6.9-stable review patch. If anyone has any objections, please let me know.
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From: Hobin Woo hobin.woo@samsung.com
commit e2e33caa5dc2eae7bddf88b22ce11ec3d760e5cd upstream.
may_open() does not allow a directory to be opened with the write access. However, some writing flags set by client result in adding write access on server, making ksmbd incompatible with FUSE file system. Simply, let's discard the write access when opening a directory.
list_add corruption. next is NULL. ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:26! pc : __list_add_valid+0x88/0xbc lr : __list_add_valid+0x88/0xbc Call trace: __list_add_valid+0x88/0xbc fuse_finish_open+0x11c/0x170 fuse_open_common+0x284/0x5e8 fuse_dir_open+0x14/0x24 do_dentry_open+0x2a4/0x4e0 dentry_open+0x50/0x80 smb2_open+0xbe4/0x15a4 handle_ksmbd_work+0x478/0x5ec process_one_work+0x1b4/0x448 worker_thread+0x25c/0x430 kthread+0x104/0x1d4 ret_from_fork+0x10/0x20
Cc: stable@vger.kernel.org Signed-off-by: Yoonho Shin yoonho.shin@samsung.com Signed-off-by: Hobin Woo hobin.woo@samsung.com Acked-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/smb/server/smb2pdu.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
--- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -2051,15 +2051,22 @@ out_err1: * @access: file access flags * @disposition: file disposition flags * @may_flags: set with MAY_ flags + * @is_dir: is creating open flags for directory * * Return: file open flags */ static int smb2_create_open_flags(bool file_present, __le32 access, __le32 disposition, - int *may_flags) + int *may_flags, + bool is_dir) { int oflags = O_NONBLOCK | O_LARGEFILE;
+ if (is_dir) { + access &= ~FILE_WRITE_DESIRE_ACCESS_LE; + ksmbd_debug(SMB, "Discard write access to a directory\n"); + } + if (access & FILE_READ_DESIRED_ACCESS_LE && access & FILE_WRITE_DESIRE_ACCESS_LE) { oflags |= O_RDWR; @@ -3167,7 +3174,9 @@ int smb2_open(struct ksmbd_work *work)
open_flags = smb2_create_open_flags(file_present, daccess, req->CreateDisposition, - &may_flags); + &may_flags, + req->CreateOptions & FILE_DIRECTORY_FILE_LE || + (file_present && S_ISDIR(d_inode(path.dentry)->i_mode)));
if (!test_tree_conn_flag(tcon, KSMBD_TREE_CONN_FLAG_WRITABLE)) { if (open_flags & (O_CREAT | O_TRUNC)) {