This is a note to let you know that I've just added the patch titled
staging/lustre/lov: remove set_fs() call from lov_getstripe()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
staging-lustre-lov-remove-set_fs-call-from-lov_getstripe.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0a33252e060e97ed3fbdcec9517672f1e91aaef3 Mon Sep 17 00:00:00 2001
From: Oleg Drokin <green@xxxxxxxxxxxxxx>
Date: Fri, 26 May 2017 23:40:33 -0400
Subject: staging/lustre/lov: remove set_fs() call from lov_getstripe()
From: Oleg Drokin <green@xxxxxxxxxxxxxx>
commit 0a33252e060e97ed3fbdcec9517672f1e91aaef3 upstream.
lov_getstripe() calls set_fs(KERNEL_DS) so that it can handle a struct
lov_user_md pointer from user- or kernel-space. This changes the
behavior of copy_from_user() on SPARC and may result in a misaligned
access exception which in turn oopses the kernel. In fact the
relevant argument to lov_getstripe() is never called with a
kernel-space pointer and so changing the address limits is unnecessary
and so we remove the calls to save, set, and restore the address
limits.
Signed-off-by: John L. Hammond <john.hammond@xxxxxxxxx>
Reviewed-on: http://review.whamcloud.com/6150
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3221
Reviewed-by: Andreas Dilger <andreas.dilger@xxxxxxxxx>
Reviewed-by: Li Wei <wei.g.li@xxxxxxxxx>
Signed-off-by: Oleg Drokin <green@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/lustre/lustre/lov/lov_pack.c | 9 ---------
1 file changed, 9 deletions(-)
--- a/drivers/staging/lustre/lustre/lov/lov_pack.c
+++ b/drivers/staging/lustre/lustre/lov/lov_pack.c
@@ -387,18 +387,10 @@ int lov_getstripe(struct lov_object *obj
struct lov_mds_md *lmmk = NULL;
int rc, lmmk_size, lmm_size;
int lum_size;
- mm_segment_t seg;
if (!lsm)
return -ENODATA;
- /*
- * "Switch to kernel segment" to allow copying from kernel space by
- * copy_{to,from}_user().
- */
- seg = get_fs();
- set_fs(KERNEL_DS);
-
/* we only need the header part from user space to get lmm_magic and
* lmm_stripe_count, (the header part is common to v1 and v3)
*/
@@ -478,6 +470,5 @@ int lov_getstripe(struct lov_object *obj
out_free:
kfree(lmmk);
out:
- set_fs(seg);
return rc;
}
Patches currently in stable-queue which might be from green@xxxxxxxxxxxxxx are
queue-4.9/staging-lustre-lov-remove-set_fs-call-from-lov_getstripe.patch