| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix race setting file private on concurrent lseek using same fd
When doing concurrent lseek(2) system calls against the same file
descriptor, using multiple threads belonging to the same process, we have
a short time window where a race happens and can result in a memory leak.
The race happens like this:
1) A program opens a file descriptor for a file and then spawns two
threads (with the pthreads library for example), lets call them
task A and task B;
2) Task A calls lseek with SEEK_DATA or SEEK_HOLE and ends up at
file.c:find_desired_extent() while holding a read lock on the inode;
3) At the start of find_desired_extent(), it extracts the file's
private_data pointer into a local variable named 'private', which has
a value of NULL;
4) Task B also calls lseek with SEEK_DATA or SEEK_HOLE, locks the inode
in shared mode and enters file.c:find_desired_extent(), where it also
extracts file->private_data into its local variable 'private', which
has a NULL value;
5) Because it saw a NULL file private, task A allocates a private
structure and assigns to the file structure;
6) Task B also saw a NULL file private so it also allocates its own file
private and then assigns it to the same file structure, since both
tasks are using the same file descriptor.
At this point we leak the private structure allocated by task A.
Besides the memory leak, there's also the detail that both tasks end up
using the same cached state record in the private structure (struct
btrfs_file_private::llseek_cached_state), which can result in a
use-after-free problem since one task can free it while the other is
still using it (only one task took a reference count on it). Also, sharing
the cached state is not a good idea since it could result in incorrect
results in the future - right now it should not be a problem because it
end ups being used only in extent-io-tree.c:count_range_bits() where we do
range validation before using the cached state.
Fix this by protecting the private assignment and check of a file while
holding the inode's spinlock and keep track of the task that allocated
the private, so that it's used only by that task in order to prevent
user-after-free issues with the cached state record as well as potentially
using it incorrectly in the future. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: Require FMODE_WRITE for atomic write ioctls
The F2FS ioctls for starting and committing atomic writes check for
inode_owner_or_capable(), but this does not give LSMs like SELinux or
Landlock an opportunity to deny the write access - if the caller's FSUID
matches the inode's UID, inode_owner_or_capable() immediately returns true.
There are scenarios where LSMs want to deny a process the ability to write
particular files, even files that the FSUID of the process owns; but this
can currently partially be bypassed using atomic write ioctls in two ways:
- F2FS_IOC_START_ATOMIC_REPLACE + F2FS_IOC_COMMIT_ATOMIC_WRITE can
truncate an inode to size 0
- F2FS_IOC_START_ATOMIC_WRITE + F2FS_IOC_ABORT_ATOMIC_WRITE can revert
changes another process concurrently made to a file
Fix it by requiring FMODE_WRITE for these operations, just like for
F2FS_IOC_MOVE_RANGE. Since any legitimate caller should only be using these
ioctls when intending to write into the file, that seems unlikely to break
anything. |
| In the Linux kernel, the following vulnerability has been resolved:
padata: use integer wrap around to prevent deadlock on seq_nr overflow
When submitting more than 2^32 padata objects to padata_do_serial, the
current sorting implementation incorrectly sorts padata objects with
overflowed seq_nr, causing them to be placed before existing objects in
the reorder list. This leads to a deadlock in the serialization process
as padata_find_next cannot match padata->seq_nr and pd->processed
because the padata instance with overflowed seq_nr will be selected
next.
To fix this, we use an unsigned integer wrap around to correctly sort
padata objects in scenarios with integer overflow. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: iaa - Fix potential use after free bug
The free_device_compression_mode(iaa_device, device_mode) function frees
"device_mode" but it iss passed to iaa_compression_modes[i]->free() a few
lines later resulting in a use after free.
The good news is that, so far as I can tell, nothing implements the
->free() function and the use after free happens in dead code. But, with
this fix, when something does implement it, we'll be ready. :) |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: hisilicon/qm - inject error before stopping queue
The master ooo cannot be completely closed when the
accelerator core reports memory error. Therefore, the driver
needs to inject the qm error to close the master ooo. Currently,
the qm error is injected after stopping queue, memory may be
released immediately after stopping queue, causing the device to
access the released memory. Therefore, error is injected to close master
ooo before stopping queue to ensure that the device does not access
the released memory. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to wait dio completion
It should wait all existing dio write IOs before block removal,
otherwise, previous direct write IO may overwrite data in the
block which may be reused by other inode. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: use work queue to process beacon tx event
Commit 3a415daa3e8b ("wifi: ath11k: add P2P IE in beacon template")
from Feb 28, 2024 (linux-next), leads to the following Smatch static
checker warning:
drivers/net/wireless/ath/ath11k/wmi.c:1742 ath11k_wmi_p2p_go_bcn_ie()
warn: sleeping in atomic context
The reason is that ath11k_bcn_tx_status_event() will directly call might
sleep function ath11k_wmi_cmd_send() during RCU read-side critical
sections. The call trace is like:
ath11k_bcn_tx_status_event()
-> rcu_read_lock()
-> ath11k_mac_bcn_tx_event()
-> ath11k_mac_setup_bcn_tmpl()
……
-> ath11k_wmi_bcn_tmpl()
-> ath11k_wmi_cmd_send()
-> rcu_read_unlock()
Commit 886433a98425 ("ath11k: add support for BSS color change") added the
ath11k_mac_bcn_tx_event(), commit 01e782c89108 ("ath11k: fix warning
of RCU usage for ath11k_mac_get_arvif_by_vdev_id()") added the RCU lock
to avoid warning but also introduced this BUG.
Use work queue to avoid directly calling ath11k_mac_bcn_tx_event()
during RCU critical sections. No need to worry about the deletion of vif
because cancel_work_sync() will drop the work if it doesn't start or
block vif deletion until the running work is done.
Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.30 |
| In the Linux kernel, the following vulnerability has been resolved:
jfs: fix out-of-bounds in dbNextAG() and diAlloc()
In dbNextAG() , there is no check for the case where bmp->db_numag is
greater or same than MAXAG due to a polluted image, which causes an
out-of-bounds. Therefore, a bounds check should be added in dbMount().
And in dbNextAG(), a check for the case where agpref is greater than
bmp->db_numag should be added, so an out-of-bounds exception should be
prevented.
Additionally, a check for the case where agno is greater or same than
MAXAG should be added in diAlloc() to prevent out-of-bounds. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw89: remove unused C2H event ID RTW89_MAC_C2H_FUNC_READ_WOW_CAM to prevent out-of-bounds reading
The handler of firmware C2H event RTW89_MAC_C2H_FUNC_READ_WOW_CAM isn't
implemented, but driver expects number of handlers is
NUM_OF_RTW89_MAC_C2H_FUNC_WOW causing out-of-bounds access. Fix it by
removing ID.
Addresses-Coverity-ID: 1598775 ("Out-of-bounds read") |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7996: use hweight16 to get correct tx antenna
The chainmask is u16 so using hweight8 cannot get correct tx_ant.
Without this patch, the tx_ant of band 2 would be -1 and lead to the
following issue:
BUG: KASAN: stack-out-of-bounds in mt7996_mcu_add_sta+0x12e0/0x16e0 [mt7996e] |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: wilc1000: fix potential RCU dereference issue in wilc_parse_join_bss_param
In the `wilc_parse_join_bss_param` function, the TSF field of the `ies`
structure is accessed after the RCU read-side critical section is
unlocked. According to RCU usage rules, this is illegal. Reusing this
pointer can lead to unpredictable behavior, including accessing memory
that has been updated or causing use-after-free issues.
This possible bug was identified using a static analysis tool developed
by myself, specifically designed to detect RCU-related issues.
To address this, the TSF value is now stored in a local variable
`ies_tsf` before the RCU lock is released. The `param->tsf_lo` field is
then assigned using this local variable, ensuring that the TSF value is
safely accessed. |
| In the Linux kernel, the following vulnerability has been resolved:
block, bfq: fix possible UAF for bfqq->bic with merge chain
1) initial state, three tasks:
Process 1 Process 2 Process 3
(BIC1) (BIC2) (BIC3)
| Λ | Λ | Λ
| | | | | |
V | V | V |
bfqq1 bfqq2 bfqq3
process ref: 1 1 1
2) bfqq1 merged to bfqq2:
Process 1 Process 2 Process 3
(BIC1) (BIC2) (BIC3)
| | | Λ
\--------------\| | |
V V |
bfqq1--------->bfqq2 bfqq3
process ref: 0 2 1
3) bfqq2 merged to bfqq3:
Process 1 Process 2 Process 3
(BIC1) (BIC2) (BIC3)
here -> Λ | |
\--------------\ \-------------\|
V V
bfqq1--------->bfqq2---------->bfqq3
process ref: 0 1 3
In this case, IO from Process 1 will get bfqq2 from BIC1 first, and then
get bfqq3 through merge chain, and finially handle IO by bfqq3.
Howerver, current code will think bfqq2 is owned by BIC1, like initial
state, and set bfqq2->bic to BIC1.
bfq_insert_request
-> by Process 1
bfqq = bfq_init_rq(rq)
bfqq = bfq_get_bfqq_handle_split
bfqq = bic_to_bfqq
-> get bfqq2 from BIC1
bfqq->ref++
rq->elv.priv[0] = bic
rq->elv.priv[1] = bfqq
if (bfqq_process_refs(bfqq) == 1)
bfqq->bic = bic
-> record BIC1 to bfqq2
__bfq_insert_request
new_bfqq = bfq_setup_cooperator
-> get bfqq3 from bfqq2->new_bfqq
bfqq_request_freed(bfqq)
new_bfqq->ref++
rq->elv.priv[1] = new_bfqq
-> handle IO by bfqq3
Fix the problem by checking bfqq is from merge chain fist. And this
might fix a following problem reported by our syzkaller(unreproducible):
==================================================================
BUG: KASAN: slab-use-after-free in bfq_do_early_stable_merge block/bfq-iosched.c:5692 [inline]
BUG: KASAN: slab-use-after-free in bfq_do_or_sched_stable_merge block/bfq-iosched.c:5805 [inline]
BUG: KASAN: slab-use-after-free in bfq_get_queue+0x25b0/0x2610 block/bfq-iosched.c:5889
Write of size 1 at addr ffff888123839eb8 by task kworker/0:1H/18595
CPU: 0 PID: 18595 Comm: kworker/0:1H Tainted: G L 6.6.0-07439-gba2303cacfda #6
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Workqueue: kblockd blk_mq_requeue_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x91/0xf0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0x10d/0x610 mm/kasan/report.c:475
kasan_report+0x8e/0xc0 mm/kasan/report.c:588
bfq_do_early_stable_merge block/bfq-iosched.c:5692 [inline]
bfq_do_or_sched_stable_merge block/bfq-iosched.c:5805 [inline]
bfq_get_queue+0x25b0/0x2610 block/bfq-iosched.c:5889
bfq_get_bfqq_handle_split+0x169/0x5d0 block/bfq-iosched.c:6757
bfq_init_rq block/bfq-iosched.c:6876 [inline]
bfq_insert_request block/bfq-iosched.c:6254 [inline]
bfq_insert_requests+0x1112/0x5cf0 block/bfq-iosched.c:6304
blk_mq_insert_request+0x290/0x8d0 block/blk-mq.c:2593
blk_mq_requeue_work+0x6bc/0xa70 block/blk-mq.c:1502
process_one_work kernel/workqueue.c:2627 [inline]
process_scheduled_works+0x432/0x13f0 kernel/workqueue.c:2700
worker_thread+0x6f2/0x1160 kernel/workqueue.c:2781
kthread+0x33c/0x440 kernel/kthread.c:388
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:305
</TASK>
Allocated by task 20776:
kasan_save_stack+0x20/0x40 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
__kasan_slab_alloc+0x87/0x90 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook mm/slab.h:763 [inline]
slab_alloc_node mm/slub.c:3458 [inline]
kmem_cache_alloc_node+0x1a4/0x6f0 mm/slub.c:3503
ioc_create_icq block/blk-ioc.c:370 [inline]
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
bpf, lsm: Add check for BPF LSM return value
A bpf prog returning a positive number attached to file_alloc_security
hook makes kernel panic.
This happens because file system can not filter out the positive number
returned by the LSM prog using IS_ERR, and misinterprets this positive
number as a file pointer.
Given that hook file_alloc_security never returned positive number
before the introduction of BPF LSM, and other BPF LSM hooks may
encounter similar issues, this patch adds LSM return value check
in verifier, to ensure no unexpected value is returned. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fail verification for sign-extension of packet data/data_end/data_meta
syzbot reported a kernel crash due to
commit 1f1e864b6555 ("bpf: Handle sign-extenstin ctx member accesses").
The reason is due to sign-extension of 32-bit load for
packet data/data_end/data_meta uapi field.
The original code looks like:
r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */
r3 = *(u32 *)(r1 + 80) /* load __sk_buff->data_end */
r0 = r2
r0 += 8
if r3 > r0 goto +1
...
Note that __sk_buff->data load has 32-bit sign extension.
After verification and convert_ctx_accesses(), the final asm code looks like:
r2 = *(u64 *)(r1 +208)
r2 = (s32)r2
r3 = *(u64 *)(r1 +80)
r0 = r2
r0 += 8
if r3 > r0 goto pc+1
...
Note that 'r2 = (s32)r2' may make the kernel __sk_buff->data address invalid
which may cause runtime failure.
Currently, in C code, typically we have
void *data = (void *)(long)skb->data;
void *data_end = (void *)(long)skb->data_end;
...
and it will generate
r2 = *(u64 *)(r1 +208)
r3 = *(u64 *)(r1 +80)
r0 = r2
r0 += 8
if r3 > r0 goto pc+1
If we allow sign-extension,
void *data = (void *)(long)(int)skb->data;
void *data_end = (void *)(long)skb->data_end;
...
the generated code looks like
r2 = *(u64 *)(r1 +208)
r2 <<= 32
r2 s>>= 32
r3 = *(u64 *)(r1 +80)
r0 = r2
r0 += 8
if r3 > r0 goto pc+1
and this will cause verification failure since "r2 <<= 32" is not allowed
as "r2" is a packet pointer.
To fix this issue for case
r2 = *(s32 *)(r1 + 76) /* load __sk_buff->data */
this patch added additional checking in is_valid_access() callback
function for packet data/data_end/data_meta access. If those accesses
are with sign-extenstion, the verification will fail.
[1] https://lore.kernel.org/bpf/000000000000c90eee061d236d37@google.com/ |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/iwcm: Fix WARNING:at_kernel/workqueue.c:#check_flush_dependency
In the commit aee2424246f9 ("RDMA/iwcm: Fix a use-after-free related to
destroying CM IDs"), the function flush_workqueue is invoked to flush the
work queue iwcm_wq.
But at that time, the work queue iwcm_wq was created via the function
alloc_ordered_workqueue without the flag WQ_MEM_RECLAIM.
Because the current process is trying to flush the whole iwcm_wq, if
iwcm_wq doesn't have the flag WQ_MEM_RECLAIM, verify that the current
process is not reclaiming memory or running on a workqueue which doesn't
have the flag WQ_MEM_RECLAIM as that can break forward-progress guarantee
leading to a deadlock.
The call trace is as below:
[ 125.350876][ T1430] Call Trace:
[ 125.356281][ T1430] <TASK>
[ 125.361285][ T1430] ? __warn (kernel/panic.c:693)
[ 125.367640][ T1430] ? check_flush_dependency (kernel/workqueue.c:3706 (discriminator 9))
[ 125.375689][ T1430] ? report_bug (lib/bug.c:180 lib/bug.c:219)
[ 125.382505][ T1430] ? handle_bug (arch/x86/kernel/traps.c:239)
[ 125.388987][ T1430] ? exc_invalid_op (arch/x86/kernel/traps.c:260 (discriminator 1))
[ 125.395831][ T1430] ? asm_exc_invalid_op (arch/x86/include/asm/idtentry.h:621)
[ 125.403125][ T1430] ? check_flush_dependency (kernel/workqueue.c:3706 (discriminator 9))
[ 125.410984][ T1430] ? check_flush_dependency (kernel/workqueue.c:3706 (discriminator 9))
[ 125.418764][ T1430] __flush_workqueue (kernel/workqueue.c:3970)
[ 125.426021][ T1430] ? __pfx___might_resched (kernel/sched/core.c:10151)
[ 125.433431][ T1430] ? destroy_cm_id (drivers/infiniband/core/iwcm.c:375) iw_cm
[ 125.441209][ T1430] ? __pfx___flush_workqueue (kernel/workqueue.c:3910)
[ 125.473900][ T1430] ? _raw_spin_lock_irqsave (arch/x86/include/asm/atomic.h:107 include/linux/atomic/atomic-arch-fallback.h:2170 include/linux/atomic/atomic-instrumented.h:1302 include/asm-generic/qspinlock.h:111 include/linux/spinlock.h:187 include/linux/spinlock_api_smp.h:111 kernel/locking/spinlock.c:162)
[ 125.473909][ T1430] ? __pfx__raw_spin_lock_irqsave (kernel/locking/spinlock.c:161)
[ 125.482537][ T1430] _destroy_id (drivers/infiniband/core/cma.c:2044) rdma_cm
[ 125.495072][ T1430] nvme_rdma_free_queue (drivers/nvme/host/rdma.c:656 drivers/nvme/host/rdma.c:650) nvme_rdma
[ 125.505827][ T1430] nvme_rdma_reset_ctrl_work (drivers/nvme/host/rdma.c:2180) nvme_rdma
[ 125.505831][ T1430] process_one_work (kernel/workqueue.c:3231)
[ 125.515122][ T1430] worker_thread (kernel/workqueue.c:3306 kernel/workqueue.c:3393)
[ 125.515127][ T1430] ? __pfx_worker_thread (kernel/workqueue.c:3339)
[ 125.531837][ T1430] kthread (kernel/kthread.c:389)
[ 125.539864][ T1430] ? __pfx_kthread (kernel/kthread.c:342)
[ 125.550628][ T1430] ret_from_fork (arch/x86/kernel/process.c:147)
[ 125.558840][ T1430] ? __pfx_kthread (kernel/kthread.c:342)
[ 125.558844][ T1430] ret_from_fork_asm (arch/x86/entry/entry_64.S:257)
[ 125.566487][ T1430] </TASK>
[ 125.566488][ T1430] ---[ end trace 0000000000000000 ]--- |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/rtrs-clt: Reset cid to con_num - 1 to stay in bounds
In the function init_conns(), after the create_con() and create_cm() for
loop if something fails. In the cleanup for loop after the destroy tag, we
access out of bound memory because cid is set to clt_path->s.con_num.
This commits resets the cid to clt_path->s.con_num - 1, to stay in bounds
in the cleanup loop later. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: get rid of online repaire on corrupted directory
syzbot reports a f2fs bug as below:
kernel BUG at fs/f2fs/inode.c:896!
RIP: 0010:f2fs_evict_inode+0x1598/0x15c0 fs/f2fs/inode.c:896
Call Trace:
evict+0x532/0x950 fs/inode.c:704
dispose_list fs/inode.c:747 [inline]
evict_inodes+0x5f9/0x690 fs/inode.c:797
generic_shutdown_super+0x9d/0x2d0 fs/super.c:627
kill_block_super+0x44/0x90 fs/super.c:1696
kill_f2fs_super+0x344/0x690 fs/f2fs/super.c:4898
deactivate_locked_super+0xc4/0x130 fs/super.c:473
cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1373
task_work_run+0x24f/0x310 kernel/task_work.c:228
ptrace_notify+0x2d2/0x380 kernel/signal.c:2402
ptrace_report_syscall include/linux/ptrace.h:415 [inline]
ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline]
syscall_exit_work+0xc6/0x190 kernel/entry/common.c:173
syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline]
syscall_exit_to_user_mode+0x279/0x370 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0010:f2fs_evict_inode+0x1598/0x15c0 fs/f2fs/inode.c:896
Online repaire on corrupted directory in f2fs_lookup() can generate
dirty data/meta while racing w/ readonly remount, it may leave dirty
inode after filesystem becomes readonly, however, checkpoint() will
skips flushing dirty inode in a state of readonly mode, result in
above panic.
Let's get rid of online repaire in f2fs_lookup(), and leave the work
to fsck.f2fs. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: sd: Fix off-by-one error in sd_read_block_characteristics()
Ff the device returns page 0xb1 with length 8 (happens with qemu v2.x, for
example), sd_read_block_characteristics() may attempt an out-of-bounds
memory access when accessing the zoned field at offset 8. |
| In the Linux kernel, the following vulnerability has been resolved:
vfs: fix race between evice_inodes() and find_inode()&iput()
Hi, all
Recently I noticed a bug[1] in btrfs, after digged it into
and I believe it'a race in vfs.
Let's assume there's a inode (ie ino 261) with i_count 1 is
called by iput(), and there's a concurrent thread calling
generic_shutdown_super().
cpu0: cpu1:
iput() // i_count is 1
->spin_lock(inode)
->dec i_count to 0
->iput_final() generic_shutdown_super()
->__inode_add_lru() ->evict_inodes()
// cause some reason[2] ->if (atomic_read(inode->i_count)) continue;
// return before // inode 261 passed the above check
// list_lru_add_obj() // and then schedule out
->spin_unlock()
// note here: the inode 261
// was still at sb list and hash list,
// and I_FREEING|I_WILL_FREE was not been set
btrfs_iget()
// after some function calls
->find_inode()
// found the above inode 261
->spin_lock(inode)
// check I_FREEING|I_WILL_FREE
// and passed
->__iget()
->spin_unlock(inode) // schedule back
->spin_lock(inode)
// check (I_NEW|I_FREEING|I_WILL_FREE) flags,
// passed and set I_FREEING
iput() ->spin_unlock(inode)
->spin_lock(inode) ->evict()
// dec i_count to 0
->iput_final()
->spin_unlock()
->evict()
Now, we have two threads simultaneously evicting
the same inode, which may trigger the BUG(inode->i_state & I_CLEAR)
statement both within clear_inode() and iput().
To fix the bug, recheck the inode->i_count after holding i_lock.
Because in the most scenarios, the first check is valid, and
the overhead of spin_lock() can be reduced.
If there is any misunderstanding, please let me know, thanks.
[1]: https://lore.kernel.org/linux-btrfs/000000000000eabe1d0619c48986@google.com/
[2]: The reason might be 1. SB_ACTIVE was removed or 2. mapping_shrinkable()
return false when I reproduced the bug. |
| In the Linux kernel, the following vulnerability has been resolved:
icmp: change the order of rate limits
ICMP messages are ratelimited :
After the blamed commits, the two rate limiters are applied in this order:
1) host wide ratelimit (icmp_global_allow())
2) Per destination ratelimit (inetpeer based)
In order to avoid side-channels attacks, we need to apply
the per destination check first.
This patch makes the following change :
1) icmp_global_allow() checks if the host wide limit is reached.
But credits are not yet consumed. This is deferred to 3)
2) The per destination limit is checked/updated.
This might add a new node in inetpeer tree.
3) icmp_global_consume() consumes tokens if prior operations succeeded.
This means that host wide ratelimit is still effective
in keeping inetpeer tree small even under DDOS.
As a bonus, I removed icmp_global.lock as the fast path
can use a lock-free operation. |