Bob Peterson 36e4ad0316 GFS2: don't set rgrp gl_object until it's inserted into rgrp tree ... Before this patch, function read_rindex_entry would set a rgrp glock's gl_object pointer to itself before inserting the rgrp into the rgrp rbtree. The problem is: if another process was also reading the rgrp in, and had already inserted its newly created rgrp, then the second call to read_rindex_entry would overwrite that value, then return a bad return code to the caller. Later, other functions would reference the now-freed rgrp memory by way of gl_object. In some cases, that could result in gfs2_rgrp_brelse being called twice for the same rgrp: once for the failed attempt and once for the "real" rgrp release. Eventually the kernel would panic. There are also a number of other things that could go wrong when a kernel module is accessing freed storage. For example, this could result in rgrp corruption because the fake rgrp would point to a fake bitmap in memory too, causing gfs2_inplace_reserve to search some random memory for free blocks, and find some, since we were never setting rgd->rd_bits to NULL before freeing it. This patch fixes the problem by not setting gl_object until we have successfully inserted the rgrp into the rbtree. Also, it sets rd_bits to NULL as it frees them, which will ensure any accidental access to the wrong rgrp will result in a kernel panic rather than file system corruption, which is preferred. Signed-off-by: Bob Peterson <rpeterso@redhat.com>		2016-06-10 07:01:58 -05:00
..
acl.c
acl.h
aops.c
bmap.c
bmap.h
dentry.c
dir.c
dir.h
export.c
file.c
gfs2.h
glock.c
glock.h
glops.c
glops.h
incore.h
inode.c
inode.h
Kconfig
lock_dlm.c
log.c
log.h
lops.c
lops.h
main.c	kmemcg: account certain kmem allocations to memcg	2016-01-14 16:00:49 -08:00
Makefile
meta_io.c
meta_io.h
ops_fstype.c
quota.c
quota.h
recovery.c
recovery.h
rgrp.c	GFS2: don't set rgrp gl_object until it's inserted into rgrp tree	2016-06-10 07:01:58 -05:00
rgrp.h
super.c
super.h
sys.c
sys.h
trace_gfs2.h
trans.c
trans.h
util.c
util.h
xattr.c
xattr.h