| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
net: stream: purge sk_error_queue in sk_stream_kill_queues()
Changheon Lee reported TCP socket leaks, with a nice repro.
It seems we leak TCP sockets with the following sequence:
1) SOF_TIMESTAMPING_TX_ACK is enabled on the socket.
Each ACK will cook an skb put in error queue, from __skb_tstamp_tx().
__skb_tstamp_tx() is using skb_clone(), unless
SOF_TIMESTAMPING_OPT_TSONLY was also requested.
2) If the application is also using MSG_ZEROCOPY, then we put in the
error queue cloned skbs that had a struct ubuf_info attached to them.
Whenever an struct ubuf_info is allocated, sock_zerocopy_alloc()
does a sock_hold().
As long as the cloned skbs are still in sk_error_queue,
socket refcount is kept elevated.
3) Application closes the socket, while error queue is not empty.
Since tcp_close() no longer purges the socket error queue,
we might end up with a TCP socket with at least one skb in
error queue keeping the socket alive forever.
This bug can be (ab)used to consume all kernel memory
and freeze the host.
We need to purge the error queue, with proper synchronization
against concurrent writers. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: snic: Fix possible UAF in snic_tgt_create()
Smatch reports a warning as follows:
drivers/scsi/snic/snic_disc.c:307 snic_tgt_create() warn:
'&tgt->list' not removed from list
If device_add() fails in snic_tgt_create(), tgt will be freed, but
tgt->list will not be removed from snic->disc.tgt_list, then list traversal
may cause UAF.
Remove from snic->disc.tgt_list before free(). |
| In the Linux kernel, the following vulnerability has been resolved:
dm clone: Fix UAF in clone_dtr()
Dm_clone also has the same UAF problem when dm_resume()
and dm_destroy() are concurrent.
Therefore, cancelling timer again in clone_dtr(). |
| In the Linux kernel, the following vulnerability has been resolved:
mmc: via-sdmmc: fix return value check of mmc_add_host()
mmc_add_host() may return error, if we ignore its return value,
it will lead two issues:
1. The memory that allocated in mmc_alloc_host() is leaked.
2. In the remove() path, mmc_remove_host() will be called to
delete device, but it's not added yet, it will lead a kernel
crash because of null-ptr-deref in device_del().
Fix this by checking the return value and goto error path which
will call mmc_free_host(). |
| In the Linux kernel, the following vulnerability has been resolved:
drm/bridge: it6505: Initialize AUX channel in it6505_i2c_probe
During device boot, the HPD interrupt could be triggered before the DRM
subsystem registers it6505 as a DRM bridge. In such cases, the driver
tries to access AUX channel and causes NULL pointer dereference.
Initializing the AUX channel earlier to prevent such error. |
| In the Linux kernel, the following vulnerability has been resolved:
drivers: dio: fix possible memory leak in dio_init()
If device_register() returns error, the 'dev' and name needs be
freed. Add a release function, and then call put_device() in the
error path, so the name is freed in kobject_cleanup() and to the
'dev' is freed in release function. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: ipr: Fix WARNING in ipr_init()
ipr_init() will not call unregister_reboot_notifier() when
pci_register_driver() fails, which causes a WARNING. Call
unregister_reboot_notifier() when pci_register_driver() fails.
notifier callback ipr_halt [ipr] already registered
WARNING: CPU: 3 PID: 299 at kernel/notifier.c:29
notifier_chain_register+0x16d/0x230
Modules linked in: ipr(+) xhci_pci_renesas xhci_hcd ehci_hcd usbcore
led_class gpu_sched drm_buddy video wmi drm_ttm_helper ttm
drm_display_helper drm_kms_helper drm drm_panel_orientation_quirks
agpgart cfbft
CPU: 3 PID: 299 Comm: modprobe Tainted: G W
6.1.0-rc1-00190-g39508d23b672-dirty #332
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
RIP: 0010:notifier_chain_register+0x16d/0x230
Call Trace:
<TASK>
__blocking_notifier_chain_register+0x73/0xb0
ipr_init+0x30/0x1000 [ipr]
do_one_initcall+0xdb/0x480
do_init_module+0x1cf/0x680
load_module+0x6a50/0x70a0
__do_sys_finit_module+0x12f/0x1c0
do_syscall_64+0x3f/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd |
| In the Linux kernel, the following vulnerability has been resolved:
net: broadcom: bcm4908_enet: update TX stats after actual transmission
Queueing packets doesn't guarantee their transmission. Update TX stats
after hardware confirms consuming submitted data.
This also fixes a possible race and NULL dereference.
bcm4908_enet_start_xmit() could try to access skb after freeing it in
the bcm4908_enet_poll_tx(). |
| In the Linux kernel, the following vulnerability has been resolved:
vhost_vdpa: fix the crash in unmap a large memory
While testing in vIOMMU, sometimes Guest will unmap very large memory,
which will cause the crash. To fix this, add a new function
vhost_vdpa_general_unmap(). This function will only unmap the memory
that saved in iotlb.
Call Trace:
[ 647.820144] ------------[ cut here ]------------
[ 647.820848] kernel BUG at drivers/iommu/intel/iommu.c:1174!
[ 647.821486] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[ 647.822082] CPU: 10 PID: 1181 Comm: qemu-system-x86 Not tainted 6.0.0-rc1home_lulu_2452_lulu7_vhost+ #62
[ 647.823139] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-29-g6a62e0cb0dfe-prebuilt.qem4
[ 647.824365] RIP: 0010:domain_unmap+0x48/0x110
[ 647.825424] Code: 48 89 fb 8d 4c f6 1e 39 c1 0f 4f c8 83 e9 0c 83 f9 3f 7f 18 48 89 e8 48 d3 e8 48 85 c0 75 59
[ 647.828064] RSP: 0018:ffffae5340c0bbf0 EFLAGS: 00010202
[ 647.828973] RAX: 0000000000000001 RBX: ffff921793d10540 RCX: 000000000000001b
[ 647.830083] RDX: 00000000080000ff RSI: 0000000000000001 RDI: ffff921793d10540
[ 647.831214] RBP: 0000000007fc0100 R08: ffffae5340c0bcd0 R09: 0000000000000003
[ 647.832388] R10: 0000007fc0100000 R11: 0000000000100000 R12: 00000000080000ff
[ 647.833668] R13: ffffae5340c0bcd0 R14: ffff921793d10590 R15: 0000008000100000
[ 647.834782] FS: 00007f772ec90640(0000) GS:ffff921ce7a80000(0000) knlGS:0000000000000000
[ 647.836004] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 647.836990] CR2: 00007f02c27a3a20 CR3: 0000000101b0c006 CR4: 0000000000372ee0
[ 647.838107] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 647.839283] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 647.840666] Call Trace:
[ 647.841437] <TASK>
[ 647.842107] intel_iommu_unmap_pages+0x93/0x140
[ 647.843112] __iommu_unmap+0x91/0x1b0
[ 647.844003] iommu_unmap+0x6a/0x95
[ 647.844885] vhost_vdpa_unmap+0x1de/0x1f0 [vhost_vdpa]
[ 647.845985] vhost_vdpa_process_iotlb_msg+0xf0/0x90b [vhost_vdpa]
[ 647.847235] ? _raw_spin_unlock+0x15/0x30
[ 647.848181] ? _copy_from_iter+0x8c/0x580
[ 647.849137] vhost_chr_write_iter+0xb3/0x430 [vhost]
[ 647.850126] vfs_write+0x1e4/0x3a0
[ 647.850897] ksys_write+0x53/0xd0
[ 647.851688] do_syscall_64+0x3a/0x90
[ 647.852508] entry_SYSCALL_64_after_hwframe+0x63/0xcd
[ 647.853457] RIP: 0033:0x7f7734ef9f4f
[ 647.854408] Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 29 76 f8 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c8
[ 647.857217] RSP: 002b:00007f772ec8f040 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
[ 647.858486] RAX: ffffffffffffffda RBX: 00000000fef00000 RCX: 00007f7734ef9f4f
[ 647.859713] RDX: 0000000000000048 RSI: 00007f772ec8f090 RDI: 0000000000000010
[ 647.860942] RBP: 00007f772ec8f1a0 R08: 0000000000000000 R09: 0000000000000000
[ 647.862206] R10: 0000000000000001 R11: 0000000000000293 R12: 0000000000000010
[ 647.863446] R13: 0000000000000002 R14: 0000000000000000 R15: ffffffff01100000
[ 647.864692] </TASK>
[ 647.865458] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs v]
[ 647.874688] ---[ end trace 0000000000000000 ]--- |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7921: fix use after free in mt7921_acpi_read()
Don't dereference "sar_root" after it has been freed. |
| In the Linux kernel, the following vulnerability has been resolved:
pstore: Avoid kcore oops by vmap()ing with VM_IOREMAP
An oops can be induced by running 'cat /proc/kcore > /dev/null' on
devices using pstore with the ram backend because kmap_atomic() assumes
lowmem pages are accessible with __va().
Unable to handle kernel paging request at virtual address ffffff807ff2b000
Mem abort info:
ESR = 0x96000006
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x06: level 2 translation fault
Data abort info:
ISV = 0, ISS = 0x00000006
CM = 0, WnR = 0
swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000081d87000
[ffffff807ff2b000] pgd=180000017fe18003, p4d=180000017fe18003, pud=180000017fe18003, pmd=0000000000000000
Internal error: Oops: 96000006 [#1] PREEMPT SMP
Modules linked in: dm_integrity
CPU: 7 PID: 21179 Comm: perf Not tainted 5.15.67-10882-ge4eb2eb988cd #1 baa443fb8e8477896a370b31a821eb2009f9bfba
Hardware name: Google Lazor (rev3 - 8) (DT)
pstate: a0400009 (NzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __memcpy+0x110/0x260
lr : vread+0x194/0x294
sp : ffffffc013ee39d0
x29: ffffffc013ee39f0 x28: 0000000000001000 x27: ffffff807ff2b000
x26: 0000000000001000 x25: ffffffc0085a2000 x24: ffffff802d4b3000
x23: ffffff80f8a60000 x22: ffffff802d4b3000 x21: ffffffc0085a2000
x20: ffffff8080b7bc68 x19: 0000000000001000 x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000 x15: ffffffd3073f2e60
x14: ffffffffad588000 x13: 0000000000000000 x12: 0000000000000001
x11: 00000000000001a2 x10: 00680000fff2bf0b x9 : 03fffffff807ff2b
x8 : 0000000000000001 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffffff802d4b4000 x4 : ffffff807ff2c000 x3 : ffffffc013ee3a78
x2 : 0000000000001000 x1 : ffffff807ff2b000 x0 : ffffff802d4b3000
Call trace:
__memcpy+0x110/0x260
read_kcore+0x584/0x778
proc_reg_read+0xb4/0xe4
During early boot, memblock reserves the pages for the ramoops reserved
memory node in DT that would otherwise be part of the direct lowmem
mapping. Pstore's ram backend reuses those reserved pages to change the
memory type (writeback or non-cached) by passing the pages to vmap()
(see pfn_to_page() usage in persistent_ram_vmap() for more details) with
specific flags. When read_kcore() starts iterating over the vmalloc
region, it runs over the virtual address that vmap() returned for
ramoops. In aligned_vread() the virtual address is passed to
vmalloc_to_page() which returns the page struct for the reserved lowmem
area. That lowmem page is passed to kmap_atomic(), which effectively
calls page_to_virt() that assumes a lowmem page struct must be directly
accessible with __va() and friends. These pages are mapped via vmap()
though, and the lowmem mapping was never made, so accessing them via the
lowmem virtual address oopses like above.
Let's side-step this problem by passing VM_IOREMAP to vmap(). This will
tell vread() to not include the ramoops region in the kcore. Instead the
area will look like a bunch of zeros. The alternative is to teach kmap()
about vmalloc areas that intersect with lowmem. Presumably such a change
isn't a one-liner, and there isn't much interest in inspecting the
ramoops region in kcore files anyway, so the most expedient route is
taken for now. |
| In the Linux kernel, the following vulnerability has been resolved:
NFSv4: Fix a credential leak in _nfs4_discover_trunking() |
| In the Linux kernel, the following vulnerability has been resolved:
nfc: virtual_ncidev: Fix memory leak in virtual_nci_send()
skb should be free in virtual_nci_send(), otherwise kmemleak will report
memleak.
Steps for reproduction (simulated in qemu):
cd tools/testing/selftests/nci
make
./nci_dev
BUG: memory leak
unreferenced object 0xffff888107588000 (size 208):
comm "nci_dev", pid 206, jiffies 4294945376 (age 368.248s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<000000008d94c8fd>] __alloc_skb+0x1da/0x290
[<00000000278bc7f8>] nci_send_cmd+0xa3/0x350
[<0000000081256a22>] nci_reset_req+0x6b/0xa0
[<000000009e721112>] __nci_request+0x90/0x250
[<000000005d556e59>] nci_dev_up+0x217/0x5b0
[<00000000e618ce62>] nfc_dev_up+0x114/0x220
[<00000000981e226b>] nfc_genl_dev_up+0x94/0xe0
[<000000009bb03517>] genl_family_rcv_msg_doit.isra.14+0x228/0x2d0
[<00000000b7f8c101>] genl_rcv_msg+0x35c/0x640
[<00000000c94075ff>] netlink_rcv_skb+0x11e/0x350
[<00000000440cfb1e>] genl_rcv+0x24/0x40
[<0000000062593b40>] netlink_unicast+0x43f/0x640
[<000000001d0b13cc>] netlink_sendmsg+0x73a/0xbf0
[<000000003272487f>] __sys_sendto+0x324/0x370
[<00000000ef9f1747>] __x64_sys_sendto+0xdd/0x1b0
[<000000001e437841>] do_syscall_64+0x3f/0x90 |
| In the Linux kernel, the following vulnerability has been resolved:
of: overlay: fix null pointer dereferencing in find_dup_cset_node_entry() and find_dup_cset_prop()
When kmalloc() fail to allocate memory in kasprintf(), fn_1 or fn_2 will
be NULL, and strcmp() will cause null pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: prevent leak of lsm program after failed attach
In [0], we added the ability to bpf_prog_attach LSM programs to cgroups,
but in our validation to make sure the prog is meant to be attached to
BPF_LSM_CGROUP, we return too early if the check fails. This results in
lack of decrementing prog's refcnt (through bpf_prog_put)
leaving the LSM program alive past the point of the expected lifecycle.
This fix allows for the decrement to take place.
[0] https://lore.kernel.org/all/20220628174314.1216643-4-sdf@google.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: fix memory leak in mlx5e_ptp_open
When kvzalloc_node or kvzalloc failed in mlx5e_ptp_open, the memory
pointed by "c" or "cparams" is not freed, which can lead to a memory
leak. Fix by freeing the array in the error path. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/mlx4: Prevent shift wrapping in set_user_sq_size()
The ucmd->log_sq_bb_count variable is controlled by the user so this
shift can wrap. Fix it by using check_shl_overflow() in the same way
that it was done in commit 515f60004ed9 ("RDMA/hns: Prevent undefined
behavior in hns_roce_set_user_sq_size()"). |
| In the Linux kernel, the following vulnerability has been resolved:
of: unittest: fix null pointer dereferencing in of_unittest_find_node_by_name()
when kmalloc() fail to allocate memory in kasprintf(), name
or full_name will be NULL, strcmp() will cause
null pointer dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
igc: Fix Kernel Panic during ndo_tx_timeout callback
The Xeon validation group has been carrying out some loaded tests
with various HW configurations, and they have seen some transmit
queue time out happening during the test. This will cause the
reset adapter function to be called by igc_tx_timeout().
Similar race conditions may arise when the interface is being brought
down and up in igc_reinit_locked(), an interrupt being generated, and
igc_clean_tx_irq() being called to complete the TX.
When the igc_tx_timeout() function is invoked, this patch will turn
off all TX ring HW queues during igc_down() process. TX ring HW queues
will be activated again during the igc_configure_tx_ring() process
when performing the igc_up() procedure later.
This patch also moved existing igc_disable_tx_ring_hw() to avoid using
forward declaration.
Kernel trace:
[ 7678.747813] ------------[ cut here ]------------
[ 7678.757914] NETDEV WATCHDOG: enp1s0 (igc): transmit queue 2 timed out
[ 7678.770117] WARNING: CPU: 0 PID: 13 at net/sched/sch_generic.c:525 dev_watchdog+0x1ae/0x1f0
[ 7678.784459] Modules linked in: xt_conntrack nft_chain_nat xt_MASQUERADE xt_addrtype nft_compat
nf_tables nfnetlink br_netfilter bridge stp llc overlay dm_mod emrcha(PO) emriio(PO) rktpm(PO)
cegbuf_mod(PO) patch_update(PO) se(PO) sgx_tgts(PO) mktme(PO) keylocker(PO) svtdx(PO) svfs_pci_hotplug(PO)
vtd_mod(PO) davemem(PO) svmabort(PO) svindexio(PO) usbx2(PO) ehci_sched(PO) svheartbeat(PO) ioapic(PO)
sv8259(PO) svintr(PO) lt(PO) pcierootport(PO) enginefw_mod(PO) ata(PO) smbus(PO) spiflash_cdf(PO) arden(PO)
dsa_iax(PO) oobmsm_punit(PO) cpm(PO) svkdb(PO) ebg_pch(PO) pch(PO) sviotargets(PO) svbdf(PO) svmem(PO)
svbios(PO) dram(PO) svtsc(PO) targets(PO) superio(PO) svkernel(PO) cswitch(PO) mcf(PO) pentiumIII_mod(PO)
fs_svfs(PO) mdevdefdb(PO) svfs_os_services(O) ixgbe mdio mdio_devres libphy emeraldrapids_svdefs(PO)
regsupport(O) libnvdimm nls_cp437 snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_intel
snd_intel_dspcfg snd_hda_codec snd_hwdep x86_pkg_temp_thermal snd_hda_core snd_pcm snd_timer isst_if_mbox_pci
[ 7678.784496] input_leds isst_if_mmio sg snd isst_if_common soundcore wmi button sad9(O) drm fuse backlight
configfs efivarfs ip_tables x_tables vmd sdhci led_class rtl8150 r8152 hid_generic pegasus mmc_block usbhid
mmc_core hid megaraid_sas ixgb igb i2c_algo_bit ice i40e hpsa scsi_transport_sas e1000e e1000 e100 ax88179_178a
usbnet xhci_pci sd_mod xhci_hcd t10_pi crc32c_intel crc64_rocksoft igc crc64 crc_t10dif usbcore
crct10dif_generic ptp crct10dif_common usb_common pps_core
[ 7679.200403] RIP: 0010:dev_watchdog+0x1ae/0x1f0
[ 7679.210201] Code: 28 e9 53 ff ff ff 4c 89 e7 c6 05 06 42 b9 00 01 e8 17 d1 fb ff 44 89 e9 4c
89 e6 48 c7 c7 40 ad fb 81 48 89 c2 e8 52 62 82 ff <0f> 0b e9 72 ff ff ff 65 8b 05 80 7d 7c 7e
89 c0 48 0f a3 05 0a c1
[ 7679.245438] RSP: 0018:ffa00000001f7d90 EFLAGS: 00010282
[ 7679.256021] RAX: 0000000000000000 RBX: ff11000109938440 RCX: 0000000000000000
[ 7679.268710] RDX: ff11000361e26cd8 RSI: ff11000361e1b880 RDI: ff11000361e1b880
[ 7679.281314] RBP: ffa00000001f7da8 R08: ff1100035f8fffe8 R09: 0000000000027ffb
[ 7679.293840] R10: 0000000000001f0a R11: ff1100035f840000 R12: ff11000109938000
[ 7679.306276] R13: 0000000000000002 R14: dead000000000122 R15: ffa00000001f7e18
[ 7679.318648] FS: 0000000000000000(0000) GS:ff11000361e00000(0000) knlGS:0000000000000000
[ 7679.332064] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 7679.342757] CR2: 00007ffff7fca168 CR3: 000000013b08a006 CR4: 0000000000471ef8
[ 7679.354984] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 7679.367207] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[ 7679.379370] PKRU: 55555554
[ 7679.386446] Call Trace:
[ 7679.393152] <TASK>
[ 7679.399363] ? __pfx_dev_watchdog+0x10/0x10
[ 7679.407870] call_timer_fn+0x31/0x110
[ 7679.415698] e
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
zsmalloc: move LRU update from zs_map_object() to zs_malloc()
Under memory pressure, we sometimes observe the following crash:
[ 5694.832838] ------------[ cut here ]------------
[ 5694.842093] list_del corruption, ffff888014b6a448->next is LIST_POISON1 (dead000000000100)
[ 5694.858677] WARNING: CPU: 33 PID: 418824 at lib/list_debug.c:47 __list_del_entry_valid+0x42/0x80
[ 5694.961820] CPU: 33 PID: 418824 Comm: fuse_counters.s Kdump: loaded Tainted: G S 5.19.0-0_fbk3_rc3_hoangnhatpzsdynshrv41_10870_g85a9558a25de #1
[ 5694.990194] Hardware name: Wiwynn Twin Lakes MP/Twin Lakes Passive MP, BIOS YMM16 05/24/2021
[ 5695.007072] RIP: 0010:__list_del_entry_valid+0x42/0x80
[ 5695.017351] Code: 08 48 83 c2 22 48 39 d0 74 24 48 8b 10 48 39 f2 75 2c 48 8b 51 08 b0 01 48 39 f2 75 34 c3 48 c7 c7 55 d7 78 82 e8 4e 45 3b 00 <0f> 0b eb 31 48 c7 c7 27 a8 70 82 e8 3e 45 3b 00 0f 0b eb 21 48 c7
[ 5695.054919] RSP: 0018:ffffc90027aef4f0 EFLAGS: 00010246
[ 5695.065366] RAX: 41fe484987275300 RBX: ffff888008988180 RCX: 0000000000000000
[ 5695.079636] RDX: ffff88886006c280 RSI: ffff888860060480 RDI: ffff888860060480
[ 5695.093904] RBP: 0000000000000002 R08: 0000000000000000 R09: ffffc90027aef370
[ 5695.108175] R10: 0000000000000000 R11: ffffffff82fdf1c0 R12: 0000000010000002
[ 5695.122447] R13: ffff888014b6a448 R14: ffff888014b6a420 R15: 00000000138dc240
[ 5695.136717] FS: 00007f23a7d3f740(0000) GS:ffff888860040000(0000) knlGS:0000000000000000
[ 5695.152899] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 5695.164388] CR2: 0000560ceaab6ac0 CR3: 000000001c06c001 CR4: 00000000007706e0
[ 5695.178659] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 5695.192927] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 5695.207197] PKRU: 55555554
[ 5695.212602] Call Trace:
[ 5695.217486] <TASK>
[ 5695.221674] zs_map_object+0x91/0x270
[ 5695.229000] zswap_frontswap_store+0x33d/0x870
[ 5695.237885] ? do_raw_spin_lock+0x5d/0xa0
[ 5695.245899] __frontswap_store+0x51/0xb0
[ 5695.253742] swap_writepage+0x3c/0x60
[ 5695.261063] shrink_page_list+0x738/0x1230
[ 5695.269255] shrink_lruvec+0x5ec/0xcd0
[ 5695.276749] ? shrink_slab+0x187/0x5f0
[ 5695.284240] ? mem_cgroup_iter+0x6e/0x120
[ 5695.292255] shrink_node+0x293/0x7b0
[ 5695.299402] do_try_to_free_pages+0xea/0x550
[ 5695.307940] try_to_free_pages+0x19a/0x490
[ 5695.316126] __folio_alloc+0x19ff/0x3e40
[ 5695.323971] ? __filemap_get_folio+0x8a/0x4e0
[ 5695.332681] ? walk_component+0x2a8/0xb50
[ 5695.340697] ? generic_permission+0xda/0x2a0
[ 5695.349231] ? __filemap_get_folio+0x8a/0x4e0
[ 5695.357940] ? walk_component+0x2a8/0xb50
[ 5695.365955] vma_alloc_folio+0x10e/0x570
[ 5695.373796] ? walk_component+0x52/0xb50
[ 5695.381634] wp_page_copy+0x38c/0xc10
[ 5695.388953] ? filename_lookup+0x378/0xbc0
[ 5695.397140] handle_mm_fault+0x87f/0x1800
[ 5695.405157] do_user_addr_fault+0x1bd/0x570
[ 5695.413520] exc_page_fault+0x5d/0x110
[ 5695.421017] asm_exc_page_fault+0x22/0x30
After some investigation, I have found the following issue: unlike other
zswap backends, zsmalloc performs the LRU list update at the object
mapping time, rather than when the slot for the object is allocated.
This deviation was discussed and agreed upon during the review process
of the zsmalloc writeback patch series:
https://lore.kernel.org/lkml/Y3flcAXNxxrvy3ZH@cmpxchg.org/
Unfortunately, this introduces a subtle bug that occurs when there is a
concurrent store and reclaim, which interleave as follows:
zswap_frontswap_store() shrink_worker()
zs_malloc() zs_zpool_shrink()
spin_lock(&pool->lock) zs_reclaim_page()
zspage = find_get_zspage()
spin_unlock(&pool->lock)
spin_lock(&pool->lock)
zspage = list_first_entry(&pool->lru)
---truncated--- |