| From 7455b7007b9e93bcc2bc9c1c6c73a228e3152069 Mon Sep 17 00:00:00 2001 |
| From: Conor Dooley <conor.dooley@microchip.com> |
| Date: Thu, 13 Apr 2023 23:20:45 +0100 |
| Subject: clk: microchip: fix potential UAF in auxdev release callback |
| |
| From: Conor Dooley <conor.dooley@microchip.com> |
| |
| commit 7455b7007b9e93bcc2bc9c1c6c73a228e3152069 upstream. |
| |
| Similar to commit 1c11289b34ab ("peci: cpu: Fix use-after-free in |
| adev_release()"), the auxiliary device is not torn down in the correct |
| order. If auxiliary_device_add() fails, the release callback will be |
| called twice, resulting in a UAF. Due to timing, the auxdev code in this |
| driver "took inspiration" from the aforementioned commit, and thus its |
| bugs too! |
| |
| Moving auxiliary_device_uninit() to the unregister callback instead |
| avoids the issue. |
| |
| CC: stable@vger.kernel.org |
| Fixes: b56bae2dd6fd ("clk: microchip: mpfs: add reset controller") |
| Signed-off-by: Conor Dooley <conor.dooley@microchip.com> |
| Link: https://lore.kernel.org/r/20230413-critter-synopsis-dac070a86cb4@spud |
| Signed-off-by: Stephen Boyd <sboyd@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/clk/microchip/clk-mpfs.c | 3 +-- |
| 1 file changed, 1 insertion(+), 2 deletions(-) |
| |
| --- a/drivers/clk/microchip/clk-mpfs.c |
| +++ b/drivers/clk/microchip/clk-mpfs.c |
| @@ -374,14 +374,13 @@ static void mpfs_reset_unregister_adev(v |
| struct auxiliary_device *adev = _adev; |
| |
| auxiliary_device_delete(adev); |
| + auxiliary_device_uninit(adev); |
| } |
| |
| static void mpfs_reset_adev_release(struct device *dev) |
| { |
| struct auxiliary_device *adev = to_auxiliary_dev(dev); |
| |
| - auxiliary_device_uninit(adev); |
| - |
| kfree(adev); |
| } |
| |
