| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| 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:
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:
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:
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:
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:
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:
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:
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:
mmc: mxcmmc: fix return value check of mmc_add_host()
mmc_add_host() may return error, if we ignore its return value, the memory
that allocated in mmc_alloc_host() will be leaked and it will lead a kernel
crash because of deleting not added device in the remove path.
So 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:
ext4: fix inode leak in ext4_xattr_inode_create() on an error path
There is issue as follows when do setxattr with inject fault:
[localhost]# fsck.ext4 -fn /dev/sda
e2fsck 1.46.6-rc1 (12-Sep-2022)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Unattached zero-length inode 15. Clear? no
Unattached inode 15
Connect to /lost+found? no
Pass 5: Checking group summary information
/dev/sda: ********** WARNING: Filesystem still has errors **********
/dev/sda: 15/655360 files (0.0% non-contiguous), 66755/2621440 blocks
This occurs in 'ext4_xattr_inode_create()'. If 'ext4_mark_inode_dirty()'
fails, dropping i_nlink of the inode is needed. Or will lead to inode leak. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix type of second parameter in odn_edit_dpm_table() callback
With clang's kernel control flow integrity (kCFI, CONFIG_CFI_CLANG),
indirect call targets are validated against the expected function
pointer prototype to make sure the call target is valid to help mitigate
ROP attacks. If they are not identical, there is a failure at run time,
which manifests as either a kernel panic or thread getting killed. A
proposed warning in clang aims to catch these at compile time, which
reveals:
drivers/gpu/drm/amd/amdgpu/../pm/swsmu/amdgpu_smu.c:3008:29: error: incompatible function pointer types initializing 'int (*)(void *, uint32_t, long *, uint32_t)' (aka 'int (*)(void *, unsigned int, long *, unsigned int)') with an expression of type 'int (void *, enum PP_OD_DPM_TABLE_COMMAND, long *, uint32_t)' (aka 'int (void *, enum PP_OD_DPM_TABLE_COMMAND, long *, unsigned int)') [-Werror,-Wincompatible-function-pointer-types-strict]
.odn_edit_dpm_table = smu_od_edit_dpm_table,
^~~~~~~~~~~~~~~~~~~~~
1 error generated.
There are only two implementations of ->odn_edit_dpm_table() in 'struct
amd_pm_funcs': smu_od_edit_dpm_table() and pp_odn_edit_dpm_table(). One
has a second parameter type of 'enum PP_OD_DPM_TABLE_COMMAND' and the
other uses 'u32'. Ultimately, smu_od_edit_dpm_table() calls
->od_edit_dpm_table() from 'struct pptable_funcs' and
pp_odn_edit_dpm_table() calls ->odn_edit_dpm_table() from 'struct
pp_hwmgr_func', which both have a second parameter type of 'enum
PP_OD_DPM_TABLE_COMMAND'.
Update the type parameter in both the prototype in 'struct amd_pm_funcs'
and pp_odn_edit_dpm_table() to 'enum PP_OD_DPM_TABLE_COMMAND', which
cleans up the warning. |
| 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:
drm/virtio: Check whether transferred 2D BO is shmem
Transferred 2D BO always must be a shmem BO. Add check for that to prevent
NULL dereference if userspace passes a VRAM BO. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix memory leak in ocfs2_mount_volume()
There is a memory leak reported by kmemleak:
unreferenced object 0xffff88810cc65e60 (size 32):
comm "mount.ocfs2", pid 23753, jiffies 4302528942 (age 34735.105s)
hex dump (first 32 bytes):
10 00 00 00 00 00 00 00 00 01 01 01 01 01 01 01 ................
01 01 01 01 01 01 01 01 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff8170f73d>] __kmalloc+0x4d/0x150
[<ffffffffa0ac3f51>] ocfs2_compute_replay_slots+0x121/0x330 [ocfs2]
[<ffffffffa0b65165>] ocfs2_check_volume+0x485/0x900 [ocfs2]
[<ffffffffa0b68129>] ocfs2_mount_volume.isra.0+0x1e9/0x650 [ocfs2]
[<ffffffffa0b7160b>] ocfs2_fill_super+0xe0b/0x1740 [ocfs2]
[<ffffffff818e1fe2>] mount_bdev+0x312/0x400
[<ffffffff819a086d>] legacy_get_tree+0xed/0x1d0
[<ffffffff818de82d>] vfs_get_tree+0x7d/0x230
[<ffffffff81957f92>] path_mount+0xd62/0x1760
[<ffffffff81958a5a>] do_mount+0xca/0xe0
[<ffffffff81958d3c>] __x64_sys_mount+0x12c/0x1a0
[<ffffffff82f26f15>] do_syscall_64+0x35/0x80
[<ffffffff8300006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
This call stack is related to two problems. Firstly, the ocfs2 super uses
"replay_map" to trace online/offline slots, in order to recover offline
slots during recovery and mount. But when ocfs2_truncate_log_init()
returns an error in ocfs2_mount_volume(), the memory of "replay_map" will
not be freed in error handling path. Secondly, the memory of "replay_map"
will not be freed if d_make_root() returns an error in ocfs2_fill_super().
But the memory of "replay_map" will be freed normally when completing
recovery and mount in ocfs2_complete_mount_recovery().
Fix the first problem by adding error handling path to free "replay_map"
when ocfs2_truncate_log_init() fails. And fix the second problem by
calling ocfs2_free_replay_slots(osb) in the error handling path
"out_dismount". In addition, since ocfs2_free_replay_slots() is static,
it is necessary to remove its static attribute and declare it in header
file. |
| In the Linux kernel, the following vulnerability has been resolved:
rcu: Fix __this_cpu_read() lockdep warning in rcu_force_quiescent_state()
Running rcutorture with non-zero fqs_duration module parameter in a
kernel built with CONFIG_PREEMPTION=y results in the following splat:
BUG: using __this_cpu_read() in preemptible [00000000]
code: rcu_torture_fqs/398
caller is __this_cpu_preempt_check+0x13/0x20
CPU: 3 PID: 398 Comm: rcu_torture_fqs Not tainted 6.0.0-rc1-yoctodev-standard+
Call Trace:
<TASK>
dump_stack_lvl+0x5b/0x86
dump_stack+0x10/0x16
check_preemption_disabled+0xe5/0xf0
__this_cpu_preempt_check+0x13/0x20
rcu_force_quiescent_state.part.0+0x1c/0x170
rcu_force_quiescent_state+0x1e/0x30
rcu_torture_fqs+0xca/0x160
? rcu_torture_boost+0x430/0x430
kthread+0x192/0x1d0
? kthread_complete_and_exit+0x30/0x30
ret_from_fork+0x22/0x30
</TASK>
The problem is that rcu_force_quiescent_state() uses __this_cpu_read()
in preemptible code instead of the proper raw_cpu_read(). This commit
therefore changes __this_cpu_read() to raw_cpu_read(). |
| 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:
netdevsim: fix memory leak in nsim_bus_dev_new()
If device_register() failed in nsim_bus_dev_new(), the value of reference
in nsim_bus_dev->dev is 1. obj->name in nsim_bus_dev->dev will not be
released.
unreferenced object 0xffff88810352c480 (size 16):
comm "echo", pid 5691, jiffies 4294945921 (age 133.270s)
hex dump (first 16 bytes):
6e 65 74 64 65 76 73 69 6d 31 00 00 00 00 00 00 netdevsim1......
backtrace:
[<000000005e2e5e26>] __kmalloc_node_track_caller+0x3a/0xb0
[<0000000094ca4fc8>] kvasprintf+0xc3/0x160
[<00000000aad09bcc>] kvasprintf_const+0x55/0x180
[<000000009bac868d>] kobject_set_name_vargs+0x56/0x150
[<000000007c1a5d70>] dev_set_name+0xbb/0xf0
[<00000000ad0d126b>] device_add+0x1f8/0x1cb0
[<00000000c222ae24>] new_device_store+0x3b6/0x5e0
[<0000000043593421>] bus_attr_store+0x72/0xa0
[<00000000cbb1833a>] sysfs_kf_write+0x106/0x160
[<00000000d0dedb8a>] kernfs_fop_write_iter+0x3a8/0x5a0
[<00000000770b66e2>] vfs_write+0x8f0/0xc80
[<0000000078bb39be>] ksys_write+0x106/0x210
[<00000000005e55a4>] do_syscall_64+0x35/0x80
[<00000000eaa40bbc>] entry_SYSCALL_64_after_hwframe+0x46/0xb0 |
| In the Linux kernel, the following vulnerability has been resolved:
jbd2: fix potential buffer head reference count leak
As in 'jbd2_fc_wait_bufs' if buffer isn't uptodate, will return -EIO without
update 'journal->j_fc_off'. But 'jbd2_fc_release_bufs' will release buffer head
from ‘j_fc_off - 1’ if 'bh' is NULL will terminal release which will lead to
buffer head buffer head reference count leak.
To solve above issue, update 'journal->j_fc_off' before return -EIO. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: mts64: fix possible null-ptr-defer in snd_mts64_interrupt
I got a null-ptr-defer error report when I do the following tests
on the qemu platform:
make defconfig and CONFIG_PARPORT=m, CONFIG_PARPORT_PC=m,
CONFIG_SND_MTS64=m
Then making test scripts:
cat>test_mod1.sh<<EOF
modprobe snd-mts64
modprobe snd-mts64
EOF
Executing the script, perhaps several times, we will get a null-ptr-defer
report, as follow:
syzkaller:~# ./test_mod.sh
snd_mts64: probe of snd_mts64.0 failed with error -5
modprobe: ERROR: could not insert 'snd_mts64': No such device
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] PREEMPT SMP PTI
CPU: 0 PID: 205 Comm: modprobe Not tainted 6.1.0-rc8-00588-g76dcd734eca2 #6
Call Trace:
<IRQ>
snd_mts64_interrupt+0x24/0xa0 [snd_mts64]
parport_irq_handler+0x37/0x50 [parport]
__handle_irq_event_percpu+0x39/0x190
handle_irq_event_percpu+0xa/0x30
handle_irq_event+0x2f/0x50
handle_edge_irq+0x99/0x1b0
__common_interrupt+0x5d/0x100
common_interrupt+0xa0/0xc0
</IRQ>
<TASK>
asm_common_interrupt+0x22/0x40
RIP: 0010:_raw_write_unlock_irqrestore+0x11/0x30
parport_claim+0xbd/0x230 [parport]
snd_mts64_probe+0x14a/0x465 [snd_mts64]
platform_probe+0x3f/0xa0
really_probe+0x129/0x2c0
__driver_probe_device+0x6d/0xc0
driver_probe_device+0x1a/0xa0
__device_attach_driver+0x7a/0xb0
bus_for_each_drv+0x62/0xb0
__device_attach+0xe4/0x180
bus_probe_device+0x82/0xa0
device_add+0x550/0x920
platform_device_add+0x106/0x220
snd_mts64_attach+0x2e/0x80 [snd_mts64]
port_check+0x14/0x20 [parport]
bus_for_each_dev+0x6e/0xc0
__parport_register_driver+0x7c/0xb0 [parport]
snd_mts64_module_init+0x31/0x1000 [snd_mts64]
do_one_initcall+0x3c/0x1f0
do_init_module+0x46/0x1c6
load_module+0x1d8d/0x1e10
__do_sys_finit_module+0xa2/0xf0
do_syscall_64+0x37/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
</TASK>
Kernel panic - not syncing: Fatal exception in interrupt
Rebooting in 1 seconds..
The mts wa not initialized during interrupt, we add check for
mts to fix this bug. |
| 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. |