2021-10-15 01:18:55

by Gabriel Krisman Bertazi

Subject: [PATCH v7 12/28] fanotify: Support null inode event in fanotify_dfid_inode

FAN_FS_ERROR doesn't support DFID, but this function is still called for
every event. The problem is that it is not capable of handling null
inodes, which now can happen in case of superblock error events. For
this case, just returning dir will be enough.

Signed-off-by: Gabriel Krisman Bertazi <[email protected]>
---
fs/notify/fanotify/fanotify.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index c620b4f6fe12..397ee623ff1e 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -452,7 +452,7 @@ static struct inode *fanotify_dfid_inode(u32 event_mask, const void *data,
if (event_mask & ALL_FSNOTIFY_DIRENT_EVENTS)
return dir;

- if (S_ISDIR(inode->i_mode))
+ if (inode && S_ISDIR(inode->i_mode))
return inode;

return dir;
--
2.33.0

2021-10-15 08:22:09

by Amir Goldstein

Subject: Re: [PATCH v7 12/28] fanotify: Support null inode event in fanotify_dfid_inode

On Fri, Oct 15, 2021 at 12:38 AM Gabriel Krisman Bertazi
<[email protected]> wrote:
>
> FAN_FS_ERROR doesn't support DFID, but this function is still called for
> every event. The problem is that it is not capable of handling null
> inodes, which now can happen in case of superblock error events. For
> this case, just returning dir will be enough.
>
> Signed-off-by: Gabriel Krisman Bertazi <[email protected]>
Reviewed-by: Amir Goldstein <[email protected]>


Please also fortify fsnotify_handle_inode_event() against calling
->handle_inode_event() with NULL inode.

> ---
> fs/notify/fanotify/fanotify.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
> index c620b4f6fe12..397ee623ff1e 100644
> --- a/fs/notify/fanotify/fanotify.c
> +++ b/fs/notify/fanotify/fanotify.c
> @@ -452,7 +452,7 @@ static struct inode *fanotify_dfid_inode(u32 event_mask, const void *data,
> if (event_mask & ALL_FSNOTIFY_DIRENT_EVENTS)
> return dir;
>
> - if (S_ISDIR(inode->i_mode))
> + if (inode && S_ISDIR(inode->i_mode))
> return inode;
>
> return dir;
> --
> 2.33.0
>

2021-10-15 16:15:57

by Jan Kara

Subject: Re: [PATCH v7 12/28] fanotify: Support null inode event in fanotify_dfid_inode

On Thu 14-10-21 18:36:30, Gabriel Krisman Bertazi wrote:
> FAN_FS_ERROR doesn't support DFID, but this function is still called for
> every event. The problem is that it is not capable of handling null
> inodes, which now can happen in case of superblock error events. For
> this case, just returning dir will be enough.
>
> Signed-off-by: Gabriel Krisman Bertazi <[email protected]>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <[email protected]>

Honza

> ---
> fs/notify/fanotify/fanotify.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
> index c620b4f6fe12..397ee623ff1e 100644
> --- a/fs/notify/fanotify/fanotify.c
> +++ b/fs/notify/fanotify/fanotify.c
> @@ -452,7 +452,7 @@ static struct inode *fanotify_dfid_inode(u32 event_mask, const void *data,
> if (event_mask & ALL_FSNOTIFY_DIRENT_EVENTS)
> return dir;
>
> - if (S_ISDIR(inode->i_mode))
> + if (inode && S_ISDIR(inode->i_mode))
> return inode;
>
> return dir;
> --
> 2.33.0
>
--
Jan Kara <[email protected]>
SUSE Labs, CR