In the Linux kernel, the following vulnerability has been resolved:
drbd: add missing krefget in handlewriteconflicts
With two-primaries enabled, DRBD tries to detect "concurrent" writes and handle write conflicts, so that even if you write to the same sector simultaneously on both nodes, they end up with the identical data once the writes are completed.
In handling "superseeded" writes, we forgot a krefget, resulting in a premature drbddestroydevice and use after free, and further to kernel crashes with symptoms.
Relevance: No one should use DRBD as a random data generator, and apparently all users of "two-primaries" handle concurrent writes correctly on layer up. That is cluster file systems use some distributed lock manager, and live migration in virtualization environments stops writes on one node before starting writes on the other node.
Which means that other than for "test cases", this code path is never taken in real life.
FYI, in DRBD 9, things are handled differently nowadays. We still detect "write conflicts", but no longer try to be smart about them. We decided to disconnect hard instead: upper layers must not submit concurrent writes. If they do, that's their fault.
In the Linux kernel, the following vulnerability has been resolved:
net: systemport: Add global locking for descriptor lifecycle
The descriptor list is a shared resource across all of the transmit queues, and the locking mechanism used today only protects concurrency across a given transmit queue between the transmit and reclaiming. This creates an opportunity for the SYSTEMPORT hardware to work on corrupted descriptors if we have multiple producers at once which is the case when using multiple transmit queues.
This was particularly noticeable when using multiple flows/transmit queues and it showed up in interesting ways in that UDP packets would get a correct UDP header checksum being calculated over an incorrect packet length. Similarly TCP packets would get an equally correct checksum computed by the hardware over an incorrect packet length.
The SYSTEMPORT hardware maintains an internal descriptor list that it re-arranges when the driver produces a new descriptor anytime it writes to the WRITEPORT{HI,LO} registers, there is however some delay in the hardware to re-organize its descriptors and it is possible that concurrent TX queues eventually break this internal allocation scheme to the point where the length/status part of the descriptor gets used for an incorrect data buffer.
The fix is to impose a global serialization for all TX queues in the short section where we are writing to the WRITEPORT{HI,LO} registers which solves the corruption even with multiple concurrent TX queues being used.
In the Linux kernel, the following vulnerability has been resolved:
nfsd: fix use-after-free due to delegation race
A delegation break could arrive as soon as we've called vfssetlease. A delegation break runs a callback which immediately (in nfsd4cbrecallprepare) adds the delegation to delrecalllru. If we then exit nfs4setdelegation without hashing the delegation, it will be freed as soon as the callback is done with it, without ever being removed from delrecalllru.
Symptoms show up later as use-after-free or list corruption warnings, usually in the laundromat thread.
I suspect aba2072f4523 "nfsd: grant read delegations to clients holding writes" made this bug easier to hit, but I looked as far back as v3.0 and it looks to me it already had the same problem. So I'm not sure where the bug was introduced; it may have been there from the beginning.
In the Linux kernel, the following vulnerability has been resolved:
isofs: Fix out of bound access for corrupted isofs image
When isofs image is suitably corrupted isofsreadinode() can read data beyond the end of buffer. Sanity-check the directory entry length before using it.
In the Linux kernel, the following vulnerability has been resolved:
NFS: fix an incorrect limit in filelayoutdecodelayout()
The "sizeof(struct nfsfh)" is two bytes too large and could lead to memory corruption. It should be NFSMAXFHSIZE because that's the size of the ->data[] buffer.
I reversed the size of the arguments to put the variable on the left.
In the Linux kernel, the following vulnerability has been resolved:
tipc: skblinearize the head skb when reassembling msgs
It's not a good idea to append the frag skb to a skb's fraglist if the fraglist already has skbs from elsewhere, such as this skb was created by pskbcopy() where the fraglist was cloned (all the skbs in it were skbget'ed) and shared by multiple skbs.
However, the new appended frag skb should have been only seen by the current skb. Otherwise, it will cause use after free crashes as this appended frag skb are seen by multiple skbs but it only got skbget called once.
The same thing happens with a skb updated by pskbmaypull() with a skbcloned skb. Li Shuang has reported quite a few crashes caused by this when doing testing over macvlan devices:
[] kernel BUG at net/core/skbuff.c:1970! [] Call Trace: [] skbclone+0x4d/0xb0 [] macvlanbroadcast+0xd8/0x160 [macvlan] [] macvlanprocessbroadcast+0x148/0x150 [macvlan] [] processonework+0x1a7/0x360 [] workerthread+0x30/0x390
[] kernel BUG at mm/usercopy.c:102! [] Call Trace: [] checkheapobject+0xd3/0x100 [] checkobjectsize+0xff/0x16b [] simplecopytoiter+0x1c/0x30 [] skbdatagramiter+0x7d/0x310 [] skbdatagramiter+0x2a5/0x310 [] skbcopydatagramiter+0x3b/0x90 [] tipcrecvmsg+0x14a/0x3a0 [tipc] [] sysrecvmsg+0x91/0x150 [] sysrecvmsg+0x7b/0xc0
[] kernel BUG at mm/slub.c:305! [] Call Trace: [] <IRQ> [] kmemcachefree+0x3ff/0x400 [] netifreceiveskbcore+0x12c/0xc40 [] ? kmemcachealloc+0x12e/0x270 [] netifreceiveskbinternal+0x3d/0xb0 [] ? getrxpageinfo+0x8e/0xa0 [be2net] [] bepoll+0x6ef/0xd00 [be2net] [] ? irqexit+0x4f/0x100 [] netrxaction+0x149/0x3b0
...
This patch is to fix it by linearizing the head skb if it has fraglist set in tipcbufappend(). Note that we choose to do this before calling skbunshare(), as skblinearize() will avoid skbcopy(). Also, we can not just drop the fraglist either as the early time.
An issue was found in the Linux kernel ipv6 implementation of GRE tunnels which allows a remote attacker to trigger an out-of-bounds access. At this time we understand no trust barrier has been crossed and there is no security implications in this flaw.
References:
http://seclists.org/oss-sec/2017/q1/323
Upstream patch:
https://git.kernel.org/cgit/linux/kernel/git/davem/net.git/commit/?id=7892032cfe67f4bde6fc2ee967e45a8fbaf33756
A vulnerability was found in the Linux kernel's generic WiFi ESSID handling implementation. The flaw allows a system to join a wireless network where the ESSID is longer than the maximum length of 32 characters, which can cause the system to crash or execute code.
A flaw in the Linux kernel's WiFi beacon validation code was discovered. The code does not check the length of the variable length elements in the beacon head potentially leading to a buffer overflow. System availability, as well as data confidentiality and integrity, can be impacted by this vulnerability.
An issue was discovered in the Linux kernel before 5.2.3. Out of bounds access exists in the functions ath6klwmipstreamtimeouteventrx and ath6klwmicaceventrx in the file drivers/net/wireless/ath/ath6kl/wmi.c.
A flaw was found in the Linux kernel's Marvell wifi chip driver. A heap overflow in mwifiexprocesstdlsactionframe function in marvell/mwifiex/tdls.c allows remote attackers to cause a denial of service(system crash) or execute arbitrary code. the station receive a tdls setup request or respone frame which the EIDSUPPRATES IE 's length is larger than 32 will cause Heap Overflow.
A heap-based buffer overflow vulnerability was found in the Linux kernel, version kernel-2.6.32, in Marvell WiFi chip driver. A remote attacker could cause a denial of service (system crash) or, possibly execute arbitrary code, when the lbsibssjoinexisting function is called after a STA connects to an AP.
A stack-based buffer overflow was found in the Linux kernel, version kernel-2.6.32, in Marvell WiFi chip driver. An attacker is able to cause a denial of service (system crash) or, possibly execute arbitrary code, when a STA works in IBSS mode (allows connecting stations together without the use of an AP) and connects to another STA.
A heap-based buffer overflow was discovered in the Linux kernel, all versions 3.x.x and 4.x.x before 4.18.0, in Marvell WiFi chip driver. The flaw could occur when the station attempts a connection negotiation during the handling of the remote devices country settings. This could allow the remote device to cause a denial of service (system crash) or possibly execute arbitrary code.
A flaw was found in the Linux kernel. A heap based buffer overflow in mwifiexuapparsetailies function in drivers/net/wireless/marvell/mwifiex/ie.c might lead to memory corruption and possibly other consequences.
In the Linux kernel before 4.16.4, a double free vulnerability in the fmidisetalt function of drivers/usb/gadget/function/fmidi.c in the fmidi driver may allow attackers to cause a denial of service or possibly have unspecified other impact.
Last updated 4 July 2026
In /drivers/isdn/i4l/isdnnet.c: A user-controlled buffer is copied into a local buffer of constant size using strcpy without a length check which can cause a buffer overflow. This affects the Linux kernel 4.9-stable tree, 4.12-stable tree, 3.18-stable tree, and 4.4-stable tree.
Last updated 24 July 2024
A flaw was found in the Linux kernels implementation of seqfile where an local attacker could create a situation in which an attacker could manipulate memory in which the function pointer to put() could be used for malicious purposes. This could lead to memory corruption and possible privledged escalation.
There are no exploits available for this flaw at this time.
Upstream patch:
https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=77da160530dd1dc94f6ae15a981f24e5f0021e84
A vulnerability was found in technisatusb2getir in drivers/media/usb/dvb-usb/technisat-usb2.c in DVB USB subsystem, there was an out-of-bounds read for an array in struct technisatusb2state state->buf with no boundary check applied until 0xff byte is encountered, if it is not found with in the limits it goes beyond the array size, this exposes kernel data structure which should not happen.
Reference: https://lore.kernel.org/linux-media/20190821104408.w7krumcglxo6fz5q@gofer.mess.org/ https://git.linuxtv.org/mediatree.git/commit/?id=0c4df39e504bf925ab666132ac3c98d6cbbe380b https://lore.kernel.org/lkml/b9b256cb-95f2-5fa1-9956-5a602a017c11@gmail.com/
Use-after-free vulnerability in the ffsusercopyworker function in drivers/usb/gadget/function/ffs.c in the Linux kernel before 4.5.3 allows local users to gain privileges by accessing an I/O data structure after a certain callback call.
Race condition in the ionioctl function in drivers/staging/android/ion/ion.c in the Linux kernel before 4.6 allows local users to gain privileges or cause a denial of service (use-after-free) by calling IONIOCFREE on two CPUs at the same time.