifssch/testfile xfs_io: ioctl(FS_IOC_FIEMAP) ["/cifssch/testfile"]: Invalid argument Signed-off-by: Murphy Zhou Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky CC: Stable --- fs/cifs/smb2ops.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 3dddd20c5e2b..cfe9b800ea8c 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -3419,7 +3419,7 @@ static int smb3_fiemap(struct cifs_tcon *tcon, if (rc) goto out; - if (out_data_len < sizeof(struct file_allocated_range_buffer)) { + if (out_data_len && out_data_len < sizeof(struct file_allocated_range_buffer)) { rc = -EINVAL; goto out; }