mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-07 19:30:30 +09:00
staging/lustre/lov: remove set_fs() call from lov_getstripe()
commit 0a33252e06 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@intel.com>
Reviewed-on: http://review.whamcloud.com/6150
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3221
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Li Wei <wei.g.li@intel.com>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
committed by
Greg Kroah-Hartman
parent
bd2e8f0a72
commit
a365c707d2
@@ -399,18 +399,10 @@ int lov_getstripe(struct obd_export *exp, struct lov_stripe_md *lsm,
|
||||
struct lov_mds_md *lmmk = NULL;
|
||||
int rc, 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) */
|
||||
lum_size = sizeof(struct lov_user_md_v1);
|
||||
@@ -485,6 +477,5 @@ int lov_getstripe(struct obd_export *exp, struct lov_stripe_md *lsm,
|
||||
|
||||
obd_free_diskmd(exp, &lmmk);
|
||||
out_set:
|
||||
set_fs(seg);
|
||||
return rc;
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user