CVE-2022-50356: net: sched: sfb: fix null pointer access issue when sfb_init() fails
In the Linux kernel, the following vulnerability has been resolved:
net: sched: sfb: fix null pointer access issue when sfbinit() fails
When the default qdisc is sfb, if the qdisc of devqueue fails to be inited during mqprioinit(), sfbreset() is invoked to clear resources. In this case, the q->qdisc is NULL, and it will cause gpf issue.
The process is as follows: qdisccreatedflt() sfbinit() tcfblockget() --->failed, q->qdisc is NULL ... qdiscput() ... sfbreset() qdiscreset(q->qdisc) --->q->qdisc is NULL ops = qdisc->ops
The following is the Call Trace information: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] RIP: 0010:qdiscreset+0x2b/0x6f0 Call Trace: <TASK> sfbreset+0x37/0xd0 qdiscreset+0xed/0x6f0 qdiscdestroy+0x82/0x4c0 qdiscput+0x9e/0xb0 qdisccreatedflt+0x2c3/0x4a0 mqprioinit+0xa71/0x1760 qdisccreate+0x3eb/0x1000 tcmodifyqdisc+0x408/0x1720 rtnetlinkrcvmsg+0x38e/0xac0 netlinkrcvskb+0x12d/0x3a0 netlinkunicast+0x4a2/0x740 netlinksendmsg+0x826/0xcc0 socksendmsg+0xc5/0x100 syssendmsg+0x583/0x690 syssendmsg+0xe8/0x160 syssendmsg+0xbf/0x160 dosyscall64+0x35/0x80 entrySYSCALL64afterhwframe+0x46/0xb0 RIP: 0033:0x7f2164122d04 </TASK>
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2022-50356?
CVE-2022-50356 has a severity rating of medium due to potential null pointer dereference in the Linux kernel.
How do I fix CVE-2022-50356?
To fix CVE-2022-50356, update your Linux kernel to the latest stable version that includes the patch addressing this vulnerability.
Who is affected by CVE-2022-50356?
CVE-2022-50356 affects users and systems running versions of the Linux kernel that utilize the sfb queuing discipline.
What is the impact of CVE-2022-50356?
The impact of CVE-2022-50356 can result in potential system instability or crashes due to null pointer access issues in the scheduling function.
When was CVE-2022-50356 published?
CVE-2022-50356 was published in the year 2022 as part of the ongoing security updates for the Linux kernel.