[PATCH] file: modify struct fown_struct to use a struct pid

File handles can be requested to send sigio and sigurg to processes.  By
tracking the destination processes using struct pid instead of pid_t we make
the interface safe from all potential pid wrap around problems.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 1 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 2e29a2edaeec..91c0b2a32a90 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -684,7 +684,8 @@ extern struct block_device *I_BDEV(struct inode *inode);
 
 struct fown_struct {
         rwlock_t lock;          /* protects pid, uid, euid fields */
-        int pid;                /* pid or -pgrp where SIGIO should be sent */
+        struct pid *pid;        /* pid or -pgrp where SIGIO should be sent */
+        enum pid_type pid_type; /* Kind of process group SIGIO should be sent to */
         uid_t uid, euid;        /* uid/euid of process setting the owner */
         int signum;             /* posix.1b rt signal to be delivered on IO */
 };
@@ -880,8 +881,10 @@ extern void kill_fasync(struct fasync_struct **, int, int);
 /* only for net: no internal synchronization */
 extern void __kill_fasync(struct fasync_struct *, int, int);
 
+extern int __f_setown(struct file *filp, struct pid *, enum pid_type, int force);
 extern int f_setown(struct file *filp, unsigned long arg, int force);
 extern void f_delown(struct file *filp);
+extern pid_t f_getown(struct file *filp);
 extern int send_sigurg(struct fown_struct *fown);
 
 /*