kernel/git/stable/linux.git/fs/cifs, branch linux-5.5.y

CIFS: Fix bug which the return value by asynchronous read is error

2020-04-17T14:12:07+00:00

commit 97adda8b3ab703de8e4c8d27646ddd54fe22879c upstream. This patch is used to fix the bug in collect_uncached_read_data() that rc is automatically converted from a signed number to an unsigned number when the CIFS asynchronous read fails. It will cause ctx->rc is error. Example: Share a directory and create a file on the Windows OS. Mount the directory to the Linux OS using CIFS. On the CIFS client of the Linux OS, invoke the pread interface to deliver the read request. The size of the read length plus offset of the read request is greater than the maximum file size. In this case, the CIFS server on the Windows OS returns a failure message (for example, the return value of smb2.nt_status is STATUS_INVALID_PARAMETER). After receiving the response message, the CIFS client parses smb2.nt_status to STATUS_INVALID_PARAMETER and converts it to the Linux error code (rdata->result=-22). Then the CIFS client invokes the collect_uncached_read_data function to assign the value of rdata->result to rc, that is, rc=rdata->result=-22. The type of the ctx->total_len variable is unsigned integer, the type of the rc variable is integer, and the type of the ctx->rc variable is ssize_t. Therefore, during the ternary operation, the value of rc is automatically converted to an unsigned number. The final result is ctx->rc=4294967274. However, the expected result is ctx->rc=-22. Signed-off-by: Yilu Lin Signed-off-by: Steve French CC: Stable Acked-by: Ronnie Sahlberg Signed-off-by: Greg Kroah-Hartman

smb3: fix performance regression with setting mtime

2020-04-17T14:12:07+00:00

commit cf5371ae460eb8e484e4884747af270c86c3c469 upstream. There are cases when we don't want to send the SMB2 flush operation (e.g. when user specifies mount parm "nostrictsync") and it can be a very expensive operation on the server. In most cases in order to set mtime, we simply need to flush (write) the dirtry pages from the client and send the writes to the server not also send a flush protocol operation to the server. Fixes: aa081859b10c ("cifs: flush before set-info if we have writeable handles") CC: Stable Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

CIFS: fiemap: do not return EINVAL if get nothing

2020-03-25T07:27:04+00:00

commit 979a2665eb6c603ddce0ab374041ab101827b2e7 upstream. 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 Signed-off-by: Greg Kroah-Hartman

cifs: add missing mount option to /proc/mounts

2020-03-25T07:26:54+00:00

[ Upstream commit ec57010acd03428a749d2600bf09bd537eaae993 ] We were not displaying the mount option "signloosely" in /proc/mounts for cifs mounts which some users found confusing recently Signed-off-by: Steve French Reviewed-by: Aurelien Aptel Signed-off-by: Sasha Levin

cifs: fix potential mismatch of UNC paths

2020-03-25T07:26:54+00:00

[ Upstream commit 154255233830e1e4dd0d99ac929a5dce588c0b81 ] Ensure that full_path is an UNC path that contains '\\' as delimiter, which is required by cifs_build_devname(). The build_path_from_dentry_optional_prefix() function may return a path with '/' as delimiter when using SMB1 UNIX extensions, for example. Signed-off-by: Paulo Alcantara (SUSE) Signed-off-by: Steve French Acked-by: Ronnie Sahlberg Signed-off-by: Sasha Levin

locks: reinstate locks_delete_block optimization

2020-03-25T07:26:53+00:00

[ Upstream commit dcf23ac3e846ca0cf626c155a0e3fcbbcf4fae8a ] There is measurable performance impact in some synthetic tests due to commit 6d390e4b5d48 (locks: fix a potential use-after-free problem when wakeup a waiter). Fix the race condition instead by clearing the fl_blocker pointer after the wake_up, using explicit acquire/release semantics. This does mean that we can no longer use the clearing of fl_blocker as the wait condition, so switch the waiters over to checking whether the fl_blocked_member list_head is empty. Reviewed-by: yangerkun Reviewed-by: NeilBrown Fixes: 6d390e4b5d48 (locks: fix a potential use-after-free problem when wakeup a waiter) Signed-off-by: Jeff Layton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

cifs_atomic_open(): fix double-put on late allocation failure

2020-03-18T06:19:10+00:00

commit d9a9f4849fe0c9d560851ab22a85a666cddfdd24 upstream. several iterations of ->atomic_open() calling conventions ago, we used to need fput() if ->atomic_open() failed at some point after successful finish_open(). Now (since 2016) it's not needed - struct file carries enough state to make fput() work regardless of the point in struct file lifecycle and discarding it on failure exits in open() got unified. Unfortunately, I'd missed the fact that we had an instance of ->atomic_open() (cifs one) that used to need that fput(), as well as the stale comment in finish_open() demanding such late failure handling. Trivially fixed... Fixes: fe9ec8291fca "do_last(): take fput() on error after opening to out:" Cc: stable@kernel.org # v4.7+ Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman

cifs: fix rename() by ensuring source handle opened with DELETE bit

2020-03-12T06:18:30+00:00

commit 86f740f2aed5ea7fe1aa86dc2df0fb4ab0f71088 upstream. To rename a file in SMB2 we open it with the DELETE access and do a special SetInfo on it. If the handle is missing the DELETE bit the server will fail the SetInfo with STATUS_ACCESS_DENIED. We currently try to reuse any existing opened handle we have with cifs_get_writable_path(). That function looks for handles with WRITE access but doesn't check for DELETE, making rename() fail if it finds a handle to reuse. Simple reproducer below. To select handles with the DELETE bit, this patch adds a flag argument to cifs_get_writable_path() and find_writable_file() and the existing 'bool fsuid_only' argument is converted to a flag. The cifsFileInfo struct only stores the UNIX open mode but not the original SMB access flags. Since the DELETE bit is not mapped in that mode, this patch stores the access mask in cifs_fid on file open, which is accessible from cifsFileInfo. Simple reproducer: #include #include #include #include #include #include #define E(s) perror(s), exit(1) int main(int argc, char *argv[]) { int fd, ret; if (argc != 3) { fprintf(stderr, "Usage: %s A B\n" "create&open A in write mode, " "rename A to B, close A\n", argv[0]); return 0; } fd = openat(AT_FDCWD, argv[1], O_WRONLY|O_CREAT|O_SYNC, 0666); if (fd == -1) E("openat()"); ret = rename(argv[1], argv[2]); if (ret) E("rename()"); ret = close(fd); if (ret) E("close()"); return ret; } $ gcc -o bugrename bugrename.c $ ./bugrename /mnt/a /mnt/b rename(): Permission denied Fixes: 8de9e86c67ba ("cifs: create a helper to find a writeable handle by path name") CC: Stable Signed-off-by: Aurelien Aptel Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky Reviewed-by: Paulo Alcantara (SUSE) Signed-off-by: Greg Kroah-Hartman

cifs: don't leak -EAGAIN for stat() during reconnect

2020-03-12T06:18:30+00:00

commit fc513fac56e1b626ae48a74d7551d9c35c50129e upstream. If from cifs_revalidate_dentry_attr() the SMB2/QUERY_INFO call fails with an error, such as STATUS_SESSION_EXPIRED, causing the session to be reconnected it is possible we will leak -EAGAIN back to the application even for system calls such as stat() where this is not a valid error. Fix this by re-trying the operation from within cifs_revalidate_dentry_attr() if cifs_get_inode_info*() returns -EAGAIN. This fixes stat() and possibly also other system calls that uses cifs_revalidate_dentry*(). Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French Reviewed-by: Pavel Shilovsky Reviewed-by: Aurelien Aptel CC: Stable Signed-off-by: Greg Kroah-Hartman

cifs: Fix mode output in debugging statements

2020-03-05T15:45:12+00:00

[ Upstream commit f52aa79df43c4509146140de0241bc21a4a3b4c7 ] A number of the debug statements output file or directory mode in hex. Change these to print using octal. Signed-off-by: Frank Sorenson Signed-off-by: Steve French Signed-off-by: Sasha Levin