clk: Fix double free due to devm_clk_register()
authorStephen Boyd <sboyd@codeaurora.org>
Fri, 18 Apr 2014 23:29:42 +0000 (16:29 -0700)
committerMike Turquette <mturquette@linaro.org>
Wed, 30 Apr 2014 18:44:04 +0000 (11:44 -0700)
commit293ba3b4a4fd54891b900f2911d1a57e1ed4a843
tree3f789807e81edf9fec502a2cd766dcf8dc95c247
parent2aa6dd07bd86daf4dd7ddb3118dd2d0941fbda2e
clk: Fix double free due to devm_clk_register()

Now that clk_unregister() frees the struct clk we're
unregistering we'll free memory twice: first we'll call kfree()
in __clk_release() with an address kmalloc doesn't know about and
second we'll call kfree() in the devres layer. Remove the
allocation of struct clk in devm_clk_register() and let
clk_release() handle it. This fixes slab errors like:

=============================================================================
BUG kmalloc-128 (Not tainted): Invalid object pointer 0xed08e8d0
-----------------------------------------------------------------------------

Disabling lock debugging due to kernel taint
INFO: Slab 0xeec503f8 objects=25 used=15 fp=0xed08ea00 flags=0x4081
CPU: 2 PID: 73 Comm: rmmod Tainted: G    B         3.14.0-11032-g526e9c764381 #34
[<c0014be0>] (unwind_backtrace) from [<c0012240>] (show_stack+0x10/0x14)
[<c0012240>] (show_stack) from [<c04b74dc>] (dump_stack+0x70/0xbc)
[<c04b74dc>] (dump_stack) from [<c00f6778>] (slab_err+0x74/0x84)
[<c00f6778>] (slab_err) from [<c04b6278>] (free_debug_processing+0x2cc/0x31c)
[<c04b6278>] (free_debug_processing) from [<c04b6300>] (__slab_free+0x38/0x41c)
[<c04b6300>] (__slab_free) from [<c03931bc>] (clk_unregister+0xd4/0x140)
[<c03931bc>] (clk_unregister) from [<c02fb774>] (release_nodes+0x164/0x1d8)
[<c02fb774>] (release_nodes) from [<c02f8698>] (__device_release_driver+0x60/0xb0)
[<c02f8698>] (__device_release_driver) from [<c02f9080>] (driver_detach+0xb4/0xb8)
[<c02f9080>] (driver_detach) from [<c02f8480>] (bus_remove_driver+0x5c/0xc4)
[<c02f8480>] (bus_remove_driver) from [<c008c9b8>] (SyS_delete_module+0x148/0x1d8)
[<c008c9b8>] (SyS_delete_module) from [<c000ef80>] (ret_fast_syscall+0x0/0x48)
FIX kmalloc-128: Object at 0xed08e8d0 not freed

Fixes: fcb0ee6a3d33 (clk: Implement clk_unregister)
Cc: Jiada Wang <jiada_wang@mentor.com>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Cc: stable@vger.kernel.org
drivers/clk/clk.c