[PATCH 4/5] cifs: Fix parsing reparse point with native symlink in SMB1 non-UNICODE session

From: Pali Rohár
Date: Mon Oct 28 2024 - 07:14:55 EST


SMB1 NT_TRANSACT_IOCTL/FSCTL_GET_REPARSE_POINT even in non-UNICODE mode
returns reparse buffer in UNICODE/UTF-16 format.

This is because FSCTL_GET_REPARSE_POINT is NT-based IOCTL which does not
distinguish between 8-bit non-UNICODE and 16-bit UNICODE modes and its path
buffers are always encoded in UTF-16.

This change fixes reading of native symlinks in SMB1 when UNICODE session
is not active.

Fixes: ed3e0a149b58 ("smb: client: implement ->query_reparse_point() for SMB1")
Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
---
fs/smb/client/smb1ops.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index b0fb4a5c586d..f552951cfc04 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -1000,12 +1000,11 @@ static int cifs_parse_reparse_point(struct cifs_sb_info *cifs_sb,
{
struct reparse_data_buffer *buf;
TRANSACT_IOCTL_RSP *io = rsp_iov->iov_base;
- bool unicode = !!(io->hdr.Flags2 & SMBFLG2_UNICODE);
u32 plen = le16_to_cpu(io->ByteCount);

buf = (struct reparse_data_buffer *)((__u8 *)&io->hdr.Protocol +
le32_to_cpu(io->DataOffset));
- return parse_reparse_point(buf, plen, cifs_sb, full_path, unicode, data);
+ return parse_reparse_point(buf, plen, cifs_sb, full_path, true, data);
}

static bool
--
2.20.1