CVE-2024-36928: s390/qeth: Fix kernel panic after setting hsuid
In the Linux kernel, the following vulnerability has been resolved:
s390/qeth: Fix kernel panic after setting hsuid
Symptom: When the hsuid attribute is set for the first time on an IQD Layer3 device while the corresponding network interface is already UP, the kernel will try to execute a napi function pointer that is NULL.
Example: --------------------------------------------------------------------------- [ 2057.572696] illegal operation: 0001 ilc:1 [#1] SMP [ 2057.572702] Modules linked in: afiucv qethl3 zfcp scsitransportfc sunrpc nftfibinet nftfibipv4 nftfibipv6 nftfib nftrejectinet nfrejectipv4 nfrejectipv6 nftreject nftct nftablesset nftchainnat nfnat nfconntrack nfdefragipv6 nfdefragipv4 ipset nftables libcrc32c nfnetlink ghashs390 prng xts aess390 dess390 de sgeneric sha3512s390 sha3256s390 sha512s390 vfioccw vfiomdev mdev vfioiommutype1 eadmsch vfio ext4 mbcache jbd2 qethl2 bridge stp llc dasdeckdmod qeth dasdmod qdio ccwgroup pkey zcrypt [ 2057.572739] CPU: 6 PID: 60182 Comm: stressclient Kdump: loaded Not tainted 4.18.0-541.el8.s390x #1 [ 2057.572742] Hardware name: IBM 3931 A01 704 (LPAR) [ 2057.572744] Krnl PSW : 0704f00180000000 0000000000000002 (0x2) [ 2057.572748] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3 [ 2057.572751] Krnl GPRS: 0000000000000004 0000000000000000 00000000a3b008d8 0000000000000000 [ 2057.572754] 00000000a3b008d8 cb923a29c779abc5 0000000000000000 00000000814cfd80 [ 2057.572756] 000000000000012c 0000000000000000 00000000a3b008d8 00000000a3b008d8 [ 2057.572758] 00000000bab6d500 00000000814cfd80 0000000091317e46 00000000814cfc68 [ 2057.572762] Krnl Code:#0000000000000000: 0000 illegal >0000000000000002: 0000 illegal 0000000000000004: 0000 illegal 0000000000000006: 0000 illegal 0000000000000008: 0000 illegal 000000000000000a: 0000 illegal 000000000000000c: 0000 illegal 000000000000000e: 0000 illegal [ 2057.572800] Call Trace: [ 2057.572801] ([<00000000ec639700>] 0xec639700) [ 2057.572803] [<00000000913183e2>] netrxaction+0x2ba/0x398 [ 2057.572809] [<0000000091515f76>] dosoftirq+0x11e/0x3a0 [ 2057.572813] [<0000000090ce160c>] dosoftirqownstack+0x3c/0x58 [ 2057.572817] ([<0000000090d2cbd6>] dosoftirq.part.1+0x56/0x60) [ 2057.572822] [<0000000090d2cc60>] localbhenableip+0x80/0x98 [ 2057.572825] [<0000000091314706>] devqueuexmit+0x2be/0xd70 [ 2057.572827] [<000003ff803dd6d6>] afiucvhssend+0x24e/0x300 [afiucv] [ 2057.572830] [<000003ff803dd88a>] iucvsendctrl+0x102/0x138 [afiucv] [ 2057.572833] [<000003ff803de72a>] iucvsockconnect+0x37a/0x468 [afiucv] [ 2057.572835] [<00000000912e7e90>] sysconnect+0xa0/0xd8 [ 2057.572839] [<00000000912e9580>] syssocketcall+0x228/0x348 [ 2057.572841] [<0000000091514e1a>] systemcall+0x2a6/0x2c8 [ 2057.572843] Last Breaking-Event-Address: [ 2057.572844] [<0000000091317e44>] napipoll+0x4c/0x1d8 [ 2057.572846] [ 2057.572847] Kernel panic - not syncing: Fatal exception in interrupt -------------------------------------------------------------------------------------------
Analysis: There is one napi structure per outq: card->qdio.outqs[i].napi The napi.poll functions are set during qethopen().
Since commit 1cfef80d4c2b ("s390/qeth: Don't call devclose/devopen (DOWN/UP)") qethsetoffline()/qethsetonline() no longer call devclose()/ devopen(). So if qethfreeqdioqueues() cleared card->qdio.outqs[i].napi.poll while the network interface was UP and the card was offline, they are not set again.
Reproduction: chzdev -e $devno layer2=0 ip link set dev $networkinterface up echo 0 > /sys/bus/ccw ---truncated---
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.25-1Fixed in 6.12.27-1 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch 1cfef80d4c2b - Compensating control
Avoid the triggering sequence: do not set the hsuid attribute for the first time on an IQD Layer3 device while the corresponding network interface is already UP (i.e., avoid bringing the interface up before setting hsuid).
Event History
Frequently Asked Questions
What is the severity of CVE-2024-36928?
CVE-2024-36928 has a severity rating that indicates it can cause kernel panic under specific conditions.
How do I fix CVE-2024-36928?
To fix CVE-2024-36928, update to the latest kernel versions as specified, such as 6.1.123-1, 6.1.128-1, or 6.12.12-1.
Which Linux kernel versions are affected by CVE-2024-36928?
Affected Linux kernel versions include those up to 5.10.226-1.
What are the symptoms of CVE-2024-36928?
The primary symptom of CVE-2024-36928 is a kernel panic occurring after setting the hsuid attribute on an IQD Layer3 device.
Is there a patch available for CVE-2024-36928?
Yes, kernel patches addressing CVE-2024-36928 are included in the newer releases of the kernel.