| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Forget ranges when refining tnum after JSET
Syzbot reported a kernel warning due to a range invariant violation on
the following BPF program.
0: call bpf_get_netns_cookie
1: if r0 == 0 goto <exit>
2: if r0 & Oxffffffff goto <exit>
The issue is on the path where we fall through both jumps.
That path is unreachable at runtime: after insn 1, we know r0 != 0, but
with the sign extension on the jset, we would only fallthrough insn 2
if r0 == 0. Unfortunately, is_branch_taken() isn't currently able to
figure this out, so the verifier walks all branches. The verifier then
refines the register bounds using the second condition and we end
up with inconsistent bounds on this unreachable path:
1: if r0 == 0 goto <exit>
r0: u64=[0x1, 0xffffffffffffffff] var_off=(0, 0xffffffffffffffff)
2: if r0 & 0xffffffff goto <exit>
r0 before reg_bounds_sync: u64=[0x1, 0xffffffffffffffff] var_off=(0, 0)
r0 after reg_bounds_sync: u64=[0x1, 0] var_off=(0, 0)
Improving the range refinement for JSET to cover all cases is tricky. We
also don't expect many users to rely on JSET given LLVM doesn't generate
those instructions. So instead of improving the range refinement for
JSETs, Eduard suggested we forget the ranges whenever we're narrowing
tnums after a JSET. This patch implements that approach. |
| In the Linux kernel, the following vulnerability has been resolved:
nvme: nvme-fc: Ensure ->ioerr_work is cancelled in nvme_fc_delete_ctrl()
nvme_fc_delete_assocation() waits for pending I/O to complete before
returning, and an error can cause ->ioerr_work to be queued after
cancel_work_sync() had been called. Move the call to cancel_work_sync() to
be after nvme_fc_delete_association() to ensure ->ioerr_work is not running
when the nvme_fc_ctrl object is freed. Otherwise the following can occur:
[ 1135.911754] list_del corruption, ff2d24c8093f31f8->next is NULL
[ 1135.917705] ------------[ cut here ]------------
[ 1135.922336] kernel BUG at lib/list_debug.c:52!
[ 1135.926784] Oops: invalid opcode: 0000 [#1] SMP NOPTI
[ 1135.931851] CPU: 48 UID: 0 PID: 726 Comm: kworker/u449:23 Kdump: loaded Not tainted 6.12.0 #1 PREEMPT(voluntary)
[ 1135.943490] Hardware name: Dell Inc. PowerEdge R660/0HGTK9, BIOS 2.5.4 01/16/2025
[ 1135.950969] Workqueue: 0x0 (nvme-wq)
[ 1135.954673] RIP: 0010:__list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1135.961041] Code: c7 c7 98 68 72 94 e8 26 45 fe ff 0f 0b 48 c7 c7 70 68 72 94 e8 18 45 fe ff 0f 0b 48 89 fe 48 c7 c7 80 69 72 94 e8 07 45 fe ff <0f> 0b 48 89 d1 48 c7 c7 a0 6a 72 94 48 89 c2 e8 f3 44 fe ff 0f 0b
[ 1135.979788] RSP: 0018:ff579b19482d3e50 EFLAGS: 00010046
[ 1135.985015] RAX: 0000000000000033 RBX: ff2d24c8093f31f0 RCX: 0000000000000000
[ 1135.992148] RDX: 0000000000000000 RSI: ff2d24d6bfa1d0c0 RDI: ff2d24d6bfa1d0c0
[ 1135.999278] RBP: ff2d24c8093f31f8 R08: 0000000000000000 R09: ffffffff951e2b08
[ 1136.006413] R10: ffffffff95122ac8 R11: 0000000000000003 R12: ff2d24c78697c100
[ 1136.013546] R13: fffffffffffffff8 R14: 0000000000000000 R15: ff2d24c78697c0c0
[ 1136.020677] FS: 0000000000000000(0000) GS:ff2d24d6bfa00000(0000) knlGS:0000000000000000
[ 1136.028765] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1136.034510] CR2: 00007fd207f90b80 CR3: 000000163ea22003 CR4: 0000000000f73ef0
[ 1136.041641] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1136.048776] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[ 1136.055910] PKRU: 55555554
[ 1136.058623] Call Trace:
[ 1136.061074] <TASK>
[ 1136.063179] ? show_trace_log_lvl+0x1b0/0x2f0
[ 1136.067540] ? show_trace_log_lvl+0x1b0/0x2f0
[ 1136.071898] ? move_linked_works+0x4a/0xa0
[ 1136.075998] ? __list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1136.081744] ? __die_body.cold+0x8/0x12
[ 1136.085584] ? die+0x2e/0x50
[ 1136.088469] ? do_trap+0xca/0x110
[ 1136.091789] ? do_error_trap+0x65/0x80
[ 1136.095543] ? __list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1136.101289] ? exc_invalid_op+0x50/0x70
[ 1136.105127] ? __list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1136.110874] ? asm_exc_invalid_op+0x1a/0x20
[ 1136.115059] ? __list_del_entry_valid_or_report.cold+0xf/0x6f
[ 1136.120806] move_linked_works+0x4a/0xa0
[ 1136.124733] worker_thread+0x216/0x3a0
[ 1136.128485] ? __pfx_worker_thread+0x10/0x10
[ 1136.132758] kthread+0xfa/0x240
[ 1136.135904] ? __pfx_kthread+0x10/0x10
[ 1136.139657] ret_from_fork+0x31/0x50
[ 1136.143236] ? __pfx_kthread+0x10/0x10
[ 1136.146988] ret_from_fork_asm+0x1a/0x30
[ 1136.150915] </TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: simple-card-utils: Don't use __free(device_node) at graph_util_parse_dai()
commit 419d1918105e ("ASoC: simple-card-utils: use __free(device_node) for
device node") uses __free(device_node) for dlc->of_node, but we need to
keep it while driver is in use.
Don't use __free(device_node) in graph_util_parse_dai(). |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix null pointer dereference error in generate_encryptionkey
If client send two session setups with krb5 authenticate to ksmbd,
null pointer dereference error in generate_encryptionkey could happen.
sess->Preauth_HashValue is set to NULL if session is valid.
So this patch skip generate encryption key if session is valid. |
| In the Linux kernel, the following vulnerability has been resolved:
media: uvcvideo: Mark invalid entities with id UVC_INVALID_ENTITY_ID
Per UVC 1.1+ specification 3.7.2, units and terminals must have a non-zero
unique ID.
```
Each Unit and Terminal within the video function is assigned a unique
identification number, the Unit ID (UID) or Terminal ID (TID), contained in
the bUnitID or bTerminalID field of the descriptor. The value 0x00 is
reserved for undefined ID,
```
If we add a new entity with id 0 or a duplicated ID, it will be marked
as UVC_INVALID_ENTITY_ID.
In a previous attempt commit 3dd075fe8ebb ("media: uvcvideo: Require
entities to have a non-zero unique ID"), we ignored all the invalid units,
this broke a lot of non-compatible cameras. Hopefully we are more lucky
this time.
This also prevents some syzkaller reproducers from triggering warnings due
to a chain of entities referring to themselves. In one particular case, an
Output Unit is connected to an Input Unit, both with the same ID of 1. But
when looking up for the source ID of the Output Unit, that same entity is
found instead of the input entity, which leads to such warnings.
In another case, a backward chain was considered finished as the source ID
was 0. Later on, that entity was found, but its pads were not valid.
Here is a sample stack trace for one of those cases.
[ 20.650953] usb 1-1: new high-speed USB device number 2 using dummy_hcd
[ 20.830206] usb 1-1: Using ep0 maxpacket: 8
[ 20.833501] usb 1-1: config 0 descriptor??
[ 21.038518] usb 1-1: string descriptor 0 read error: -71
[ 21.038893] usb 1-1: Found UVC 0.00 device <unnamed> (2833:0201)
[ 21.039299] uvcvideo 1-1:0.0: Entity type for entity Output 1 was not initialized!
[ 21.041583] uvcvideo 1-1:0.0: Entity type for entity Input 1 was not initialized!
[ 21.042218] ------------[ cut here ]------------
[ 21.042536] WARNING: CPU: 0 PID: 9 at drivers/media/mc/mc-entity.c:1147 media_create_pad_link+0x2c4/0x2e0
[ 21.043195] Modules linked in:
[ 21.043535] CPU: 0 UID: 0 PID: 9 Comm: kworker/0:1 Not tainted 6.11.0-rc7-00030-g3480e43aeccf #444
[ 21.044101] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
[ 21.044639] Workqueue: usb_hub_wq hub_event
[ 21.045100] RIP: 0010:media_create_pad_link+0x2c4/0x2e0
[ 21.045508] Code: fe e8 20 01 00 00 b8 f4 ff ff ff 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc 0f 0b eb e9 0f 0b eb 0a 0f 0b eb 06 <0f> 0b eb 02 0f 0b b8 ea ff ff ff eb d4 66 2e 0f 1f 84 00 00 00 00
[ 21.046801] RSP: 0018:ffffc9000004b318 EFLAGS: 00010246
[ 21.047227] RAX: ffff888004e5d458 RBX: 0000000000000000 RCX: ffffffff818fccf1
[ 21.047719] RDX: 000000000000007b RSI: 0000000000000000 RDI: ffff888004313290
[ 21.048241] RBP: ffff888004313290 R08: 0001ffffffffffff R09: 0000000000000000
[ 21.048701] R10: 0000000000000013 R11: 0001888004313290 R12: 0000000000000003
[ 21.049138] R13: ffff888004313080 R14: ffff888004313080 R15: 0000000000000000
[ 21.049648] FS: 0000000000000000(0000) GS:ffff88803ec00000(0000) knlGS:0000000000000000
[ 21.050271] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 21.050688] CR2: 0000592cc27635b0 CR3: 000000000431c000 CR4: 0000000000750ef0
[ 21.051136] PKRU: 55555554
[ 21.051331] Call Trace:
[ 21.051480] <TASK>
[ 21.051611] ? __warn+0xc4/0x210
[ 21.051861] ? media_create_pad_link+0x2c4/0x2e0
[ 21.052252] ? report_bug+0x11b/0x1a0
[ 21.052540] ? trace_hardirqs_on+0x31/0x40
[ 21.052901] ? handle_bug+0x3d/0x70
[ 21.053197] ? exc_invalid_op+0x1a/0x50
[ 21.053511] ? asm_exc_invalid_op+0x1a/0x20
[ 21.053924] ? media_create_pad_link+0x91/0x2e0
[ 21.054364] ? media_create_pad_link+0x2c4/0x2e0
[ 21.054834] ? media_create_pad_link+0x91/0x2e0
[ 21.055131] ? _raw_spin_unlock+0x1e/0x40
[ 21.055441] ? __v4l2_device_register_subdev+0x202/0x210
[ 21.055837] uvc_mc_register_entities+0x358/0x400
[ 21.056144] uvc_register_chains+0x1
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
fbcon: Set fb_display[i]->mode to NULL when the mode is released
Recently, we discovered the following issue through syzkaller:
BUG: KASAN: slab-use-after-free in fb_mode_is_equal+0x285/0x2f0
Read of size 4 at addr ff11000001b3c69c by task syz.xxx
...
Call Trace:
<TASK>
dump_stack_lvl+0xab/0xe0
print_address_description.constprop.0+0x2c/0x390
print_report+0xb9/0x280
kasan_report+0xb8/0xf0
fb_mode_is_equal+0x285/0x2f0
fbcon_mode_deleted+0x129/0x180
fb_set_var+0xe7f/0x11d0
do_fb_ioctl+0x6a0/0x750
fb_ioctl+0xe0/0x140
__x64_sys_ioctl+0x193/0x210
do_syscall_64+0x5f/0x9c0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Based on experimentation and analysis, during framebuffer unregistration,
only the memory of fb_info->modelist is freed, without setting the
corresponding fb_display[i]->mode to NULL for the freed modes. This leads
to UAF issues during subsequent accesses. Here's an example of reproduction
steps:
1. With /dev/fb0 already registered in the system, load a kernel module
to register a new device /dev/fb1;
2. Set fb1's mode to the global fb_display[] array (via FBIOPUT_CON2FBMAP);
3. Switch console from fb to VGA (to allow normal rmmod of the ko);
4. Unload the kernel module, at this point fb1's modelist is freed, leaving
a wild pointer in fb_display[];
5. Trigger the bug via system calls through fb0 attempting to delete a mode
from fb0.
Add a check in do_unregister_framebuffer(): if the mode to be freed exists
in fb_display[], set the corresponding mode pointer to NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix out-of-bounds read in rtw_get_ie() parser
The Information Element (IE) parser rtw_get_ie() trusted the length
byte of each IE without validating that the IE body (len bytes after
the 2-byte header) fits inside the remaining frame buffer. A malformed
frame can advertise an IE length larger than the available data, causing
the parser to increment its pointer beyond the buffer end. This results
in out-of-bounds reads or, depending on the pattern, an infinite loop.
Fix by validating that (offset + 2 + len) does not exceed the limit
before accepting the IE or advancing to the next element.
This prevents OOB reads and ensures the parser terminates safely on
malformed frames. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: ufs: core: Fix use-after free in init error and remove paths
devm_blk_crypto_profile_init() registers a cleanup handler to run when
the associated (platform-) device is being released. For UFS, the
crypto private data and pointers are stored as part of the ufs_hba's
data structure 'struct ufs_hba::crypto_profile'. This structure is
allocated as part of the underlying ufshcd and therefore Scsi_host
allocation.
During driver release or during error handling in ufshcd_pltfrm_init(),
this structure is released as part of ufshcd_dealloc_host() before the
(platform-) device associated with the crypto call above is released.
Once this device is released, the crypto cleanup code will run, using
the just-released 'struct ufs_hba::crypto_profile'. This causes a
use-after-free situation:
Call trace:
kfree+0x60/0x2d8 (P)
kvfree+0x44/0x60
blk_crypto_profile_destroy_callback+0x28/0x70
devm_action_release+0x1c/0x30
release_nodes+0x6c/0x108
devres_release_all+0x98/0x100
device_unbind_cleanup+0x20/0x70
really_probe+0x218/0x2d0
In other words, the initialisation code flow is:
platform-device probe
ufshcd_pltfrm_init()
ufshcd_alloc_host()
scsi_host_alloc()
allocation of struct ufs_hba
creation of scsi-host devices
devm_blk_crypto_profile_init()
devm registration of cleanup handler using platform-device
and during error handling of ufshcd_pltfrm_init() or during driver
removal:
ufshcd_dealloc_host()
scsi_host_put()
put_device(scsi-host)
release of struct ufs_hba
put_device(platform-device)
crypto cleanup handler
To fix this use-after free, change ufshcd_alloc_host() to register a
devres action to automatically cleanup the underlying SCSI device on
ufshcd destruction, without requiring explicit calls to
ufshcd_dealloc_host(). This way:
* the crypto profile and all other ufs_hba-owned resources are
destroyed before SCSI (as they've been registered after)
* a memleak is plugged in tc-dwc-g210-pci.c remove() as a
side-effect
* EXPORT_SYMBOL_GPL(ufshcd_dealloc_host) can be removed fully as
it's not needed anymore
* no future drivers using ufshcd_alloc_host() could ever forget
adding the cleanup |
| In the Linux kernel, the following vulnerability has been resolved:
net: mctp: Don't access ifa_index when missing
In mctp_dump_addrinfo, ifa_index can be used to filter interfaces, but
only when the struct ifaddrmsg is provided. Otherwise it will be
comparing to uninitialised memory - reproducible in the syzkaller case from
dhcpd, or busybox "ip addr show".
The kernel MCTP implementation has always filtered by ifa_index, so
existing userspace programs expecting to dump MCTP addresses must
already be passing a valid ifa_index value (either 0 or a real index).
BUG: KMSAN: uninit-value in mctp_dump_addrinfo+0x208/0xac0 net/mctp/device.c:128
mctp_dump_addrinfo+0x208/0xac0 net/mctp/device.c:128
rtnl_dump_all+0x3ec/0x5b0 net/core/rtnetlink.c:4380
rtnl_dumpit+0xd5/0x2f0 net/core/rtnetlink.c:6824
netlink_dump+0x97b/0x1690 net/netlink/af_netlink.c:2309 |
| In the Linux kernel, the following vulnerability has been resolved:
drm/scheduler: signal scheduled fence when kill job
When an entity from application B is killed, drm_sched_entity_kill()
removes all jobs belonging to that entity through
drm_sched_entity_kill_jobs_work(). If application A's job depends on a
scheduled fence from application B's job, and that fence is not properly
signaled during the killing process, application A's dependency cannot be
cleared.
This leads to application A hanging indefinitely while waiting for a
dependency that will never be resolved. Fix this issue by ensuring that
scheduled fences are properly signaled when an entity is killed, allowing
dependent applications to continue execution. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: Fix dangling pointer in krb_authenticate
krb_authenticate frees sess->user and does not set the pointer
to NULL. It calls ksmbd_krb5_authenticate to reinitialise
sess->user but that function may return without doing so. If
that happens then smb2_sess_setup, which calls krb_authenticate,
will be accessing free'd memory when it later uses sess->user. |
| In the Linux kernel, the following vulnerability has been resolved:
media: dvb-frontends: w7090p: fix null-ptr-deref in w7090p_tuner_write_serpar and w7090p_tuner_read_serpar
In w7090p_tuner_write_serpar, msg is controlled by user. When msg[0].buf is null and msg[0].len is zero, former checks on msg[0].buf would be passed. If accessing msg[0].buf[2] without sanity check, null pointer deref would happen. We add
check on msg[0].len to prevent crash.
Similar commit: commit 0ed554fd769a ("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()") |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ctnetlink: remove refcounting in expectation dumpers
Same pattern as previous patch: do not keep the expectation object
alive via refcount, only store a cookie value and then use that
as the skip hint for dump resumption.
AFAICS this has the same issue as the one resolved in the conntrack
dumper, when we do
if (!refcount_inc_not_zero(&exp->use))
to increment the refcount, there is a chance that exp == last, which
causes a double-increment of the refcount and subsequent memory leak. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: Fix refcount leak for cifs_sb_tlink
Fix three refcount inconsistency issues related to `cifs_sb_tlink`.
Comments for `cifs_sb_tlink` state that `cifs_put_tlink()` needs to be
called after successful calls to `cifs_sb_tlink()`. Three calls fail to
update refcount accordingly, leading to possible resource leaks. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_ct: add seqadj extension for natted connections
Sequence adjustment may be required for FTP traffic with PASV/EPSV modes.
due to need to re-write packet payload (IP, port) on the ftp control
connection. This can require changes to the TCP length and expected
seq / ack_seq.
The easiest way to reproduce this issue is with PASV mode.
Example ruleset:
table inet ftp_nat {
ct helper ftp_helper {
type "ftp" protocol tcp
l3proto inet
}
chain prerouting {
type filter hook prerouting priority 0; policy accept;
tcp dport 21 ct state new ct helper set "ftp_helper"
}
}
table ip nat {
chain prerouting {
type nat hook prerouting priority -100; policy accept;
tcp dport 21 dnat ip prefix to ip daddr map {
192.168.100.1 : 192.168.13.2/32 }
}
chain postrouting {
type nat hook postrouting priority 100 ; policy accept;
tcp sport 21 snat ip prefix to ip saddr map {
192.168.13.2 : 192.168.100.1/32 }
}
}
Note that the ftp helper gets assigned *after* the dnat setup.
The inverse (nat after helper assign) is handled by an existing
check in nf_nat_setup_info() and will not show the problem.
Topoloy:
+-------------------+ +----------------------------------+
| FTP: 192.168.13.2 | <-> | NAT: 192.168.13.3, 192.168.100.1 |
+-------------------+ +----------------------------------+
|
+-----------------------+
| Client: 192.168.100.2 |
+-----------------------+
ftp nat changes do not work as expected in this case:
Connected to 192.168.100.1.
[..]
ftp> epsv
EPSV/EPRT on IPv4 off.
ftp> ls
227 Entering passive mode (192,168,100,1,209,129).
421 Service not available, remote server has closed connection.
Kernel logs:
Missing nfct_seqadj_ext_add() setup call
WARNING: CPU: 1 PID: 0 at net/netfilter/nf_conntrack_seqadj.c:41
[..]
__nf_nat_mangle_tcp_packet+0x100/0x160 [nf_nat]
nf_nat_ftp+0x142/0x280 [nf_nat_ftp]
help+0x4d1/0x880 [nf_conntrack_ftp]
nf_confirm+0x122/0x2e0 [nf_conntrack]
nf_hook_slow+0x3c/0xb0
..
Fix this by adding the required extension when a conntrack helper is assigned
to a connection that has a nat binding. |
| In the Linux kernel, the following vulnerability has been resolved:
timekeeping: Adjust the leap state for the correct auxiliary timekeeper
When __do_ajdtimex() was introduced to handle adjtimex for any
timekeeper, this reference to tk_core was not updated. When called on an
auxiliary timekeeper, the core timekeeper would be updated incorrectly.
This gets caught by the lock debugging diagnostics because the
timekeepers sequence lock gets written to without holding its
associated spinlock:
WARNING: include/linux/seqlock.h:226 at __do_adjtimex+0x394/0x3b0, CPU#2: test/125
aux_clock_adj (kernel/time/timekeeping.c:2979)
__do_sys_clock_adjtime (kernel/time/posix-timers.c:1161 kernel/time/posix-timers.c:1173)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131)
Update the correct auxiliary timekeeper. |
| In the Linux kernel, the following vulnerability has been resolved:
can: gs_usb: gs_usb_receive_bulk_callback(): fix URB memory leak
In gs_can_open(), the URBs for USB-in transfers are allocated, added to the
parent->rx_submitted anchor and submitted. In the complete callback
gs_usb_receive_bulk_callback(), the URB is processed and resubmitted. In
gs_can_close() the URBs are freed by calling
usb_kill_anchored_urbs(parent->rx_submitted).
However, this does not take into account that the USB framework unanchors
the URB before the complete function is called. This means that once an
in-URB has been completed, it is no longer anchored and is ultimately not
released in gs_can_close().
Fix the memory leak by anchoring the URB in the
gs_usb_receive_bulk_callback() to the parent->rx_submitted anchor. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/hugetlb: fix hugetlb_pmd_shared()
Patch series "mm/hugetlb: fixes for PMD table sharing (incl. using
mmu_gather)", v3.
One functional fix, one performance regression fix, and two related
comment fixes.
I cleaned up my prototype I recently shared [1] for the performance fix,
deferring most of the cleanups I had in the prototype to a later point.
While doing that I identified the other things.
The goal of this patch set is to be backported to stable trees "fairly"
easily. At least patch #1 and #4.
Patch #1 fixes hugetlb_pmd_shared() not detecting any sharing
Patch #2 + #3 are simple comment fixes that patch #4 interacts with.
Patch #4 is a fix for the reported performance regression due to excessive
IPI broadcasts during fork()+exit().
The last patch is all about TLB flushes, IPIs and mmu_gather.
Read: complicated
There are plenty of cleanups in the future to be had + one reasonable
optimization on x86. But that's all out of scope for this series.
Runtime tested, with a focus on fixing the performance regression using
the original reproducer [2] on x86.
This patch (of 4):
We switched from (wrongly) using the page count to an independent shared
count. Now, shared page tables have a refcount of 1 (excluding
speculative references) and instead use ptdesc->pt_share_count to identify
sharing.
We didn't convert hugetlb_pmd_shared(), so right now, we would never
detect a shared PMD table as such, because sharing/unsharing no longer
touches the refcount of a PMD table.
Page migration, like mbind() or migrate_pages() would allow for migrating
folios mapped into such shared PMD tables, even though the folios are not
exclusive. In smaps we would account them as "private" although they are
"shared", and we would be wrongly setting the PM_MMAP_EXCLUSIVE in the
pagemap interface.
Fix it by properly using ptdesc_pmd_is_shared() in hugetlb_pmd_shared(). |
| In the Linux kernel, the following vulnerability has been resolved:
virtio_net: Fix misalignment bug in struct virtnet_info
Use the new TRAILING_OVERLAP() helper to fix a misalignment bug
along with the following warning:
drivers/net/virtio_net.c:429:46: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
This helper creates a union between a flexible-array member (FAM)
and a set of members that would otherwise follow it (in this case
`u8 rss_hash_key_data[VIRTIO_NET_RSS_MAX_KEY_SIZE];`). This
overlays the trailing members (rss_hash_key_data) onto the FAM
(hash_key_data) while keeping the FAM and the start of MEMBERS aligned.
The static_assert() ensures this alignment remains.
Notice that due to tail padding in flexible `struct
virtio_net_rss_config_trailer`, `rss_trailer.hash_key_data`
(at offset 83 in struct virtnet_info) and `rss_hash_key_data` (at
offset 84 in struct virtnet_info) are misaligned by one byte. See
below:
struct virtio_net_rss_config_trailer {
__le16 max_tx_vq; /* 0 2 */
__u8 hash_key_length; /* 2 1 */
__u8 hash_key_data[]; /* 3 0 */
/* size: 4, cachelines: 1, members: 3 */
/* padding: 1 */
/* last cacheline: 4 bytes */
};
struct virtnet_info {
...
struct virtio_net_rss_config_trailer rss_trailer; /* 80 4 */
/* XXX last struct has 1 byte of padding */
u8 rss_hash_key_data[40]; /* 84 40 */
...
/* size: 832, cachelines: 13, members: 48 */
/* sum members: 801, holes: 8, sum holes: 31 */
/* paddings: 2, sum paddings: 5 */
};
After changes, those members are correctly aligned at offset 795:
struct virtnet_info {
...
union {
struct virtio_net_rss_config_trailer rss_trailer; /* 792 4 */
struct {
unsigned char __offset_to_hash_key_data[3]; /* 792 3 */
u8 rss_hash_key_data[40]; /* 795 40 */
}; /* 792 43 */
}; /* 792 44 */
...
/* size: 840, cachelines: 14, members: 47 */
/* sum members: 801, holes: 8, sum holes: 35 */
/* padding: 4 */
/* paddings: 1, sum paddings: 4 */
/* last cacheline: 8 bytes */
};
As a result, the RSS key passed to the device is shifted by 1
byte: the last byte is cut off, and instead a (possibly
uninitialized) byte is added at the beginning.
As a last note `struct virtio_net_rss_config_hdr *rss_hdr;` is also
moved to the end, since it seems those three members should stick
around together. :) |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: TC, delete flows only for existing peers
When deleting TC steering flows, iterate only over actual devcom
peers instead of assuming all possible ports exist. This avoids
touching non-existent peers and ensures cleanup is limited to
devices the driver is currently connected to.
BUG: kernel NULL pointer dereference, address: 0000000000000008
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 133c8a067 P4D 0
Oops: Oops: 0002 [#1] SMP
CPU: 19 UID: 0 PID: 2169 Comm: tc Not tainted 6.18.0+ #156 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:mlx5e_tc_del_fdb_peers_flow+0xbe/0x200 [mlx5_core]
Code: 00 00 a8 08 74 a8 49 8b 46 18 f6 c4 02 74 9f 4c 8d bf a0 12 00 00 4c 89 ff e8 0e e7 96 e1 49 8b 44 24 08 49 8b 0c 24 4c 89 ff <48> 89 41 08 48 89 08 49 89 2c 24 49 89 5c 24 08 e8 7d ce 96 e1 49
RSP: 0018:ff11000143867528 EFLAGS: 00010246
RAX: 0000000000000000 RBX: dead000000000122 RCX: 0000000000000000
RDX: ff11000143691580 RSI: ff110001026e5000 RDI: ff11000106f3d2a0
RBP: dead000000000100 R08: 00000000000003fd R09: 0000000000000002
R10: ff11000101c75690 R11: ff1100085faea178 R12: ff11000115f0ae78
R13: 0000000000000000 R14: ff11000115f0a800 R15: ff11000106f3d2a0
FS: 00007f35236bf740(0000) GS:ff110008dc809000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 0000000157a01001 CR4: 0000000000373eb0
Call Trace:
<TASK>
mlx5e_tc_del_flow+0x46/0x270 [mlx5_core]
mlx5e_flow_put+0x25/0x50 [mlx5_core]
mlx5e_delete_flower+0x2a6/0x3e0 [mlx5_core]
tc_setup_cb_reoffload+0x20/0x80
fl_reoffload+0x26f/0x2f0 [cls_flower]
? mlx5e_tc_reoffload_flows_work+0xc0/0xc0 [mlx5_core]
? mlx5e_tc_reoffload_flows_work+0xc0/0xc0 [mlx5_core]
tcf_block_playback_offloads+0x9e/0x1c0
tcf_block_unbind+0x7b/0xd0
tcf_block_setup+0x186/0x1d0
tcf_block_offload_cmd.isra.0+0xef/0x130
tcf_block_offload_unbind+0x43/0x70
__tcf_block_put+0x85/0x160
ingress_destroy+0x32/0x110 [sch_ingress]
__qdisc_destroy+0x44/0x100
qdisc_graft+0x22b/0x610
tc_get_qdisc+0x183/0x4d0
rtnetlink_rcv_msg+0x2d7/0x3d0
? rtnl_calcit.isra.0+0x100/0x100
netlink_rcv_skb+0x53/0x100
netlink_unicast+0x249/0x320
? __alloc_skb+0x102/0x1f0
netlink_sendmsg+0x1e3/0x420
__sock_sendmsg+0x38/0x60
____sys_sendmsg+0x1ef/0x230
? copy_msghdr_from_user+0x6c/0xa0
___sys_sendmsg+0x7f/0xc0
? ___sys_recvmsg+0x8a/0xc0
? __sys_sendto+0x119/0x180
__sys_sendmsg+0x61/0xb0
do_syscall_64+0x55/0x640
entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f35238bb764
Code: 15 b9 86 0c 00 f7 d8 64 89 02 b8 ff ff ff ff eb bf 0f 1f 44 00 00 f3 0f 1e fa 80 3d e5 08 0d 00 00 74 13 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 4c c3 0f 1f 00 55 48 89 e5 48 83 ec 20 89 55
RSP: 002b:00007ffed4c35638 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000055a2efcc75e0 RCX: 00007f35238bb764
RDX: 0000000000000000 RSI: 00007ffed4c356a0 RDI: 0000000000000003
RBP: 00007ffed4c35710 R08: 0000000000000010 R09: 00007f3523984b20
R10: 0000000000000004 R11: 0000000000000202 R12: 00007ffed4c35790
R13: 000000006947df8f R14: 000055a2efcc75e0 R15: 00007ffed4c35780 |
