summaryrefslogtreecommitdiff
path: root/drivers/char/ipmi/ipmi_msghandler.c
diff options
context:
space:
mode:
authorCorey Minyard <cminyard@mvista.com>2022-04-21 06:49:43 -0500
committerCorey Minyard <cminyard@mvista.com>2022-04-29 10:06:52 -0500
commit9cc3aac42566a0021e0ab7c4e9b31667ad75b1e3 (patch)
treee8d800e687f00f38a47a80d819c6dc1dc2a39946 /drivers/char/ipmi/ipmi_msghandler.c
parent3d092ef09303e615707dc5755cf0e29b4df7555f (diff)
ipmi:ipmi_ipmb: Fix null-ptr-deref in ipmi_unregister_smi()
KASAN report null-ptr-deref as follows: KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:ipmi_unregister_smi+0x7d/0xd50 drivers/char/ipmi/ipmi_msghandler.c:3680 Call Trace: ipmi_ipmb_remove+0x138/0x1a0 drivers/char/ipmi/ipmi_ipmb.c:443 ipmi_ipmb_probe+0x409/0xda1 drivers/char/ipmi/ipmi_ipmb.c:548 i2c_device_probe+0x959/0xac0 drivers/i2c/i2c-core-base.c:563 really_probe+0x3f3/0xa70 drivers/base/dd.c:541 In ipmi_ipmb_probe(), 'iidev->intf' is not set before ipmi_register_smi() success. And in the error handling case, ipmi_ipmb_remove() is called to release resources, ipmi_unregister_smi() is called without check 'iidev->intf', this will cause KASAN null-ptr-deref issue. General kernel style is to allow NULL to be passed into unregister calls, so fix it that way. This allows a NULL check to be removed in other code. Fixes: 57c9e3c9a374 ("ipmi:ipmi_ipmb: Unregister the SMI on remove") Reported-by: Hulk Robot <hulkci@huawei.com> Cc: stable@vger.kernel.org # v5.17+ Cc: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: Corey Minyard <cminyard@mvista.com>
Diffstat (limited to 'drivers/char/ipmi/ipmi_msghandler.c')
-rw-r--r--drivers/char/ipmi/ipmi_msghandler.c5
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index 5f7abf456a17..f1827257ef0e 100644
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -3677,8 +3677,11 @@ static void cleanup_smi_msgs(struct ipmi_smi *intf)
void ipmi_unregister_smi(struct ipmi_smi *intf)
{
struct ipmi_smi_watcher *w;
- int intf_num = intf->intf_num, index;
+ int intf_num, index;
+ if (!intf)
+ return;
+ intf_num = intf->intf_num;
mutex_lock(&ipmi_interfaces_mutex);
intf->intf_num = -1;
intf->in_shutdown = true;