In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: fix the crash issue for zero copy XDPTX action
There is a crash issue when running zero copy XDPTX action, the crash log is shown below.
[ 216.122464] Unable to handle kernel paging request at virtual address fffeffff80000000 [ 216.187524] Internal error: Oops: 0000000096000144 [#1] SMP [ 216.301694] Call trace: [ 216.304130] dcachecleanpoc+0x20/0x38 (P) [ 216.308308] dmasyncsinglefordevice+0x1bc/0x1e0 [ 216.313351] stmmacxdpxmitxdpf+0x354/0x400 [ 216.317701] stmmacxdprunprog+0x164/0x368 [ 216.322139] stmmacnapipollrxtx+0xba8/0xf00 [ 216.326576] napipoll+0x40/0x218 [ 216.408054] Kernel panic - not syncing: Oops: Fatal exception in interrupt
For XDPTX action, the xdpbuff is converted to xdpframe by xdpconvertbufftoframe(). The memory type of the resulting xdpframe depends on the memory type of the xdpbuff. For page pool based xdpbuff it produces xdpframe with memory type MEMTYPEPAGEPOOL. For zero copy XSK pool based xdpbuff it produces xdpframe with memory type MEMTYPEPAGEORDER0. However, stmmacxdpxmitback() does not check the memory type and always uses the page pool type, this leads to invalid mappings and causes the crash. Therefore, check the xdpbuff memory type in stmmacxdpxmitback() to fix this issue.
In the Linux kernel, the following vulnerability has been resolved:
NFSD: Fix READDIR buffer overflow
If a client sends a READDIR count argument that is too small (say, zero), then the buffer size calculation in the new initdirlist helper functions results in an underflow, allowing the XDR stream functions to write beyond the actual buffer.
This calculation has always been suspect. NFSD has never sanity- checked the READDIR count argument, but the old entry encoders managed the problem correctly.
With the commits below, entry encoding changed, exposing the underflow to the pointer arithmetic in xdrreservespace().
Modern NFS clients attempt to retrieve as much data as possible for each READDIR request. Also, we have no unit tests that exercise the behavior of READDIR at the lower bound of @count values. Thus this case was missed during testing.
In the Linux kernel, the following vulnerability has been resolved:
net: mana: Fix TOCTOU double-fetch of hwcmsgid from DMA buffer
In manahwcrxeventhandler(), resp->response.hwcmsgid is read from DMA-coherent memory and bounds-checked, then manahwchandleresp() re-reads the same field from the same DMA buffer for testbit() and pointer arithmetic.
DMA-coherent memory is mapped uncacheable on x86 and is shared, unencrypted, in Confidential VMs (SEV-SNP/TDX), so each load goes directly to host-visible memory. A H/W can modify the value between the check and the use, bypassing the bounds validation.
Fix this by reading hwcmsgid exactly once using READONCE() into a stack-local variable in manahwcrxeventhandler(), and passing the validated value as a parameter to manahwchandleresp().
In the Linux kernel, the following vulnerability has been resolved:
net: mana: validate rxreqidx to prevent out-of-bounds array access
In manahwcrxeventhandler(), rxreqidx is derived from sge->address in DMA-coherent memory. In Confidential VMs (SEV-SNP/TDX), this memory is shared unencrypted and HW can modify WQE contents at any time. No bounds check exists on rxreqidx, which can lead to an out-of-bounds access into reqs[].
Add bounds check on rxreqidx in manahwcrxeventhandler() before using it to index the reqs[] array.
In the Linux kernel, the following vulnerability has been resolved:
drm/sched: Avoid data corruptions
Wait for all dependencies of a job to complete before killing it to avoid data corruptions.
In the Linux kernel, the following vulnerability has been resolved:
net, hsr: reject HSR frame if skb can't hold tag
Receiving HSR frame with insufficient space to hold HSR tag in the skb can result in a crash (kernel BUG):
[ 45.390915] skbuff: skbunderpanic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridgeslave1 [ 45.392559] ------------[ cut here ]------------ [ 45.392912] kernel BUG at net/core/skbuff.c:211! [ 45.393276] Oops: invalid opcode: 0000 [#1] SMP DEBUGPAGEALLOC KASAN NOPTI [ 45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 #12 PREEMPT(undef) [ 45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 45.395273] RIP: 0010:skbpanic+0x15b/0x1d0
<snip registers, remove unreliable trace>
[ 45.402911] Call Trace: [ 45.403105] <IRQ> [ 45.404470] skbpush+0xcd/0xf0 [ 45.404726] brdevqueuepushxmit+0x7c/0x6c0 [ 45.406513] brforwardfinish+0x128/0x260 [ 45.408483] brforward+0x42d/0x590 [ 45.409464] maybedeliver+0x2eb/0x420 [ 45.409763] brflood+0x174/0x4a0 [ 45.410030] brhandleframefinish+0xc7c/0x1bc0 [ 45.411618] brhandleframe+0xac3/0x1230 [ 45.413674] netifreceiveskbcore.constprop.0+0x808/0x3df0 [ 45.422966] netifreceiveskbonecore+0xb4/0x1f0 [ 45.424478] netifreceiveskb+0x22/0x170 [ 45.424806] processbacklog+0x242/0x6d0 [ 45.425116] napipoll+0xbb/0x630 [ 45.425394] netrxaction+0x4d1/0xcc0 [ 45.427613] handlesoftirqs+0x1a4/0x580 [ 45.427926] dosoftirq+0x74/0x90 [ 45.428196] </IRQ>
This issue was found by syzkaller.
The panic happens in brdevqueuepushxmit() once it receives a corrupted skb with ETH header already pushed in linear data. When it attempts the skbpush() call, there's not enough headroom and skbpush() panics.
The corrupted skb is put on the queue by HSR layer, which makes a sequence of unintended transformations when it receives a specific corrupted HSR frame (with incomplete TAG).
Fix it by dropping and consuming frames that are not long enough to contain both ethernet and hsr headers.
Alternative fix would be to check for enough headroom before skbpush() in brdevqueuepushxmit().
In the reproducer, this is injected via AFPACKET, but I don't easily see why it couldn't be sent over the wire from adjacent network.
Further Details:
In the reproducer, the following network interface chain is set up:
┌────────────────┐ ┌────────────────┐ │ veth0tohsr ├───┤ hsrslave0 ┼───┐ └────────────────┘ └────────────────┘ │ │ ┌──────┐ ├─┤ hsr0 ├───┐ │ └──────┘ │ ┌────────────────┐ ┌────────────────┐ │ │┌────────┐ │ veth1tohsr ┼───┤ hsrslave1 ├───┘ └┤ │ └────────────────┘ └────────────────┘ ┌┼ bridge │ ││ │ │└────────┘ │ ┌───────┐ │ │ ... ├──────┘ └───────┘
To trigger the events leading up to crash, reproducer sends a corrupted HSR fr ---truncated---
In the Linux kernel, the following vulnerability has been resolved:
ppp: fix race conditions in pppfillforwardpath
pppfillforwardpath() has two race conditions:
1. The ppp->channels list can change between listempty() and listfirstentry(), as ppplock() is not held. If the only channel is deleted in pppdisconnectchannel(), listfirstentry() may access an empty head or a freed entry, and trigger a panic.
2. pch->chan can be NULL. When pppunregisterchannel() is called, pch->chan is set to NULL before pch is removed from ppp->channels.
Fix these by using a lockless RCU approach: - Use listfirstornullrcu() to safely test and access the first list entry. - Convert list modifications on ppp->channels to their RCU variants and add synchronizenet() after removal. - Check for a NULL pch->chan before dereferencing it.
In the Linux kernel, the following vulnerability has been resolved:
net/sched: Fix UAF when resolving a clash
KASAN reports the following UAF:
BUG: KASAN: slab-use-after-free in tcfctflowtableprocessconn+0x12b/0x380 [actct] Read of size 1 at addr ffff888c07603600 by task handler130/6469
Call Trace: <IRQ> dumpstacklvl+0x48/0x70 printaddressdescription.constprop.0+0x33/0x3d0 printreport+0xc0/0x2b0 kasanreport+0xd0/0x120 asanload1+0x6c/0x80 tcfctflowtableprocessconn+0x12b/0x380 [actct] tcfctact+0x886/0x1350 [actct] tcfactionexec+0xf8/0x1f0 flclassify+0x355/0x360 [clsflower] tcfclassify+0x1fd/0x330 tcfclassify+0x21c/0x3c0 schhandleingress.constprop.0+0x2c5/0x500 netifreceiveskbcore.constprop.0+0xb25/0x1510 netifreceiveskblistcore+0x220/0x4c0 netifreceiveskblistinternal+0x446/0x620 napicompletedone+0x157/0x3d0 grocellpoll+0xcf/0x100 napipoll+0x65/0x310 netrxaction+0x30c/0x5c0 dosoftirq+0x14f/0x491 irqexitrcu+0x82/0xc0 irqexitrcu+0xe/0x20 commoninterrupt+0xa1/0xb0 </IRQ> <TASK> asmcommoninterrupt+0x27/0x40
Allocated by task 6469: kasansavestack+0x38/0x70 kasansettrack+0x25/0x40 kasansaveallocinfo+0x1e/0x40 kasankrealloc+0x133/0x190 krealloc+0xaa/0x130 nfctextadd+0xed/0x230 [nfconntrack] tcfctact+0x1095/0x1350 [actct] tcfactionexec+0xf8/0x1f0 flclassify+0x355/0x360 [clsflower] tcfclassify+0x1fd/0x330 tcfclassify+0x21c/0x3c0 schhandleingress.constprop.0+0x2c5/0x500 netifreceiveskbcore.constprop.0+0xb25/0x1510 netifreceiveskblistcore+0x220/0x4c0 netifreceiveskblistinternal+0x446/0x620 napicompletedone+0x157/0x3d0 grocellpoll+0xcf/0x100 napipoll+0x65/0x310 netrxaction+0x30c/0x5c0 dosoftirq+0x14f/0x491
Freed by task 6469: kasansavestack+0x38/0x70 kasansettrack+0x25/0x40 kasansavefreeinfo+0x2b/0x60 kasanslabfree+0x180/0x1f0 kasanslabfree+0x12/0x30 slabfreefreelisthook+0xd2/0x1a0 kmemcachefree+0x1a2/0x2f0 kfree+0x78/0x120 nfconntrackfree+0x74/0x130 [nfconntrack] nfctdestroy+0xb2/0x140 [nfconntrack] nfctresolveclash+0x529/0x5d0 [nfconntrack] nfctresolveclash+0xf6/0x490 [nfconntrack] nfconntrackconfirm+0x2c6/0x770 [nfconntrack] tcfctact+0x12ad/0x1350 [actct] tcfactionexec+0xf8/0x1f0 flclassify+0x355/0x360 [clsflower] tcfclassify+0x1fd/0x330 tcfclassify+0x21c/0x3c0 schhandleingress.constprop.0+0x2c5/0x500 netifreceiveskbcore.constprop.0+0xb25/0x1510 netifreceiveskblistcore+0x220/0x4c0 netifreceiveskblistinternal+0x446/0x620 napicompletedone+0x157/0x3d0 grocellpoll+0xcf/0x100 napipoll+0x65/0x310 netrxaction+0x30c/0x5c0 dosoftirq+0x14f/0x491
The ct may be dropped if a clash has been resolved but is still passed to the tcfctflowtableprocessconn function for further usage. This issue can be fixed by retrieving ct from skb again after confirming conntrack.
igc: avoid returning frame twice in XDPREDIRECT
In the Linux kernel, the following vulnerability has been resolved:
scsi: iscsi: Fix conn use after free during resets
If we haven't done a unbind target call we can race where iscsiconnteardown wakes up the EH thread and then frees the conn while those threads are still accessing the conn ehwait.
We can only do one TMF per session so this just moves the TMF fields from the conn to the session. We can then rely on the iscsisessionteardown->iscsiremovesession->iscsiunbindsession call to remove the target and it's devices, and know after that point there is no device or scsi-ml callout trying to access the session.
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: kTLS, Fix crash in RX resync flow
For the TLS RX resync flow, we maintain a list of TLS contexts that require some attention, to communicate their resync information to the HW. Here we fix list corruptions, by protecting the entries against movements coming from resynchandleseqmatch(), until their resync handling in napi is fully completed.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Avoid HDCP over-read and corruption
Instead of reading the desired 5 bytes of the actual target field, the code was reading 8. This could result in a corrupted value if the trailing 3 bytes were non-zero, so instead use an appropriately sized and zero-initialized bounce buffer, and read only 5 bytes before casting to u64.
Last updated 24 July 2024