From: DaeMyung Kang Date: Mon, 20 Apr 2026 17:51:25 +0000 (+0900) Subject: ksmbd: fix CreateOptions sanitization clobbering the whole field X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=5d115fa84027e4b999c3d3c7b1294849cf35cdb2;p=thirdparty%2Fkernel%2Fstable.git ksmbd: fix CreateOptions sanitization clobbering the whole field smb2_open() attempts to clear conflicting CreateOptions bits (FILE_SEQUENTIAL_ONLY_LE together with FILE_RANDOM_ACCESS_LE, and FILE_NO_COMPRESSION_LE on a directory open), but uses a plain assignment of the bitwise negation of the target flag: req->CreateOptions = ~(FILE_SEQUENTIAL_ONLY_LE); req->CreateOptions = ~(FILE_NO_COMPRESSION_LE); This replaces the entire field with 0xFFFFFFFB / 0xFFFFFFEF rather than clearing a single bit. With the SEQUENTIAL/RANDOM case, the next check for FILE_OPEN_BY_FILE_ID_LE | CREATE_TREE_CONNECTION | FILE_RESERVE_OPFILTER_LE then trivially matches and a legitimate request is rejected with -EOPNOTSUPP. With the NO_COMPRESSION case, every downstream test (FILE_DELETE_ON_CLOSE, etc.) operates on a corrupted CreateOptions value. Use &= ~FLAG to clear only the intended bit in both places. Signed-off-by: DaeMyung Kang Acked-by: Namjae Jeon Signed-off-by: Steve French --- diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c index a7abef1b208a..939089304052 100644 --- a/fs/smb/server/smb2pdu.c +++ b/fs/smb/server/smb2pdu.c @@ -3057,7 +3057,7 @@ int smb2_open(struct ksmbd_work *work) } else { if (req->CreateOptions & FILE_SEQUENTIAL_ONLY_LE && req->CreateOptions & FILE_RANDOM_ACCESS_LE) - req->CreateOptions = ~(FILE_SEQUENTIAL_ONLY_LE); + req->CreateOptions &= ~FILE_SEQUENTIAL_ONLY_LE; if (req->CreateOptions & (FILE_OPEN_BY_FILE_ID_LE | CREATE_TREE_CONNECTION | @@ -3071,7 +3071,7 @@ int smb2_open(struct ksmbd_work *work) rc = -EINVAL; goto err_out2; } else if (req->CreateOptions & FILE_NO_COMPRESSION_LE) { - req->CreateOptions = ~(FILE_NO_COMPRESSION_LE); + req->CreateOptions &= ~FILE_NO_COMPRESSION_LE; } } }