From 1f4bbedd4e5a69b01cde2cc21d01151ab2d0884f Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Thu, 8 May 2025 16:46:11 +0900 Subject: [PATCH 1/3] ksmbd: fix stream write failure If there is no stream data in file, v_len is zero. So, If position(*pos) is zero, stream write will fail due to stream write position validation check. This patch reorganize stream write position validation. Fixes: 0ca6df4f40cf ("ksmbd: prevent out-of-bounds stream writes by validating *pos") Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/smb/server/vfs.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c index 482eba0f4dc1..156ded9ac889 100644 --- a/fs/smb/server/vfs.c +++ b/fs/smb/server/vfs.c @@ -409,10 +409,15 @@ static int ksmbd_vfs_stream_write(struct ksmbd_file *fp, char *buf, loff_t *pos, ksmbd_debug(VFS, "write stream data pos : %llu, count : %zd\n", *pos, count); + if (*pos >= XATTR_SIZE_MAX) { + pr_err("stream write position %lld is out of bounds\n", *pos); + return -EINVAL; + } + size = *pos + count; if (size > XATTR_SIZE_MAX) { size = XATTR_SIZE_MAX; - count = (*pos + count) - XATTR_SIZE_MAX; + count = XATTR_SIZE_MAX - *pos; } v_len = ksmbd_vfs_getcasexattr(idmap, @@ -426,13 +431,6 @@ static int ksmbd_vfs_stream_write(struct ksmbd_file *fp, char *buf, loff_t *pos, goto out; } - if (v_len <= *pos) { - pr_err("stream write position %lld is out of bounds (stream length: %zd)\n", - *pos, v_len); - err = -EINVAL; - goto out; - } - if (v_len < size) { wbuf = kvzalloc(size, KSMBD_DEFAULT_GFP); if (!wbuf) { From 68477b5dc57108d4306c56b3842d6f80a8161f30 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Wed, 21 May 2025 17:07:36 +0900 Subject: [PATCH 2/3] ksmbd: fix rename failure I found that rename fails after cifs mount due to update of lookup_one_qstr_excl(). mv a/c b/ mv: cannot move 'a/c' to 'b/c': No such file or directory In order to rename to a new name regardless of whether the dentry is negative, we need to get the dentry through lookup_one_qstr_excl(). So It will not return error if the name doesn't exist. Fixes: 204a575e91f3 ("VFS: add common error checks to lookup_one_qstr_excl()") Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/smb/server/vfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c index 156ded9ac889..baf0d3031a44 100644 --- a/fs/smb/server/vfs.c +++ b/fs/smb/server/vfs.c @@ -682,7 +682,7 @@ int ksmbd_vfs_rename(struct ksmbd_work *work, const struct path *old_path, struct ksmbd_file *parent_fp; int new_type; int err, lookup_flags = LOOKUP_NO_SYMLINKS; - int target_lookup_flags = LOOKUP_RENAME_TARGET; + int target_lookup_flags = LOOKUP_RENAME_TARGET | LOOKUP_CREATE; if (ksmbd_override_fsids(work)) return -ENOMEM; From 10379171f346e6f61d30d9949500a8de4336444a Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Tue, 20 May 2025 09:25:03 +0900 Subject: [PATCH 3/3] ksmbd: use list_first_entry_or_null for opinfo_get_list() The list_first_entry() macro never returns NULL. If the list is empty then it returns an invalid pointer. Use list_first_entry_or_null() to check if the list is empty. Reported-by: kernel test robot Reported-by: Dan Carpenter Closes: https://lore.kernel.org/r/202505080231.7OXwq4Te-lkp@intel.com/ Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/smb/server/oplock.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/fs/smb/server/oplock.c b/fs/smb/server/oplock.c index 03f606afad93..d7a8a580d013 100644 --- a/fs/smb/server/oplock.c +++ b/fs/smb/server/oplock.c @@ -146,12 +146,9 @@ static struct oplock_info *opinfo_get_list(struct ksmbd_inode *ci) { struct oplock_info *opinfo; - if (list_empty(&ci->m_op_list)) - return NULL; - down_read(&ci->m_lock); - opinfo = list_first_entry(&ci->m_op_list, struct oplock_info, - op_entry); + opinfo = list_first_entry_or_null(&ci->m_op_list, struct oplock_info, + op_entry); if (opinfo) { if (opinfo->conn == NULL || !atomic_inc_not_zero(&opinfo->refcount))