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:
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:
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.
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 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 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'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 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/
The tcpmssmanglepacket function in net/netfilter/xtTCPMSS.c in the Linux kernel before 4.11, and 4.9.x before 4.9.36, allows remote attackers to cause a denial of service (use-after-free and memory corruption) or possibly have unspecified other impact by leveraging the presence of xtTCPMSS in an iptables action.
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.
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
Last updated 24 July 2024