Security Vulnerabilities
- CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
drm: Check output polling initialized before disabling
In drm_kms_helper_poll_disable() check if output polling
support is initialized before disabling polling. If not flag
this as a warning.
Additionally in drm_mode_config_helper_suspend() and
drm_mode_config_helper_resume() calls, that re the callers of these
functions, avoid invoking them if polling is not initialized.
For drivers like hyperv-drm, that do not initialize connector
polling, if suspend is called without this check, it leads to
suspend failure with following stack
[ 770.719392] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[ 770.720592] printk: Suspending console(s) (use no_console_suspend to debug)
[ 770.948823] ------------[ cut here ]------------
[ 770.948824] WARNING: CPU: 1 PID: 17197 at kernel/workqueue.c:3162 __flush_work.isra.0+0x212/0x230
[ 770.948831] Modules linked in: rfkill nft_counter xt_conntrack xt_owner udf nft_compat crc_itu_t nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables nfnetlink vfat fat mlx5_ib ib_uverbs ib_core mlx5_core intel_rapl_msr intel_rapl_common kvm_amd ccp mlxfw kvm psample hyperv_drm tls drm_shmem_helper drm_kms_helper irqbypass pcspkr syscopyarea sysfillrect sysimgblt hv_balloon hv_utils joydev drm fuse xfs libcrc32c pci_hyperv pci_hyperv_intf sr_mod sd_mod cdrom t10_pi sg hv_storvsc scsi_transport_fc hv_netvsc serio_raw hyperv_keyboard hid_hyperv crct10dif_pclmul crc32_pclmul crc32c_intel hv_vmbus ghash_clmulni_intel dm_mirror dm_region_hash dm_log dm_mod
[ 770.948863] CPU: 1 PID: 17197 Comm: systemd-sleep Not tainted 5.14.0-362.2.1.el9_3.x86_64 #1
[ 770.948865] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/09/2022
[ 770.948866] RIP: 0010:__flush_work.isra.0+0x212/0x230
[ 770.948869] Code: 8b 4d 00 4c 8b 45 08 89 ca 48 c1 e9 04 83 e2 08 83 e1 0f 83 ca 02 89 c8 48 0f ba 6d 00 03 e9 25 ff ff ff 0f 0b e9 4e ff ff ff <0f> 0b 45 31 ed e9 44 ff ff ff e8 8f 89 b2 00 66 66 2e 0f 1f 84 00
[ 770.948870] RSP: 0018:ffffaf4ac213fb10 EFLAGS: 00010246
[ 770.948871] RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8c992857
[ 770.948872] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff9aad82b00330
[ 770.948873] RBP: ffff9aad82b00330 R08: 0000000000000000 R09: ffff9aad87ee3d10
[ 770.948874] R10: 0000000000000200 R11: 0000000000000000 R12: ffff9aad82b00330
[ 770.948874] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
[ 770.948875] FS: 00007ff1b2f6bb40(0000) GS:ffff9aaf37d00000(0000) knlGS:0000000000000000
[ 770.948878] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 770.948878] CR2: 0000555f345cb666 CR3: 00000001462dc005 CR4: 0000000000370ee0
[ 770.948879] Call Trace:
[ 770.948880] <TASK>
[ 770.948881] ? show_trace_log_lvl+0x1c4/0x2df
[ 770.948884] ? show_trace_log_lvl+0x1c4/0x2df
[ 770.948886] ? __cancel_work_timer+0x103/0x190
[ 770.948887] ? __flush_work.isra.0+0x212/0x230
[ 770.948889] ? __warn+0x81/0x110
[ 770.948891] ? __flush_work.isra.0+0x212/0x230
[ 770.948892] ? report_bug+0x10a/0x140
[ 770.948895] ? handle_bug+0x3c/0x70
[ 770.948898] ? exc_invalid_op+0x14/0x70
[ 770.948899] ? asm_exc_invalid_op+0x16/0x20
[ 770.948903] ? __flush_work.isra.0+0x212/0x230
[ 770.948905] __cancel_work_timer+0x103/0x190
[ 770.948907] ? _raw_spin_unlock_irqrestore+0xa/0x30
[ 770.948910] drm_kms_helper_poll_disable+0x1e/0x40 [drm_kms_helper]
[ 770.948923] drm_mode_config_helper_suspend+0x1c/0x80 [drm_kms_helper]
[ 770.948933] ? __pfx_vmbus_suspend+0x10/0x10 [hv_vmbus]
[ 770.948942] hyperv_vmbus_suspend+0x17/0x40 [hyperv_drm]
[ 770.948944] ? __pfx_vmbus_suspend+0x10/0x10 [hv_vmbus]
[ 770.948951] dpm_run_callback+0x4c/0x140
[ 770.948954] __device_suspend_noir
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
rcu/nocb: Fix WARN_ON_ONCE() in the rcu_nocb_bypass_lock()
For the kernels built with CONFIG_RCU_NOCB_CPU_DEFAULT_ALL=y and
CONFIG_RCU_LAZY=y, the following scenarios will trigger WARN_ON_ONCE()
in the rcu_nocb_bypass_lock() and rcu_nocb_wait_contended() functions:
CPU2 CPU11
kthread
rcu_nocb_cb_kthread ksys_write
rcu_do_batch vfs_write
rcu_torture_timer_cb proc_sys_write
__kmem_cache_free proc_sys_call_handler
kmemleak_free drop_caches_sysctl_handler
delete_object_full drop_slab
__delete_object shrink_slab
put_object lazy_rcu_shrink_scan
call_rcu rcu_nocb_flush_bypass
__call_rcu_commn rcu_nocb_bypass_lock
raw_spin_trylock(&rdp->nocb_bypass_lock) fail
atomic_inc(&rdp->nocb_lock_contended);
rcu_nocb_wait_contended WARN_ON_ONCE(smp_processor_id() != rdp->cpu);
WARN_ON_ONCE(atomic_read(&rdp->nocb_lock_contended)) |
|_ _ _ _ _ _ _ _ _ _same rdp and rdp->cpu != 11_ _ _ _ _ _ _ _ _ __|
Reproduce this bug with "echo 3 > /proc/sys/vm/drop_caches".
This commit therefore uses rcu_nocb_try_flush_bypass() instead of
rcu_nocb_flush_bypass() in lazy_rcu_shrink_scan(). If the nocb_bypass
queue is being flushed, then rcu_nocb_try_flush_bypass will return
directly.
In the Linux kernel, the following vulnerability has been resolved:
sysv: don't call sb_bread() with pointers_lock held
syzbot is reporting sleep in atomic context in SysV filesystem [1], for
sb_bread() is called with rw_spinlock held.
A "write_lock(&pointers_lock) => read_lock(&pointers_lock) deadlock" bug
and a "sb_bread() with write_lock(&pointers_lock)" bug were introduced by
"Replace BKL for chain locking with sysvfs-private rwlock" in Linux 2.5.12.
Then, "[PATCH] err1-40: sysvfs locking fix" in Linux 2.6.8 fixed the
former bug by moving pointers_lock lock to the callers, but instead
introduced a "sb_bread() with read_lock(&pointers_lock)" bug (which made
this problem easier to hit).
Al Viro suggested that why not to do like get_branch()/get_block()/
find_shared() in Minix filesystem does. And doing like that is almost a
revert of "[PATCH] err1-40: sysvfs locking fix" except that get_branch()
from with find_shared() is called without write_lock(&pointers_lock).
In the Linux kernel, the following vulnerability has been resolved:
dma-buf: Fix NULL pointer dereference in sanitycheck()
If due to a memory allocation failure mock_chain() returns NULL, it is
passed to dma_fence_enable_sw_signaling() resulting in NULL pointer
dereference there.
Call dma_fence_enable_sw_signaling() only if mock_chain() succeeds.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
s390/bpf: Fix bpf_plt pointer arithmetic
Kui-Feng Lee reported a crash on s390x triggered by the
dummy_st_ops/dummy_init_ptr_arg test [1]:
[<0000000000000002>] 0x2
[<00000000009d5cde>] bpf_struct_ops_test_run+0x156/0x250
[<000000000033145a>] __sys_bpf+0xa1a/0xd00
[<00000000003319dc>] __s390x_sys_bpf+0x44/0x50
[<0000000000c4382c>] __do_syscall+0x244/0x300
[<0000000000c59a40>] system_call+0x70/0x98
This is caused by GCC moving memcpy() after assignments in
bpf_jit_plt(), resulting in NULL pointers being written instead of
the return and the target addresses.
Looking at the GCC internals, the reordering is allowed because the
alias analysis thinks that the memcpy() destination and the assignments'
left-hand-sides are based on different objects: new_plt and
bpf_plt_ret/bpf_plt_target respectively, and therefore they cannot
alias.
This is in turn due to a violation of the C standard:
When two pointers are subtracted, both shall point to elements of the
same array object, or one past the last element of the array object
...
From the C's perspective, bpf_plt_ret and bpf_plt are distinct objects
and cannot be subtracted. In the practical terms, doing so confuses the
GCC's alias analysis.
The code was written this way in order to let the C side know a few
offsets defined in the assembly. While nice, this is by no means
necessary. Fix the noncompliance by hardcoding these offsets.
[1] https://lore.kernel.org/bpf/c9923c1d-971d-4022-8dc8-1364e929d34c@gmail.com/
In the Linux kernel, the following vulnerability has been resolved:
net/rds: fix possible cp null dereference
cp might be null, calling cp->cp_conn would produce null dereference
[Simon Horman adds:]
Analysis:
* cp is a parameter of __rds_rdma_map and is not reassigned.
* The following call-sites pass a NULL cp argument to __rds_rdma_map()
- rds_get_mr()
- rds_get_mr_for_dest
* Prior to the code above, the following assumes that cp may be NULL
(which is indicative, but could itself be unnecessary)
trans_private = rs->rs_transport->get_mr(
sg, nents, rs, &mr->r_key, cp ? cp->cp_conn : NULL,
args->vec.addr, args->vec.bytes,
need_odp ? ODP_ZEROBASED : ODP_NOT_NEEDED);
* The code modified by this patch is guarded by IS_ERR(trans_private),
where trans_private is assigned as per the previous point in this analysis.
The only implementation of get_mr that I could locate is rds_ib_get_mr()
which can return an ERR_PTR if the conn (4th) argument is NULL.
* ret is set to PTR_ERR(trans_private).
rds_ib_get_mr can return ERR_PTR(-ENODEV) if the conn (4th) argument is NULL.
Thus ret may be -ENODEV in which case the code in question will execute.
Conclusion:
* cp may be NULL at the point where this patch adds a check;
this patch does seem to address a possible bug
In the Linux kernel, the following vulnerability has been resolved:
x86/bpf: Fix IP after emitting call depth accounting
Adjust the IP passed to `emit_patch` so it calculates the correct offset
for the CALL instruction if `x86_call_depth_emit_accounting` emits code.
Otherwise we will skip some instructions and most likely crash.
In the Linux kernel, the following vulnerability has been resolved:
selinux: avoid dereference of garbage after mount failure
In case kern_mount() fails and returns an error pointer return in the
error branch instead of continuing and dereferencing the error pointer.
While on it drop the never read static variable selinuxfs_mount.
In the Linux kernel, the following vulnerability has been resolved:
bpf: Protect against int overflow for stack access size
This patch re-introduces protection against the size of access to stack
memory being negative; the access size can appear negative as a result
of overflowing its signed int representation. This should not actually
happen, as there are other protections along the way, but we should
protect against it anyway. One code path was missing such protections
(fixed in the previous patch in the series), causing out-of-bounds array
accesses in check_stack_range_initialized(). This patch causes the
verification of a program with such a non-sensical access size to fail.
This check used to exist in a more indirect way, but was inadvertendly
removed in a833a17aeac7.
In the Linux kernel, the following vulnerability has been resolved:
mlxbf_gige: call request_irq() after NAPI initialized
The mlxbf_gige driver encounters a NULL pointer exception in
mlxbf_gige_open() when kdump is enabled. The sequence to reproduce
the exception is as follows:
a) enable kdump
b) trigger kdump via "echo c > /proc/sysrq-trigger"
c) kdump kernel executes
d) kdump kernel loads mlxbf_gige module
e) the mlxbf_gige module runs its open() as the
the "oob_net0" interface is brought up
f) mlxbf_gige module will experience an exception
during its open(), something like:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Mem abort info:
ESR = 0x0000000086000004
EC = 0x21: IABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x04: level 0 translation fault
user pgtable: 4k pages, 48-bit VAs, pgdp=00000000e29a4000
[0000000000000000] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 0000000086000004 [#1] SMP
CPU: 0 PID: 812 Comm: NetworkManager Tainted: G OE 5.15.0-1035-bluefield #37-Ubuntu
Hardware name: https://www.mellanox.com BlueField-3 SmartNIC Main Card/BlueField-3 SmartNIC Main Card, BIOS 4.6.0.13024 Jan 19 2024
pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : 0x0
lr : __napi_poll+0x40/0x230
sp : ffff800008003e00
x29: ffff800008003e00 x28: 0000000000000000 x27: 00000000ffffffff
x26: ffff000066027238 x25: ffff00007cedec00 x24: ffff800008003ec8
x23: 000000000000012c x22: ffff800008003eb7 x21: 0000000000000000
x20: 0000000000000001 x19: ffff000066027238 x18: 0000000000000000
x17: ffff578fcb450000 x16: ffffa870b083c7c0 x15: 0000aaab010441d0
x14: 0000000000000001 x13: 00726f7272655f65 x12: 6769675f6662786c
x11: 0000000000000000 x10: 0000000000000000 x9 : ffffa870b0842398
x8 : 0000000000000004 x7 : fe5a48b9069706ea x6 : 17fdb11fc84ae0d2
x5 : d94a82549d594f35 x4 : 0000000000000000 x3 : 0000000000400100
x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff000066027238
Call trace:
0x0
net_rx_action+0x178/0x360
__do_softirq+0x15c/0x428
__irq_exit_rcu+0xac/0xec
irq_exit+0x18/0x2c
handle_domain_irq+0x6c/0xa0
gic_handle_irq+0xec/0x1b0
call_on_irq_stack+0x20/0x2c
do_interrupt_handler+0x5c/0x70
el1_interrupt+0x30/0x50
el1h_64_irq_handler+0x18/0x2c
el1h_64_irq+0x7c/0x80
__setup_irq+0x4c0/0x950
request_threaded_irq+0xf4/0x1bc
mlxbf_gige_request_irqs+0x68/0x110 [mlxbf_gige]
mlxbf_gige_open+0x5c/0x170 [mlxbf_gige]
__dev_open+0x100/0x220
__dev_change_flags+0x16c/0x1f0
dev_change_flags+0x2c/0x70
do_setlink+0x220/0xa40
__rtnl_newlink+0x56c/0x8a0
rtnl_newlink+0x58/0x84
rtnetlink_rcv_msg+0x138/0x3c4
netlink_rcv_skb+0x64/0x130
rtnetlink_rcv+0x20/0x30
netlink_unicast+0x2ec/0x360
netlink_sendmsg+0x278/0x490
__sock_sendmsg+0x5c/0x6c
____sys_sendmsg+0x290/0x2d4
___sys_sendmsg+0x84/0xd0
__sys_sendmsg+0x70/0xd0
__arm64_sys_sendmsg+0x2c/0x40
invoke_syscall+0x78/0x100
el0_svc_common.constprop.0+0x54/0x184
do_el0_svc+0x30/0xac
el0_svc+0x48/0x160
el0t_64_sync_handler+0xa4/0x12c
el0t_64_sync+0x1a4/0x1a8
Code: bad PC value
---[ end trace 7d1c3f3bf9d81885 ]---
Kernel panic - not syncing: Oops: Fatal exception in interrupt
Kernel Offset: 0x2870a7a00000 from 0xffff800008000000
PHYS_OFFSET: 0x80000000
CPU features: 0x0,000005c1,a3332a5a
Memory Limit: none
---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]---
The exception happens because there is a pending RX interrupt before the
call to request_irq(RX IRQ) executes. Then, the RX IRQ handler fires
immediately after this request_irq() completes. The
---truncated---