The module net:sunrpc:cache.c will effectively use
the same callback cache_ioctl for pointers passed from
file_operations.unlocked_ioctl and proc_ops.proc_ioctl and
it will expect pointers as the argument.
Thus to be able to pass CHERI capabilities, the .proc_ioctl
fp's arg input variable should also be of user_uintptr_t type.

The proc_compat_ioctl handler in the pci/proc.c module is
replaced with compat_noptr_ioctl as the arg is not being passed
as a pointer into the proc_bus_pci_ioctl handler.

Signed-off-by: Pawel Zalewski <pzalewski@thegoodpenguin.co.uk>
---
 drivers/pci/proc.c      | 4 ++--
 include/linux/proc_fs.h | 2 +-
 net/sunrpc/cache.c      | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c
index f967709082d6..a3cb37e49ab3 100644
--- a/drivers/pci/proc.c
+++ b/drivers/pci/proc.c
@@ -192,7 +192,7 @@ struct pci_filp_private {
 #endif /* HAVE_PCI_MMAP */

 static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
-                              unsigned long arg)
+                        user_uintptr_t arg)
 {
        struct pci_dev *dev = pde_data(file_inode(file));
 #ifdef HAVE_PCI_MMAP
@@ -322,7 +322,7 @@ static const struct proc_ops proc_bus_pci_ops = {
        .proc_write     = proc_bus_pci_write,
        .proc_ioctl     = proc_bus_pci_ioctl,
 #ifdef CONFIG_COMPAT
-       .proc_compat_ioctl = proc_bus_pci_ioctl,
+       .proc_compat_ioctl = compat_noptr_ioctl,
 #endif
 #ifdef HAVE_PCI_MMAP
        .proc_open      = proc_bus_pci_open,
diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
index 81d6e4ec2294..11d6c3620175 100644
--- a/include/linux/proc_fs.h
+++ b/include/linux/proc_fs.h
@@ -36,7 +36,7 @@ struct proc_ops {
        loff_t  (*proc_lseek)(struct file *, loff_t, int);
        int     (*proc_release)(struct inode *, struct file *);
        __poll_t (*proc_poll)(struct file *, struct poll_table_struct *);
-       long    (*proc_ioctl)(struct file *, unsigned int, unsigned long);
+       long    (*proc_ioctl)(struct file *, unsigned int, user_uintptr_t);
 #ifdef CONFIG_COMPAT
        long    (*proc_compat_ioctl)(struct file *, unsigned int, unsigned long);
 #endif
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index c4aaef5430f1..b682aa223bd6 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -1573,7 +1573,7 @@ static __poll_t cache_poll_procfs(struct file *filp, poll_table *wait)
 }

 static long cache_ioctl_procfs(struct file *filp,
-                              unsigned int cmd, unsigned long arg)
+                              unsigned int cmd, user_uintptr_t arg)
 {
        struct inode *inode = file_inode(filp);
        struct cache_detail *cd = pde_data(inode);
--
2.34.1