[PATCH 4.14 161/195] ipmi: use dynamic memory for DMI driver override
From: Greg Kroah-Hartman
Date: Thu Feb 15 2018 - 10:38:17 EST
4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: John Garry <john.garry@xxxxxxxxxx>
commit 5516e21a1e95e9b9f39985598431a25477d91643 upstream.
Currently a crash can be seen if we reach the "err"
label in dmi_add_platform_ipmi(), calling
platform_device_put(), like here:
[ 7.270584] (null): ipmi:dmi: Unable to add resources: -16
[ 7.330229] ------------[ cut here ]------------
[ 7.334889] kernel BUG at mm/slub.c:3894!
[ 7.338936] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[ 7.344475] Modules linked in:
[ 7.347556] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.15.0-rc2-00004-gbe9cb7b-dirty #114
[ 7.355907] Hardware name: Huawei Taishan 2280 /D05, BIOS Hisilicon D05 IT17 Nemo 2.0 RC0 11/29/2017
[ 7.365137] task: 00000000c211f6d3 task.stack: 00000000f276e9af
[ 7.371116] pstate: 60000005 (nZCv daif -PAN -UAO)
[ 7.375957] pc : kfree+0x194/0x1b4
[ 7.379389] lr : platform_device_release+0xcc/0xd8
[ 7.384225] sp : ffff0000092dba90
[ 7.387567] x29: ffff0000092dba90 x28: ffff000008a83000
[ 7.392933] x27: ffff0000092dbc10 x26: 00000000000000e6
[ 7.398297] x25: 0000000000000003 x24: ffff0000085b51e8
[ 7.403662] x23: 0000000000000100 x22: ffff7e0000234cc0
[ 7.409027] x21: ffff000008af3660 x20: ffff8017d21acc10
[ 7.414392] x19: ffff8017d21acc00 x18: 0000000000000002
[ 7.419757] x17: 0000000000000001 x16: 0000000000000008
[ 7.425121] x15: 0000000000000001 x14: 6666666678303d65
[ 7.430486] x13: 6469727265766f5f x12: 7265766972642e76
[ 7.435850] x11: 6564703e2d617020 x10: 6530326435373638
[ 7.441215] x9 : 3030303030303030 x8 : 3d76656420657361
[ 7.446580] x7 : ffff000008f59df8 x6 : ffff8017fbe0ea50
[ 7.451945] x5 : 0000000000000000 x4 : 0000000000000000
[ 7.457309] x3 : ffffffffffffffff x2 : 0000000000000000
[ 7.462674] x1 : 0fffc00000000800 x0 : ffff7e0000234ce0
[ 7.468039] Process swapper/0 (pid: 1, stack limit = 0x00000000f276e9af)
[ 7.474809] Call trace:
[ 7.477272] kfree+0x194/0x1b4
[ 7.480351] platform_device_release+0xcc/0xd8
[ 7.484837] device_release+0x34/0x90
[ 7.488531] kobject_put+0x70/0xcc
[ 7.491961] put_device+0x14/0x1c
[ 7.495304] platform_device_put+0x14/0x1c
[ 7.499439] dmi_add_platform_ipmi+0x348/0x3ac
[ 7.503923] scan_for_dmi_ipmi+0xfc/0x10c
[ 7.507970] do_one_initcall+0x38/0x124
[ 7.511840] kernel_init_freeable+0x188/0x228
[ 7.516238] kernel_init+0x10/0x100
[ 7.519756] ret_from_fork+0x10/0x18
[ 7.523362] Code: f94002c0 37780080 f94012c0 37000040 (d4210000)
[ 7.529552] ---[ end trace 11750e4787deef9e ]---
[ 7.534228] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
[ 7.534228]
This is because when the device is released in
platform_device_release(), we try to free
pdev.driver_override. This is a const string, hence
the crash.
Fix by using dynamic memory for pdev->driver_override.
Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
[Removed the free of driver_override from ipmi_si_remove_by_dev(). The
free is done in platform_device_release(), and would result in a double
free, and ipmi_si_remove_by_dev() is called by non-platform devices.]
Signed-off-by: Corey Minyard <cminyard@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/char/ipmi/ipmi_dmi.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/drivers/char/ipmi/ipmi_dmi.c
+++ b/drivers/char/ipmi/ipmi_dmi.c
@@ -81,7 +81,10 @@ static void __init dmi_add_platform_ipmi
pr_err("ipmi:dmi: Error allocation IPMI platform device");
return;
}
- pdev->driver_override = override;
+ pdev->driver_override = kasprintf(GFP_KERNEL, "%s",
+ override);
+ if (!pdev->driver_override)
+ goto err;
if (type == IPMI_DMI_TYPE_SSIF)
goto add_properties;