zram: don't call idr_remove() from zram_remove()
authorJerome Marchand <jmarchan@redhat.com>
Sat, 16 Jan 2016 00:54:48 +0000 (16:54 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 19 Feb 2016 22:28:38 +0000 (14:28 -0800)
commitb3143ec6ddea62344574cce2ebf2633eb1958727
treed4115fc8225921cdcb1a8664862a1137a7ea0ae0
parent5b243a2947d98973ba553af9a9b6858d3f59f62f
zram: don't call idr_remove() from zram_remove()

commit 17ec4cd985780a7e30aa45bb8f272237c12502a4 upstream.

The use of idr_remove() is forbidden in the callback functions of
idr_for_each().  It is therefore unsafe to call idr_remove in
zram_remove().

This patch moves the call to idr_remove() from zram_remove() to
hot_remove_store().  In the detroy_devices() path, idrs are removed by
idr_destroy().  This solves an use-after-free detected by KASan.

[akpm@linux-foundation.org: fix coding stype, per Sergey]
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/block/zram/zram_drv.c