Re: [PATCH v8 25/32] fanotify: Report fid entry even for zero-length file_handle
From: Amir Goldstein <amir73il@gmail.com>
Date: 2021-10-19 06:14:10
Also in:
linux-ext4, linux-fsdevel
On Tue, Oct 19, 2021 at 3:03 AM Gabriel Krisman Bertazi [off-list ref] wrote:
Non-inode errors will reported with an empty file_handle. In preparation for that, allow some events to print the FID record even if there isn't any file_handle encoded Even though FILEID_ROOT is used internally, make zero-length file handles be reported as FILEID_INVALID. Signed-off-by: Gabriel Krisman Bertazi <redacted>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
quoted hunk ↗ jump to hunk
--- fs/notify/fanotify/fanotify_user.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index ae848306a017..cd962deefeb7 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c@@ -339,9 +339,6 @@ static int copy_fid_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh, pr_debug("%s: fh_len=%zu name_len=%zu, info_len=%zu, count=%zu\n", __func__, fh_len, name_len, info_len, count); - if (!fh_len) - return 0; - if (WARN_ON_ONCE(len < sizeof(info) || len > count)) return -EFAULT;@@ -376,6 +373,11 @@ static int copy_fid_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh, handle.handle_type = fh->type; handle.handle_bytes = fh_len; + + /* Mangle handle_type for bad file_handle */ + if (!fh_len) + handle.handle_type = FILEID_INVALID; + if (copy_to_user(buf, &handle, sizeof(handle))) return -EFAULT; --2.33.0