[patch 07/18] vmur: reject open on z/VM reader files with status HOLD

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Michael Holzheu <[email protected]>

If a reader file with HOLD status is at the top of the reader queue, currently
all read requests will return data of the second file in the queue. But the
semantics of vmur is that always the topmost file is read. With this fix
-EPERM is returned on open, if the topmost reader file is in HOLD status.

Signed-off-by: Michael Holzheu <[email protected]>
Signed-off-by: Martin Schwidefsky <[email protected]>
---

 drivers/s390/char/vmur.c |    4 +++-
 drivers/s390/char/vmur.h |    4 +++-
 2 files changed, 6 insertions(+), 2 deletions(-)

Index: quilt-2.6/drivers/s390/char/vmur.c
===================================================================
--- quilt-2.6.orig/drivers/s390/char/vmur.c
+++ quilt-2.6/drivers/s390/char/vmur.c
@@ -556,7 +556,9 @@ static int verify_device(struct urdev *u
 		rc = diag_read_next_file_info(&fcb, 0);
 		if (rc)
 			return rc;
-
+		/* if file is in hold status, we do not read it */
+		if (fcb.file_stat & (FLG_SYSTEM_HOLD | FLG_USER_HOLD))
+			return -EPERM;
 		/* open file on virtual reader	*/
 		buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 		if (!buf)
Index: quilt-2.6/drivers/s390/char/vmur.h
===================================================================
--- quilt-2.6.orig/drivers/s390/char/vmur.h
+++ quilt-2.6/drivers/s390/char/vmur.h
@@ -50,7 +50,9 @@ struct file_control_block {
 	char  rest[200];
 } __attribute__ ((packed));
 
-#define FLG_CP_DUMP 0x10
+#define FLG_SYSTEM_HOLD	0x04
+#define FLG_CP_DUMP	0x10
+#define FLG_USER_HOLD	0x20
 
 /*
  * A struct urdev is created for each ur device that is made available

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux