From ebbbc4bfad4cb355d17c671223d0814ee3ef4eda Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Thu, 5 Feb 2026 13:19:52 -0300 Subject: [PATCH] smb: client: fix potential UAF and double free in smb2_open_file() Zero out @err_iov and @err_buftype before retrying SMB2_open() to prevent an UAF bug if @data != NULL, otherwise a double free. Fixes: e3a43633023e ("smb/client: fix memory leak in smb2_open_file()") Reported-by: David Howells Closes: https://lore.kernel.org/r/2892312.1770306653@warthog.procyon.org.uk Signed-off-by: Paulo Alcantara (Red Hat) Reviewed-by: David Howells Reviewed-by: ChenXiaoSong Cc: linux-cifs@vger.kernel.org Signed-off-by: Steve French --- fs/smb/client/smb2file.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/smb/client/smb2file.c b/fs/smb/client/smb2file.c index 2dd08388ea873..1f7f284a78449 100644 --- a/fs/smb/client/smb2file.c +++ b/fs/smb/client/smb2file.c @@ -179,6 +179,8 @@ int smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms, &err_buftype); if (rc == -EACCES && retry_without_read_attributes) { free_rsp_buf(err_buftype, err_iov.iov_base); + memset(&err_iov, 0, sizeof(err_iov)); + err_buftype = CIFS_NO_BUFFER; oparms->desired_access &= ~FILE_READ_ATTRIBUTES; rc = SMB2_open(xid, oparms, smb2_path, &smb2_oplock, smb2_data, NULL, &err_iov, &err_buftype); -- 2.47.3