5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx> [ Upstream commit 272531ac619b374ab474e989eb387162fded553f ] Instead of failing, encode an invalid file handle in fanotify_encode_fh if no inode is provided. This bogus file handle will be reported by FAN_FS_ERROR for non-inode errors. Link: https://lore.kernel.org/r/20211025192746.66445-16-krisman@xxxxxxxxxxxxx Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx> Reviewed-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx> Signed-off-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> --- fs/notify/fanotify/fanotify.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index ec84fee7ad01c..c64d61b673caf 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -370,8 +370,14 @@ static int fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode, fh->type = FILEID_ROOT; fh->len = 0; fh->flags = 0; + + /* + * Invalid FHs are used by FAN_FS_ERROR for errors not + * linked to any inode. The f_handle won't be reported + * back to userspace. + */ if (!inode) - return 0; + goto out; /* * !gpf means preallocated variable size fh, but fh_len could @@ -403,6 +409,7 @@ static int fanotify_encode_fh(struct fanotify_fh *fh, struct inode *inode, fh->type = type; fh->len = fh_len; +out: /* * Mix fh into event merge key. Hash might be NULL in case of * unhashed FID events (i.e. FAN_FS_ERROR). -- 2.43.0