Re: [PATCH] staging/lustre/lov: remove set_fs() call from lov_getstripe()
On May 29, 2017, at 10:28 AM, Greg Kroah-Hartman wrote: > On Fri, May 26, 2017 at 11:40:33PM -0400, Oleg Drokin wrote: >> 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 >> Reviewed-on: http://review.whamcloud.com/6150 >> Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3221 >> Reviewed-by: Andreas Dilger >> Reviewed-by: Li Wei >> Signed-off-by: Oleg Drokin >> --- >> drivers/staging/lustre/lustre/lov/lov_pack.c | 9 - >> 1 file changed, 9 deletions(-) > > So is this the patch that you want applied to the staging tree(s) as > well? If so, please let me know, otherwise I have no clue… Yes, this is it. Thanks!
Re: [PATCH] staging/lustre/lov: remove set_fs() call from lov_getstripe()
On Fri, May 26, 2017 at 11:40:33PM -0400, Oleg Drokin wrote: > 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 > Reviewed-on: http://review.whamcloud.com/6150 > Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3221 > Reviewed-by: Andreas Dilger > Reviewed-by: Li Wei > Signed-off-by: Oleg Drokin > --- > drivers/staging/lustre/lustre/lov/lov_pack.c | 9 - > 1 file changed, 9 deletions(-) So is this the patch that you want applied to the staging tree(s) as well? If so, please let me know, otherwise I have no clue... Come on, you know better than this... greg k-h
[PATCH] staging/lustre/lov: remove set_fs() call from lov_getstripe()
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
Reviewed-on: http://review.whamcloud.com/6150
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3221
Reviewed-by: Andreas Dilger
Reviewed-by: Li Wei
Signed-off-by: Oleg Drokin
---
drivers/staging/lustre/lustre/lov/lov_pack.c | 9 -
1 file changed, 9 deletions(-)
diff --git a/drivers/staging/lustre/lustre/lov/lov_pack.c
b/drivers/staging/lustre/lustre/lov/lov_pack.c
index 2e1bd47..e6727ce 100644
--- a/drivers/staging/lustre/lustre/lov/lov_pack.c
+++ b/drivers/staging/lustre/lustre/lov/lov_pack.c
@@ -293,18 +293,10 @@ int lov_getstripe(struct lov_object *obj, struct
lov_stripe_md *lsm,
size_t lmmk_size;
size_t lum_size;
int rc;
- 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);
-
if (lsm->lsm_magic != LOV_MAGIC_V1 && lsm->lsm_magic != LOV_MAGIC_V3) {
CERROR("bad LSM MAGIC: 0x%08X != 0x%08X nor 0x%08X\n",
lsm->lsm_magic, LOV_MAGIC_V1, LOV_MAGIC_V3);
@@ -406,6 +398,5 @@ int lov_getstripe(struct lov_object *obj, struct
lov_stripe_md *lsm,
out_free:
kvfree(lmmk);
out:
- set_fs(seg);
return rc;
}
--
2.9.3
