| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| LibreDWG is a free C library to read and write DWG files. Prior to 0.14.8413, a crafted pre-R13 DWG can make `decode_preR13_entities()` in `src/decode.c` enter a nonterminating loop that allocates a new object each iteration. `decode_preR13` in `src/decode_r11.c` computes `size` from the raw file-controlled `entities_start` and `entities_end` header bounds; the callee clamps `end` to `dat->size` but never recalculates `size`. At `end` of input, `bit_read_RC` and `bit_read_RS` stop advancing `dat->byte`, the overflow guard fails because `end` equals `dat->size`, and the no-advance check compares against `oldpos` saved before the loop instead of the previous iteration. This leaves repeated allocation of `dwg->object` entries until allocation fails or the process is OOM-killed, not merely a constant-memory CPU hang. The defect remains after the clamping and no-progress changes associated with the earlier issue 1131. Applications and tools calling `dwg_read_file()` on untrusted files, including `dwg2dxf`, `dwgread` and `dwg2svg`, can suffer denial of service when a user or automated pipeline opens a malformed file; no attacker credentials are required. This issue is fixed in repository nightly version 0.14.8413. |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix possible infinite loop in fib6_select_path()
Found while auditing the same pattern Sashiko reported in
rt6_fill_node() [1]. Apply the same fix as
commit f8d8ce1b515a ("ipv6: fix possible infinite loop in fib6_info_uses_dev()").
Writers holding tb6_lock can list_del_rcu(&first->fib6_siblings)
without waiting for RCU readers; first->fib6_siblings.next then
still points into the old ring and this softirq-side walker never
reaches &first->fib6_siblings as its terminator. fib6_purge_rt()
always WRITE_ONCE()s first->fib6_nsiblings to 0 before
list_del_rcu(), so an inside-loop check is a reliable detach signal.
[1] https://sashiko.dev/#/patchset/20260526020227.4857-1-jiayuan.chen%40linux.dev |
| pypdf is a free and open-source pure-python PDF library. Prior to 6.21.4, pypdf can enter an infinite loop while opening a crafted incomplete PDF whose standard cross-reference table reaches the end of the file without a trailer. The trailer search can repeatedly rewind to the same stream position instead of terminating when parsing makes no progress, blocking the processing thread. This issue is fixed in version 6.21.4. |
| pypdf is a free and open-source pure-python PDF library. Prior to 6.21.4, pypdf can enter an infinite loop when cloning or duplicating a crafted cyclic DictionaryObject. Clone traversal checked generated destination references rather than the original source references, allowing some source cycles to evade the visited-object check. This issue is fixed in version 6.21.4. |
| Forge (also called node-forge) is a native implementation of Transport Layer Security in JavaScript. Prior to 1.4.1, the affected implementation used BigInteger.prototype.modInverse(), bnModInverse(), lib/jsbn.js, RSA public exponent e to process the relevant input or security decision. node-forge's bundled jsbn implementation entered an infinite loop when BigInteger.prototype.modInverse() received a negative value or modulus. An attacker who could control the RSA public exponent passed to key generation, or a direct modInverse() operand, could block the Node.js event loop at full CPU. Parsed DER, PEM, JWK, PKCS#12, X.509, and TLS values are unsigned and cannot trigger this issue. This issue is fixed in version 1.4.1. |
| Pillow is a Python imaging library. Prior to 13.0.0, the TarIO initializer in src/PIL/TarIO.py accepts a negative octal member size and computes a backward seek that returns to the same 512-byte header. When the requested member name does not match, the parser repeatedly reads that header, consumes a full CPU core, and never returns. TarIO is reached only when an application directly uses PIL.TarIO.TarIO rather than the default Image.open() path. This issue is fixed in version 13.0.0. |
| In the Linux kernel, the following vulnerability has been resolved:
Input: atmel_mxt_ts - fix boundary check in mxt_prepare_cfg_mem
When a configuration file provides an object size that is larger than the
driver's known mxt_obj_size(object), the driver intends to discard the
extra bytes.
The loop iterates using for (i = 0; i < size; i++). Inside the loop, the
condition to skip processing extra bytes is:
if (i > mxt_obj_size(object))
continue;
Since i is a 0-based index, the valid indices for the object are 0 through
mxt_obj_size(object) - 1.
When i == mxt_obj_size(object), the condition evaluates to false, and the
code processes the byte instead of discarding it.
This causes the code to calculate byte_offset = reg + i - cfg->start_ofs
and writes the byte there, overwriting exactly one byte of the adjacent
instance or object.
Update the boundary check to skip extra bytes correctly by using >=. |
| In the Linux kernel, the following vulnerability has been resolved:
dm-integrity: fix infinite loop on discard with large tag size
When integrity_metadata handles a discard, it fills a buffer with
DISCARD_FILLER and writes it over the tags, max_blocks blocks at a
time. If the kmalloc fails, the buffer is the on-stack array
checksums_onstack and max_size is set to HASH_MAX_DIGESTSIZE. So if the
tag size is larger than HASH_MAX_DIGESTSIZE, max_blocks is zero, bi_size
is never decremented and the loop never terminates.
Fix this by using sizeof(checksums_onstack) as max_size. The array has
MAX_TAG_SIZE bytes since commit b93b6643e9b5 ("dm integrity: fix a
crash with unusually large tag size"), so max_blocks is at least 1. |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring/cancel: don't spin on local work the task can't run
io_uring_cancel_generic() refuses to sleep while any ring on the exiting
task's tctx has local work pending. It assumes the task is that ring's
submitter and that the next io_uring_try_cancel_requests() pass will run
the work. This does not hold for a ring that was still
IORING_SETUP_R_DISABLED when the task got its tctx node from
io_uring_create() or io_ringfd_register(). The submitter is set later by
IORING_REGISTER_ENABLE_RINGS, possibly from another task, and only the
submitter may run local work on an IORING_SETUP_DEFER_TASKRUN ring. To
the exiting task the work stays pending forever, the loop never reaches
schedule(), and the task trips the WARN_ON_ONCE() once and then spins in
do_exit().
An unprivileged user can set this up at will by creating a disabled
ring, having a child enable it and stop, posting to the ring with
IORING_OP_MSG_RING and exiting with a request in flight that only the
child can complete. The exiting thread burns a CPU until the child runs
or dies, and with panic_on_warn set the WARN panics the kernel.
Fix by skipping the sleep only when io_allowed_defer_tw_run() allows the
task to run the work. This is reasonable since work it cannot run cannot
complete any of its requests either, so nothing is lost by sleeping.
Drop the WARN_ON_ONCE() since handing a disabled ring to another thread
is a supported scenario, not a bug state. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: validate chunk length in the inqueue parser
SCTP chunks always include a four-byte generic header, but
sctp_inq_pop() currently accepts shorter declared lengths. A zero-length
chunk leaves chunk_end at the current header.
When ASCONF is covered by the association's SCTP-AUTH policy,
sctp_assoc_bh_rcv() can continue before the state machine performs its
normal chunk-length check. sctp_inq_pop() then returns the same malformed
chunk repeatedly and the receive softirq can lock up.
A remote SCTP peer can trigger this after establishing an association on
a kernel built with CONFIG_IP_SCTP and configured with
net.sctp.addip_enable=1 and net.sctp.auth_enable=1. The reproducer did
not require application credentials, a shared SCTP AUTH key, or
net.sctp.addip_noauth_enable=1.
On commit f967455fb2a5 ("seg6: reset IP6CB after IPv6 decapsulation"),
one zero-length ASCONF caused repeated
watchdog soft-lockup reports in a two-vCPU KVM guest. All 3 pre-trigger
health probes succeeded, while 36 of 37 post-trigger probes failed. With
this change, all 37 post-trigger probes succeeded and no equivalent
soft-lockup signature appeared.
Reject chunks shorter than the generic SCTP header at the shared inqueue
parser boundary. Mark the packet for discard before either caller can
continue processing it, while preserving the four-byte generic minimum.
Declared-length 1 through 4 controls and kernel-generated ASCONF traffic
remained healthy. The patched sctp_hello selftest passed for IPv4 and
IPv6.
The complete private reproducer and validation evidence are available
directly to maintainers on request. |
| In the Linux kernel, the following vulnerability has been resolved:
openvswitch: fix soft lockup in the netlink flow dump
A production compute node carrying a few thousand datapath flows hit a
soft lockup inside a single netlink flow dump and panicked.
ovs_flow_cmd_dump() calls ovs_flow_stats_get() for every flow it
emits, and that releases stats->lock with spin_unlock_bh() once per
CPU that has touched the flow. Every release is a local_bh_enable(),
and each one runs the pending softirq backlog in the dumping thread's
own context.
The skb bounds the flows one callback emits, but not the softirq work
it absorbs. On a CPU that carries the box's packet load the backlog
refills as fast as it drains, so the dumping thread becomes that CPU's
softirq engine. It never sleeps and it has no reschedule point, so
under voluntary preemption nothing can take the CPU away from it:
neither the ksoftirqd the kernel woke to take the work over, nor the
stopper thread the softlockup detector dispatches to refresh its
timestamp.
Hold BH off across the whole callback instead, the way
ctnetlink_dump_table() does, so the nested spin_unlock_bh() stop
draining softirqs. The loop already runs under rcu_read_lock() and
cannot sleep. What it gives up is preemption under CONFIG_PREEMPT,
since a BH-off region is not preemptible outside PREEMPT_RT. The
region stays short: the skb caps the flows one callback emits, and
empty buckets cost no skb space but are each visited once per dump, as
the cursor only moves forward. The table grows on insert and shrinks
only on flush, so the walk is bounded by the largest flow count the
datapath has held. The softirq backlog the callback used to absorb has
no bound at all. |
| In the Linux kernel, the following vulnerability has been resolved:
namespace: don't inherit MNT_UMOUNT in clone_mnt()
MNT_UMOUNT gets raised on a mount that umount_tree() or umount_one() has
taken out of its namespace. It's never cleared. __detach_mounts()
unhooks a mount that carries it instead of unmounting it.
disconnect_mount() lets an unmounted child stay attached only if its
parent carries it. propagate_umount() takes it as the sign that a mount
is going to be unmounted when it decides what else can be unmounted,
where a chain of locked mounts ends and where a for reparenting an
overmount.
clone_mnt() copies the flags of the source and only masks
MNT_INTERNAL_FLAGS which doesn't include MNT_UMOUNT. A mount that was
lazily unmounted but is kept alive by a file descriptor can still be
copied when its root is an nsfs or pidfs file because may_copy_tree()
accepts those before checking whether the source is mounted at all:
mount --bind /proc/self/ns/net /tmp/x
exec 3< /tmp/x
umount -l /tmp/x
mount --bind /proc/self/fd/3 /tmp/y
The mount on /tmp/y is attached to the caller's namespace with
MNT_UMOUNT already set and every copy of it inherits the flag again.
That causes a number of bugs:
- Unlink its mountpoint from a mount namespace where it isn't one.
__detach_mounts() takes it for a mount that was unmounted earlier,
unhooks it from its parent and drops the reference the namespace
holds on it. It stays in the namespace with one reference too few
and as its own parent, so it can't be unmounted through the file
descriptor anymore and the namespace never finds it again. When the
namespace goes away it's leaked and points to a freed struct
mnt_namespace that may_change_propagation() and anon_ns_root() read
on the next propagation change or mount_setattr() through the file
descriptor.
- Make it shared and unmount a peer. trace_transfers() follows the
flag from the peer into it and strips it from its peer group.
- Let a propagated umount reach it. gather_candidates() marks it with
T_UMOUNT_CANDIDATE but never puts it on the candidate list, so the
mark is never cleared and every later propagated umount skips it. If
it's the parent of a locked mount handle_locked() takes it as the
cutoff and commits the locked child that should have stayed and
disconnect_mount() leaves that child attached to it, unmounted under
a mounted parent, which is what disconnect_mount() exists to
prevent. When the namespace goes away umount_tree() visits the child
a second time. And once __detach_mounts() has made it its own parent
reparent() never finds the end of the chain of unmounted parents.
A clone is a new mount that has never been unmounted. Add MNT_UMOUNT
to MNT_INTERNAL_FLAGS so clone_mnt() never copies it. And warn when
umount_tree() reaches a mount that already has it set. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix soft lockup polling continuation IOCB signature
qla27xx_copy_multiple_pkt() and qla27xx_copy_fpin_pkt() poll
rsp_q->ring_ptr->signature for RESPONSE_PROCESSED (0xDEADDEAD) to decide
whether the next continuation IOCB has arrived, spinning on cpu_relax()
without advancing the ring or decrementing the entry count while it has
not. response_t::signature lives at byte offset 60, but a continuation
IOCB (sts_cont_entry_t / struct sts_cont_entry_ext) carries raw FC frame
payload at that offset (data[56..59]). A received frame whose payload
bytes happen to equal 0xDEADDEAD is therefore misread as "not yet
arrived", and the loop spins forever in interrupt/DPC context, causing a
CPU soft lockup.
The poll is also unnecessary: callers of qla27xx_copy_multiple_pkt()
(PT_LS4_UNSOL and the NVMe purls path) already gate on
qla_chk_cont_iocb_avail(), which guarantees all entry_count IOCBs are
present before copying begins. The sibling helper
__qla_copy_purex_to_buffer() already drops the signature poll and relies
on the entry_type == STATUS_CONT_TYPE guard instead.
Remove the signature busy-wait from both helpers, keeping the entry_type
guard, and gate the FPIN path with qla_chk_cont_iocb_avail() so it defers
and re-processes on the next interrupt once all continuation IOCBs have
arrived, mirroring the ELS_AUTH_ELS and PT_LS4_UNSOL arms. With this the
signature field is never read on a continuation IOCB, eliminating the
payload-aliasing lockup. |
| In the Linux kernel, the following vulnerability has been resolved:
exfat: fix handling of damaged volume in exfat_create_upcase_table()
When the size of the upcase table is set to zero in the dentry for any
reason(e.g. corrupted media or misbehaving device), an integer overflow
causes the module to loop indefinitely.
If the size of the upcase table is read zero, do not attempt to load the
table. Instead, fallback to loading the default upcase table. If the
size of the upcase table is zero or no upcase table is found, raise
exfat_fs_error() to mark the volume read-only. |
| In the Linux kernel, the following vulnerability has been resolved:
device property: fix infinite loop in fwnode_for_each_child_node()
When iterate over children of a fwnode that has a secondary fwnode,
fwnode_get_next_child_node() can enter an infinite loop if the secondary
fwnode has more than one child.
Parent Child
(Primary fwnode) FWa: {FWa1, FWa2, FWa3}
(Secondary fwnode) FWb: {FWb1, FWb2}
In this case:
┌─> fwnode_get_next_child_node(FWa, FWa1)
│ - fwnode_call_ptr_op(FWa, get_next_child_node, FWa1) returns FWa2
│
│ ...
│
│ fwnode_get_next_child_node(FWa, FWa3)
│ - fwnode_call_ptr_op(FWa, get_next_child_node, FWa3) returns NULL
│ - fwnode_call_ptr_op(FWb, get_next_child_node, FWa3) returns FWb1
│
│ fwnode_get_next_child_node(FWa, FWb1)
│ - fwnode_call_ptr_op(FWa, get_next_child_node, FWb1) returns FWa1
└────┘
This cause fwnode_for_each_child_node() to loop indefinitely, reapeatedly
output {FWa1, FWa2, FWa3, FWb1, FWa1, ...}.
The root cause is that when the current child (FWb1) belongs to the
secondary fwnode, calling get_next_child_node() on the parimary fwnode
incorrectly returns the first child (FWa1) again instead of NULL.
Fix this by dynamically checking the parent fwnode of the current child
before calling get_next_child_node(). This approach follows the pattern
established in commit b5b41ab6b0c1 ("device property: Check
fwnode->secondary in fwnode_graph_get_next_endpoint()"). |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: do not repeat ceph_trim_dentries() if no progress possible
ceph_cap_reclaim_work() re-queues itself for as long as
ceph_trim_dentries() returns -EAGAIN, which happens whenever a lease
walk exhausts its `nr_to_scan` budget. This creates a busy loop that
consumes CPU without making any progress when there is nothing to
reclaim: with no cap pressure (`count==0`) and every scanned lease
still valid, each pass runs the full scan budget down to zero and
returns `-EAGAIN`, only to be queued again immediately.
The dir-lease walk made this worse. When `expire_dir_lease` is
`false` (i.e. we have no intention of reclaiming dir leases),
__dir_lease_check() returned `TOUCH` for every valid lease. `TOUCH`
moves the dentry to the tail of the list and resets `di->time` via
__dentry_dir_lease_touch(), so a walk over N valid leases pointlessly
rewrote the list, refreshed the timestamps (preventing them from ever
aging out) and always drained `nr_to_scan`, guaranteeing the `-EAGAIN`
requeue.
Fix this in three steps:
- Return `KEEP` instead of `TOUCH` when `expire_dir_lease` is
`false`. If we are not going to reclaim the lease, leave it in
place instead of churning the list and resetting its timestamp; the
walk then terminates naturally (or via `STOP` at the first fresh
lease).
- Only return `-EAGAIN` from the first (dentry-lease) walk when something
was actually freed. A full batch that frees nothing means retrying
the same list immediately is futile; fall through to the dir-lease
walk instead.
- After both walks, bail out with success (0) when nothing was freed
and there is no cap pressure (`count==0`). There is no reason to
keep retrying when we are not over the cap limit and made no
progress.
Under real cap pressure (`count>0`) the reclaim path is unchanged and
still retries via `-EAGAIN`.
Without this patch, I saw 500 ceph_trim_dentries() calls per second on
our web servers. This is very visible in `/proc/lock_stat` (5 minute
capture):
class name con-bounces contentions waittime-min waittime-max waittime-total waittime-avg acq-bounces acquisitions holdtime-min holdtime-max holdtime-total holdtime-avg
&mdsc->dentry_list_lock: 126180 128218 0.04 8063.44 15986965.20 124.69 1573354 5296812 0.04 8291.28 74164526.48 14.00
-----------------------
&mdsc->dentry_list_lock 111736 [<000000007b11e319>] __ceph_dentry_dir_lease_touch+0x7c/0xa8
&mdsc->dentry_list_lock 2631 [<0000000050597999>] __dentry_leases_walk+0x64/0x2c8
&mdsc->dentry_list_lock 3878 [<00000000c0022f62>] __ceph_dentry_lease_touch+0x5c/0xa8
&mdsc->dentry_list_lock 9973 [<000000002f27cb6f>] __dentry_lease_unlist+0x50/0xa0
-----------------------
&mdsc->dentry_list_lock 123621 [<0000000050597999>] __dentry_leases_walk+0x64/0x2c8
&mdsc->dentry_list_lock 1822 [<000000007b11e319>] __ceph_dentry_dir_lease_touch+0x7c/0xa8
&mdsc->dentry_list_lock 2720 [<000000002f27cb6f>] __dentry_lease_unlist+0x50/0xa0
&mdsc->dentry_list_lock 55 [<00000000c0022f62>] __ceph_dentry_lease_touch+0x5c/0xa8
With this patch:
class name con-bounces contentions waittime-min waittime-max waittime-total waittime-avg acq-bounces acquisitions holdtime-min holdtime-max holdtime-total holdtime-avg
&mdsc->dentry_list_lock: 1203 1215 0.16 408.88 33082.88 27.23 4320501 7357389 0.04 500.64 1961578.00 0.27
-----------------------
&mdsc->dentry_list_lock 1029 [<000000003c9aea8a>] __ceph_dentry_dir_lease_touch+0x7c/0xa8
&mdsc->dentry_list_lock 1
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ata: sata_dwc_460ex: fix infinite loop in NCQ tag completion bit-scanning
The hand-rolled bit-scanning loop in the NCQ completion path has an
infinite loop bug. When tag_mask has only high bits set (e.g.
0x80000000), the inner while loop left-shifts tag_mask until it
overflows to 0. At that point !(0 & 1) is always true and 0 <<= 1
stays 0, causing an infinite loop in hardirq context with a spinlock
held.
Replace the open-coded bit-scanning with __ffs() which correctly
finds the least significant set bit and is bounded by the width of
the argument. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/i915/mst: limit DP MST ESI service loop
The loop in intel_dp_check_mst_status() keeps servicing interrupts
originating from the sink without bound. Add an upper bound to the new
interrupts occurring during interrupt processing to not get stuck on
potentially stuck sink devices. Use arbitrary 32 tries to clear incoming
interrupts in one go.
Discovered using AI-assisted static analysis confirmed by Intel Product
Security.
Note: The condition likely pre-dates the commit in the Fixes: tag, but
this is about as far back as a backport has any chance of
succeeding. Before that, the retry had a goto.
(cherry picked from commit b4ea5272133059acb493cc36599071a9e852ec2e) |
| In the Linux kernel, the following vulnerability has been resolved:
rcu: Fix rcu_read_unlock() deadloop due to softirq
Commit 5f5fa7ea89dc ("rcu: Don't use negative nesting depth in
__rcu_read_unlock()") removes the recursion-protection code from
__rcu_read_unlock(). Therefore, we could invoke the deadloop in
raise_softirq_irqoff() with ftrace enabled as follows:
WARNING: CPU: 0 PID: 0 at kernel/trace/trace.c:3021 __ftrace_trace_stack.constprop.0+0x172/0x180
Modules linked in: my_irq_work(O)
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G O 6.18.0-rc7-dirty #23 PREEMPT(full)
Tainted: [O]=OOT_MODULE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:__ftrace_trace_stack.constprop.0+0x172/0x180
RSP: 0018:ffffc900000034a8 EFLAGS: 00010002
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000000000
RDX: 0000000000000003 RSI: ffffffff826d7b87 RDI: ffffffff826e9329
RBP: 0000000000090009 R08: 0000000000000005 R09: ffffffff82afbc4c
R10: 0000000000000008 R11: 0000000000011d7a R12: 0000000000000000
R13: ffff888003874100 R14: 0000000000000003 R15: ffff8880038c1054
FS: 0000000000000000(0000) GS:ffff8880fa8ea000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b31fa7f540 CR3: 00000000078f4005 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
<IRQ>
trace_buffer_unlock_commit_regs+0x6d/0x220
trace_event_buffer_commit+0x5c/0x260
trace_event_raw_event_softirq+0x47/0x80
raise_softirq_irqoff+0x6e/0xa0
rcu_read_unlock_special+0xb1/0x160
unwind_next_frame+0x203/0x9b0
__unwind_start+0x15d/0x1c0
arch_stack_walk+0x62/0xf0
stack_trace_save+0x48/0x70
__ftrace_trace_stack.constprop.0+0x144/0x180
trace_buffer_unlock_commit_regs+0x6d/0x220
trace_event_buffer_commit+0x5c/0x260
trace_event_raw_event_softirq+0x47/0x80
raise_softirq_irqoff+0x6e/0xa0
rcu_read_unlock_special+0xb1/0x160
unwind_next_frame+0x203/0x9b0
__unwind_start+0x15d/0x1c0
arch_stack_walk+0x62/0xf0
stack_trace_save+0x48/0x70
__ftrace_trace_stack.constprop.0+0x144/0x180
trace_buffer_unlock_commit_regs+0x6d/0x220
trace_event_buffer_commit+0x5c/0x260
trace_event_raw_event_softirq+0x47/0x80
raise_softirq_irqoff+0x6e/0xa0
rcu_read_unlock_special+0xb1/0x160
unwind_next_frame+0x203/0x9b0
__unwind_start+0x15d/0x1c0
arch_stack_walk+0x62/0xf0
stack_trace_save+0x48/0x70
__ftrace_trace_stack.constprop.0+0x144/0x180
trace_buffer_unlock_commit_regs+0x6d/0x220
trace_event_buffer_commit+0x5c/0x260
trace_event_raw_event_softirq+0x47/0x80
raise_softirq_irqoff+0x6e/0xa0
rcu_read_unlock_special+0xb1/0x160
__is_insn_slot_addr+0x54/0x70
kernel_text_address+0x48/0xc0
__kernel_text_address+0xd/0x40
unwind_get_return_address+0x1e/0x40
arch_stack_walk+0x9c/0xf0
stack_trace_save+0x48/0x70
__ftrace_trace_stack.constprop.0+0x144/0x180
trace_buffer_unlock_commit_regs+0x6d/0x220
trace_event_buffer_commit+0x5c/0x260
trace_event_raw_event_softirq+0x47/0x80
__raise_softirq_irqoff+0x61/0x80
__flush_smp_call_function_queue+0x115/0x420
__sysvec_call_function_single+0x17/0xb0
sysvec_call_function_single+0x8c/0xc0
</IRQ>
Commit b41642c87716 ("rcu: Fix rcu_read_unlock() deadloop due to IRQ work")
fixed the infinite loop in rcu_read_unlock_special() for IRQ work by
setting a flag before calling irq_work_queue_on(). We fix this issue by
setting the same flag before calling raise_softirq_irqoff() and rename the
flag to defer_qs_pending for more common. |
| In the Linux kernel, the following vulnerability has been resolved:
serial: core: fix infinite loop in handle_tx() for PORT_UNKNOWN
uart_write_room() and uart_write() behave inconsistently when
xmit_buf is NULL (which happens for PORT_UNKNOWN ports that were
never properly initialized):
- uart_write_room() returns kfifo_avail() which can be > 0
- uart_write() checks xmit_buf and returns 0 if NULL
This inconsistency causes an infinite loop in drivers that rely on
tty_write_room() to determine if they can write:
while (tty_write_room(tty) > 0) {
written = tty->ops->write(...);
// written is always 0, loop never exits
}
For example, caif_serial's handle_tx() enters an infinite loop when
used with PORT_UNKNOWN serial ports, causing system hangs.
Fix by making uart_write_room() also check xmit_buf and return 0 if
it's NULL, consistent with uart_write().
Reproducer: https://gist.github.com/mrpre/d9a694cc0e19828ee3bc3b37983fde13 |
