Security Vulnerabilities - CVEs Published In April 2024
In the Linux kernel, the following vulnerability has been resolved:
fs,hugetlb: fix NULL pointer dereference in hugetlbs_fill_super
When configuring a hugetlb filesystem via the fsconfig() syscall, there is
a possible NULL dereference in hugetlbfs_fill_super() caused by assigning
NULL to ctx->hstate in hugetlbfs_parse_param() when the requested pagesize
is non valid.
E.g: Taking the following steps:
fd = fsopen("hugetlbfs", FSOPEN_CLOEXEC);
fsconfig(fd, FSCONFIG_SET_STRING, "pagesize", "1024", 0);
fsconfig(fd, FSCONFIG_CMD_CREATE, NULL, NULL, 0);
Given that the requested "pagesize" is invalid, ctxt->hstate will be replaced
with NULL, losing its previous value, and we will print an error:
...
...
case Opt_pagesize:
ps = memparse(param->string, &rest);
ctx->hstate = h;
if (!ctx->hstate) {
pr_err("Unsupported page size %lu MB\n", ps / SZ_1M);
return -EINVAL;
}
return 0;
...
...
This is a problem because later on, we will dereference ctxt->hstate in
hugetlbfs_fill_super()
...
...
sb->s_blocksize = huge_page_size(ctx->hstate);
...
...
Causing below Oops.
Fix this by replacing cxt->hstate value only when then pagesize is known
to be valid.
kernel: hugetlbfs: Unsupported page size 0 MB
kernel: BUG: kernel NULL pointer dereference, address: 0000000000000028
kernel: #PF: supervisor read access in kernel mode
kernel: #PF: error_code(0x0000) - not-present page
kernel: PGD 800000010f66c067 P4D 800000010f66c067 PUD 1b22f8067 PMD 0
kernel: Oops: 0000 [#1] PREEMPT SMP PTI
kernel: CPU: 4 PID: 5659 Comm: syscall Tainted: G E 6.8.0-rc2-default+ #22 5a47c3fef76212addcc6eb71344aabc35190ae8f
kernel: Hardware name: Intel Corp. GROVEPORT/GROVEPORT, BIOS GVPRCRB1.86B.0016.D04.1705030402 05/03/2017
kernel: RIP: 0010:hugetlbfs_fill_super+0xb4/0x1a0
kernel: Code: 48 8b 3b e8 3e c6 ed ff 48 85 c0 48 89 45 20 0f 84 d6 00 00 00 48 b8 ff ff ff ff ff ff ff 7f 4c 89 e7 49 89 44 24 20 48 8b 03 <8b> 48 28 b8 00 10 00 00 48 d3 e0 49 89 44 24 18 48 8b 03 8b 40 28
kernel: RSP: 0018:ffffbe9960fcbd48 EFLAGS: 00010246
kernel: RAX: 0000000000000000 RBX: ffff9af5272ae780 RCX: 0000000000372004
kernel: RDX: ffffffffffffffff RSI: ffffffffffffffff RDI: ffff9af555e9b000
kernel: RBP: ffff9af52ee66b00 R08: 0000000000000040 R09: 0000000000370004
kernel: R10: ffffbe9960fcbd48 R11: 0000000000000040 R12: ffff9af555e9b000
kernel: R13: ffffffffa66b86c0 R14: ffff9af507d2f400 R15: ffff9af507d2f400
kernel: FS: 00007ffbc0ba4740(0000) GS:ffff9b0bd7000000(0000) knlGS:0000000000000000
kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kernel: CR2: 0000000000000028 CR3: 00000001b1ee0000 CR4: 00000000001506f0
kernel: Call Trace:
kernel: <TASK>
kernel: ? __die_body+0x1a/0x60
kernel: ? page_fault_oops+0x16f/0x4a0
kernel: ? search_bpf_extables+0x65/0x70
kernel: ? fixup_exception+0x22/0x310
kernel: ? exc_page_fault+0x69/0x150
kernel: ? asm_exc_page_fault+0x22/0x30
kernel: ? __pfx_hugetlbfs_fill_super+0x10/0x10
kernel: ? hugetlbfs_fill_super+0xb4/0x1a0
kernel: ? hugetlbfs_fill_super+0x28/0x1a0
kernel: ? __pfx_hugetlbfs_fill_super+0x10/0x10
kernel: vfs_get_super+0x40/0xa0
kernel: ? __pfx_bpf_lsm_capable+0x10/0x10
kernel: vfs_get_tree+0x25/0xd0
kernel: vfs_cmd_create+0x64/0xe0
kernel: __x64_sys_fsconfig+0x395/0x410
kernel: do_syscall_64+0x80/0x160
kernel: ? syscall_exit_to_user_mode+0x82/0x240
kernel: ? do_syscall_64+0x8d/0x160
kernel: ? syscall_exit_to_user_mode+0x82/0x240
kernel: ? do_syscall_64+0x8d/0x160
kernel: ? exc_page_fault+0x69/0x150
kernel: entry_SYSCALL_64_after_hwframe+0x6e/0x76
kernel: RIP: 0033:0x7ffbc0cb87c9
kernel: Code: 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 97 96 0d 00 f7 d8 64 89 01 48
kernel: RSP: 002b:00007ffc29d2f388 EFLAGS: 00000206 ORIG_RAX: 00000000000001af
kernel: RAX: fffffffffff
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-03
In the Linux kernel, the following vulnerability has been resolved:
ceph: prevent use-after-free in encode_cap_msg()
In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was
caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This
implies before the refcount could be increment here, it was freed.
In same file, in "handle_cap_grant()" refcount is decremented by this
line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race
occurred and resource was freed by the latter line before the former
line could increment it.
encode_cap_msg() is called by __send_cap() and __send_cap() is called by
ceph_check_caps() after calling __prep_cap(). __prep_cap() is where
arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where
the refcount must be increased to prevent "use after free" error.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-04-03
In the Linux kernel, the following vulnerability has been resolved:
net: stmmac: protect updates of 64-bit statistics counters
As explained by a comment in <linux/u64_stats_sync.h>, write side of struct
u64_stats_sync must ensure mutual exclusion, or one seqcount update could
be lost on 32-bit platforms, thus blocking readers forever. Such lockups
have been observed in real world after stmmac_xmit() on one CPU raced with
stmmac_napi_poll_tx() on another CPU.
To fix the issue without introducing a new lock, split the statics into
three parts:
1. fields updated only under the tx queue lock,
2. fields updated only during NAPI poll,
3. fields updated only from interrupt context,
Updates to fields in the first two groups are already serialized through
other locks. It is sufficient to split the existing struct u64_stats_sync
so that each group has its own.
Note that tx_set_ic_bit is updated from both contexts. Split this counter
so that each context gets its own, and calculate their sum to get the total
value in stmmac_get_ethtool_stats().
For the third group, multiple interrupts may be processed by different CPUs
at the same time, but interrupts on the same CPU will not nest. Move fields
from this group to a newly created per-cpu struct stmmac_pcpu_stats.
CVSS Score
6.5
EPSS Score
0.001
Published
2024-04-03
In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: Fix circular locking dependency
The rule inside kvm enforces that the vcpu->mutex is taken *inside*
kvm->lock. The rule is violated by the pkvm_create_hyp_vm() which acquires
the kvm->lock while already holding the vcpu->mutex lock from
kvm_vcpu_ioctl(). Avoid the circular locking dependency altogether by
protecting the hyp vm handle with the config_lock, much like we already
do for other forms of VM-scoped data.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-03
In the Linux kernel, the following vulnerability has been resolved:
smb: Fix regression in writes when non-standard maximum write size negotiated
The conversion to netfs in the 6.3 kernel caused a regression when
maximum write size is set by the server to an unexpected value which is
not a multiple of 4096 (similarly if the user overrides the maximum
write size by setting mount parm "wsize", but sets it to a value that
is not a multiple of 4096). When negotiated write size is not a
multiple of 4096 the netfs code can skip the end of the final
page when doing large sequential writes, causing data corruption.
This section of code is being rewritten/removed due to a large
netfs change, but until that point (ie for the 6.3 kernel until now)
we can not support non-standard maximum write sizes.
Add a warning if a user specifies a wsize on mount that is not
a multiple of 4096 (and round down), also add a change where we
round down the maximum write size if the server negotiates a value
that is not a multiple of 4096 (we also have to check to make sure that
we do not round it down to zero).
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-03
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: mvm: fix a crash when we run out of stations
A DoS tool that injects loads of authentication frames made our AP
crash. The iwl_mvm_is_dup() function couldn't find the per-queue
dup_data which was not allocated.
The root cause for that is that we ran out of stations in the firmware
and we didn't really add the station to the firmware, yet we didn't
return an error to mac80211.
Mac80211 was thinking that we have the station and because of that,
sta_info::uploaded was set to 1. This allowed
ieee80211_find_sta_by_ifaddr() to return a valid station object, but
that ieee80211_sta didn't have any iwl_mvm_sta object initialized and
that caused the crash mentioned earlier when we got Rx on that station.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-03
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: fix double-free bug
The storage for the TLV PC register data wasn't done like all
the other storage in the drv->fw area, which is cleared at the
end of deallocation. Therefore, the freeing must also be done
differently, explicitly NULL'ing it out after the free, since
otherwise there's a nasty double-free bug here if a file fails
to load after this has been parsed, and we get another free
later (e.g. because no other file exists.) Fix that by adding
the missing NULL assignment.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-04-03
In the Linux kernel, the following vulnerability has been resolved:
crypto: ccp - Fix null pointer dereference in __sev_platform_shutdown_locked
The SEV platform device can be shutdown with a null psp_master,
e.g., using DEBUG_TEST_DRIVER_REMOVE. Found using KASAN:
[ 137.148210] ccp 0000:23:00.1: enabling device (0000 -> 0002)
[ 137.162647] ccp 0000:23:00.1: no command queues available
[ 137.170598] ccp 0000:23:00.1: sev enabled
[ 137.174645] ccp 0000:23:00.1: psp enabled
[ 137.178890] general protection fault, probably for non-canonical address 0xdffffc000000001e: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN NOPTI
[ 137.182693] KASAN: null-ptr-deref in range [0x00000000000000f0-0x00000000000000f7]
[ 137.182693] CPU: 93 PID: 1 Comm: swapper/0 Not tainted 6.8.0-rc1+ #311
[ 137.182693] RIP: 0010:__sev_platform_shutdown_locked+0x51/0x180
[ 137.182693] Code: 08 80 3c 08 00 0f 85 0e 01 00 00 48 8b 1d 67 b6 01 08 48 b8 00 00 00 00 00 fc ff df 48 8d bb f0 00 00 00 48 89 f9 48 c1 e9 03 <80> 3c 01 00 0f 85 fe 00 00 00 48 8b 9b f0 00 00 00 48 85 db 74 2c
[ 137.182693] RSP: 0018:ffffc900000cf9b0 EFLAGS: 00010216
[ 137.182693] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 000000000000001e
[ 137.182693] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 00000000000000f0
[ 137.182693] RBP: ffffc900000cf9c8 R08: 0000000000000000 R09: fffffbfff58f5a66
[ 137.182693] R10: ffffc900000cf9c8 R11: ffffffffac7ad32f R12: ffff8881e5052c28
[ 137.182693] R13: ffff8881e5052c28 R14: ffff8881758e43e8 R15: ffffffffac64abf8
[ 137.182693] FS: 0000000000000000(0000) GS:ffff889de7000000(0000) knlGS:0000000000000000
[ 137.182693] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 137.182693] CR2: 0000000000000000 CR3: 0000001cf7c7e000 CR4: 0000000000350ef0
[ 137.182693] Call Trace:
[ 137.182693] <TASK>
[ 137.182693] ? show_regs+0x6c/0x80
[ 137.182693] ? __die_body+0x24/0x70
[ 137.182693] ? die_addr+0x4b/0x80
[ 137.182693] ? exc_general_protection+0x126/0x230
[ 137.182693] ? asm_exc_general_protection+0x2b/0x30
[ 137.182693] ? __sev_platform_shutdown_locked+0x51/0x180
[ 137.182693] sev_firmware_shutdown.isra.0+0x1e/0x80
[ 137.182693] sev_dev_destroy+0x49/0x100
[ 137.182693] psp_dev_destroy+0x47/0xb0
[ 137.182693] sp_destroy+0xbb/0x240
[ 137.182693] sp_pci_remove+0x45/0x60
[ 137.182693] pci_device_remove+0xaa/0x1d0
[ 137.182693] device_remove+0xc7/0x170
[ 137.182693] really_probe+0x374/0xbe0
[ 137.182693] ? srso_return_thunk+0x5/0x5f
[ 137.182693] __driver_probe_device+0x199/0x460
[ 137.182693] driver_probe_device+0x4e/0xd0
[ 137.182693] __driver_attach+0x191/0x3d0
[ 137.182693] ? __pfx___driver_attach+0x10/0x10
[ 137.182693] bus_for_each_dev+0x100/0x190
[ 137.182693] ? __pfx_bus_for_each_dev+0x10/0x10
[ 137.182693] ? __kasan_check_read+0x15/0x20
[ 137.182693] ? srso_return_thunk+0x5/0x5f
[ 137.182693] ? _raw_spin_unlock+0x27/0x50
[ 137.182693] driver_attach+0x41/0x60
[ 137.182693] bus_add_driver+0x2a8/0x580
[ 137.182693] driver_register+0x141/0x480
[ 137.182693] __pci_register_driver+0x1d6/0x2a0
[ 137.182693] ? srso_return_thunk+0x5/0x5f
[ 137.182693] ? esrt_sysfs_init+0x1cd/0x5d0
[ 137.182693] ? __pfx_sp_mod_init+0x10/0x10
[ 137.182693] sp_pci_init+0x22/0x30
[ 137.182693] sp_mod_init+0x14/0x30
[ 137.182693] ? __pfx_sp_mod_init+0x10/0x10
[ 137.182693] do_one_initcall+0xd1/0x470
[ 137.182693] ? __pfx_do_one_initcall+0x10/0x10
[ 137.182693] ? parameq+0x80/0xf0
[ 137.182693] ? srso_return_thunk+0x5/0x5f
[ 137.182693] ? __kmalloc+0x3b0/0x4e0
[ 137.182693] ? kernel_init_freeable+0x92d/0x1050
[ 137.182693] ? kasan_populate_vmalloc_pte+0x171/0x190
[ 137.182693] ? srso_return_thunk+0x5/0x5f
[ 137.182693] kernel_init_freeable+0xa64/0x1050
[ 137.182693] ? __pfx_kernel_init+0x10/0x10
[ 137.182693] kernel_init+0x24/0x160
[ 137.182693] ? __switch_to_asm+0x3e/0x70
[ 137.182693] ret_from_fork+0x40/0x80
[ 137.182693] ? __pfx_kernel_init+0x1
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-03
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix hang in nilfs_lookup_dirty_data_buffers()
Syzbot reported a hang issue in migrate_pages_batch() called by mbind()
and nilfs_lookup_dirty_data_buffers() called in the log writer of nilfs2.
While migrate_pages_batch() locks a folio and waits for the writeback to
complete, the log writer thread that should bring the writeback to
completion picks up the folio being written back in
nilfs_lookup_dirty_data_buffers() that it calls for subsequent log
creation and was trying to lock the folio. Thus causing a deadlock.
In the first place, it is unexpected that folios/pages in the middle of
writeback will be updated and become dirty. Nilfs2 adds a checksum to
verify the validity of the log being written and uses it for recovery at
mount, so data changes during writeback are suppressed. Since this is
broken, an unclean shutdown could potentially cause recovery to fail.
Investigation revealed that the root cause is that the wait for writeback
completion in nilfs_page_mkwrite() is conditional, and if the backing
device does not require stable writes, data may be modified without
waiting.
Fix these issues by making nilfs_page_mkwrite() wait for writeback to
finish regardless of the stable write requirement of the backing device.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-03
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix data corruption in dsync block recovery for small block sizes
The helper function nilfs_recovery_copy_block() of
nilfs_recovery_dsync_blocks(), which recovers data from logs created by
data sync writes during a mount after an unclean shutdown, incorrectly
calculates the on-page offset when copying repair data to the file's page
cache. In environments where the block size is smaller than the page
size, this flaw can cause data corruption and leak uninitialized memory
bytes during the recovery process.
Fix these issues by correcting this byte offset calculation on the page.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-03