5.10-stable review patch. If anyone has any objections, please let me know.
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From: Gabriel Krisman Bertazi krisman@collabora.com
[ 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@collabora.com Reviewed-by: Amir Goldstein amir73il@gmail.com Reviewed-by: Jan Kara jack@suse.cz Signed-off-by: Gabriel Krisman Bertazi krisman@collabora.com Signed-off-by: Jan Kara jack@suse.cz Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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).