Merge branch 'for-linus' into for-next

Back-merge of 6.14 devel branch for further developments of TAS
codecsBack-merge of 6.14 devel branch for further developments.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 11 insertions, 2 deletions

diff --git a/fs/pidfs.c b/fs/pidfs.c
index 049352f973de..c0478b3c55d9 100644
--- a/fs/pidfs.c
+++ b/fs/pidfs.c
@@ -287,7 +287,6 @@ static bool pidfs_ioctl_valid(unsigned int cmd)
 	switch (cmd) {
 	case FS_IOC_GETVERSION:
 	case PIDFD_GET_CGROUP_NAMESPACE:
-	case PIDFD_GET_INFO:
 	case PIDFD_GET_IPC_NAMESPACE:
 	case PIDFD_GET_MNT_NAMESPACE:
 	case PIDFD_GET_NET_NAMESPACE:
@@ -300,6 +299,17 @@ static bool pidfs_ioctl_valid(unsigned int cmd)
 		return true;
 	}
 
+	/* Extensible ioctls require some more careful checks. */
+	switch (_IOC_NR(cmd)) {
+	case _IOC_NR(PIDFD_GET_INFO):
+		/*
+		 * Try to prevent performing a pidfd ioctl when someone
+		 * erronously mistook the file descriptor for a pidfd.
+		 * This is not perfect but will catch most cases.
+		 */
+		return (_IOC_TYPE(cmd) == _IOC_TYPE(PIDFD_GET_INFO));
+	}
+
 	return false;
 }
 
@@ -511,7 +521,6 @@ static char *pidfs_dname(struct dentry *dentry, char *buffer, int buflen)
 }
 
 const struct dentry_operations pidfs_dentry_operations = {
-	.d_delete	= always_delete_dentry,
 	.d_dname	= pidfs_dname,
 	.d_prune	= stashed_dentry_prune,
 };