kernel.git/fs/smb/server, branch linux-6.15.y

smb/server: avoid deadlock when linking with ReplaceIfExists

2025-08-20T16:35:50Z

[ Upstream commit d5fc1400a34b4ea5e8f2ce296ea12bf8c8421694 ] If smb2_create_link() is called with ReplaceIfExists set and the name does exist then a deadlock will happen. ksmbd_vfs_kern_path_locked() will return with success and the parent directory will be locked. ksmbd_vfs_remove_file() will then remove the file. ksmbd_vfs_link() will then be called while the parent is still locked. It will try to lock the same parent and will deadlock. This patch moves the ksmbd_vfs_kern_path_unlock() call to *before* ksmbd_vfs_link() and then simplifies the code, removing the file_present flag variable. Signed-off-by: NeilBrown Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin

smb: server: Fix extension string in ksmbd_extract_shortname()

2025-08-15T10:17:05Z

commit 8e7d178d06e8937454b6d2f2811fa6a15656a214 upstream. In ksmbd_extract_shortname(), strscpy() is incorrectly called with the length of the source string (excluding the NUL terminator) rather than the size of the destination buffer. This results in "__" being copied to 'extension' rather than "___" (two underscores instead of three). Use the destination buffer size instead to ensure that the string "___" (three underscores) is copied correctly. Cc: stable@vger.kernel.org Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3") Signed-off-by: Thorsten Blum Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

ksmbd: limit repeated connections from clients with the same IP

2025-08-15T10:17:05Z

commit e6bb9193974059ddbb0ce7763fa3882bd60d4dc3 upstream. Repeated connections from clients with the same IP address may exhaust the max connections and prevent other normal client connections. This patch limit repeated connections from clients with the same IP. Reported-by: tianshuo han Cc: stable@vger.kernel.org Signed-off-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

ksmbd: fix corrupted mtime and ctime in smb2_open

2025-08-15T10:17:05Z

commit 4f8ff9486fd94b9d6a4932f2aefb9f2fc3bd0cf6 upstream. If STATX_BASIC_STATS flags are not given as an argument to vfs_getattr, It can not get ctime and mtime in kstat. This causes a problem showing mtime and ctime outdated from cifs.ko. File: /xfstest.test/foo Size: 4096 Blocks: 8 IO Block: 1048576 regular file Device: 0,65 Inode: 2033391 Links: 1 Access: (0755/-rwxr-xr-x) Uid: ( 0/ root) Gid: ( 0/ root) Context: system_u:object_r:cifs_t:s0 Access: 2025-07-23 22:15:30.136051900 +0100 Modify: 1970-01-01 01:00:00.000000000 +0100 Change: 1970-01-01 01:00:00.000000000 +0100 Birth: 2025-07-23 22:15:30.136051900 +0100 Cc: stable@vger.kernel.org Reported-by: David Howells Signed-off-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

ksmbd: fix Preauh_HashValue race condition

2025-08-15T10:17:04Z

commit 44a3059c4c8cc635a1fb2afd692d0730ca1ba4b6 upstream. If client send multiple session setup requests to ksmbd, Preauh_HashValue race condition could happen. There is no need to free sess->Preauh_HashValue at session setup phase. It can be freed together with session at connection termination phase. Cc: stable@vger.kernel.org Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-27661 Signed-off-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

ksmbd: fix null pointer dereference error in generate_encryptionkey

2025-08-15T10:17:04Z

commit 9b493ab6f35178afd8d619800df9071992f715de upstream. If client send two session setups with krb5 authenticate to ksmbd, null pointer dereference error in generate_encryptionkey could happen. sess->Preauth_HashValue is set to NULL if session is valid. So this patch skip generate encryption key if session is valid. Cc: stable@vger.kernel.org Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-27654 Signed-off-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman

smb: server: let recv_done() avoid touching data_transfer after cleanup/move

2025-08-15T10:17:02Z

[ Upstream commit a6c015b7ac2d8c5233337e5793f50d04fac17669 ] Calling enqueue_reassembly() and wake_up_interruptible(&t->wait_reassembly_queue) or put_receive_buffer() means the recvmsg/data_transfer pointer might get re-used by another thread, which means these should be the last operations before calling return. Cc: Namjae Jeon Cc: Steve French Cc: Tom Talpey Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Fixes: 0626e6641f6b ("cifsd: add server handler for central processing and tranport layers") Signed-off-by: Stefan Metzmacher Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin

smb: server: let recv_done() consistently call put_recvmsg/smb_direct_disconnect_rdma_connection

2025-08-15T10:17:02Z

[ Upstream commit cfe76fdbb9729c650f3505d9cfb2f70ddda2dbdc ] We should call put_recvmsg() before smb_direct_disconnect_rdma_connection() in order to call it before waking up the callers. In all error cases we should call smb_direct_disconnect_rdma_connection() in order to avoid stale connections. Cc: Namjae Jeon Cc: Steve French Cc: Tom Talpey Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Fixes: 0626e6641f6b ("cifsd: add server handler for central processing and tranport layers") Signed-off-by: Stefan Metzmacher Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin

smb: server: make sure we call ib_dma_unmap_single() only if we called ib_dma_map_single already

2025-08-15T10:17:02Z

[ Upstream commit afb4108c92898350e66b9a009692230bcdd2ac73 ] In case of failures either ib_dma_map_single() might not be called yet or ib_dma_unmap_single() was already called. We should make sure put_recvmsg() only calls ib_dma_unmap_single() if needed. Cc: Namjae Jeon Cc: Steve French Cc: Tom Talpey Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Fixes: 0626e6641f6b ("cifsd: add server handler for central processing and tranport layers") Signed-off-by: Stefan Metzmacher Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin

smb: server: remove separate empty_recvmsg_queue

2025-08-15T10:17:02Z

[ Upstream commit 01027a62b508c48c762096f347de925eedcbd008 ] There's no need to maintain two lists, we can just have a single list of receive buffers, which are free to use. Cc: Steve French Cc: Tom Talpey Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Fixes: 0626e6641f6b ("cifsd: add server handler for central processing and tranport layers") Signed-off-by: Stefan Metzmacher Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin