| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
mm/slab: prevent unbounded recursion in free path with new kmalloc type
Commit 280ea9c3154b ("mm/slab: avoid allocating slabobj_ext array from
its own slab") avoided recursive allocation of obj_exts from kmalloc
caches of the same size, by bumping the obj_exts array's allocation
size whenever the array size equals the size of the object being
allocated.
However, as reported by Danielle Costantino and Shakeel Butt,
even slabs from kmalloc caches of different sizes can form a cycle
by allocating obj_exts arrays from each other [1]:
What happened: a KMALLOC_NORMAL slab's obj_exts array (used by
allocation profiling / memcg accounting) is itself kmalloc()'d from a
KMALLOC_NORMAL cache, so the "slab holds another slab's obj_exts array"
relation can form cycles. With sizeof(struct slabobj_ext) == 16 and
the host's geometry:
- kmalloc-512 has 64 objects/slab -> array is 64*16 == 1024 bytes,
served from kmalloc-1k;
- kmalloc-1k has 32 objects/slab -> array is 32*16 == 512 bytes,
served from kmalloc-512.
A kmalloc-512 slab and a kmalloc-1k slab therefore hold each other's
obj_exts array. Discarding one frees the other's array, which empties
and discards that slab, which frees the first's array, and so on:
__free_slab() -> free_slab_obj_exts() -> kfree() -> discard_slab() ->
__free_slab() recurses along the cycle until the stack is exhausted.
With memory allocation profiling, this allows unbounded recursion
in the free path and led to a stack overflow on a production host in
the Meta fleet [1]:
BUG: TASK stack guard page was hit
Oops: stack guard page
RIP: 0010:kfree+0x8/0x5d0
Call Trace:
__free_slab+0x66/0xc0
kfree+0x3f0/0x5d0
... ( ~125x __free_slab <-> kfree ) ...
<kernel driver freeing a resource>
do_syscall_64
It is proposed [1] to resolve this issue by always serving the obj_exts
array allocation from kmalloc caches (or large kmalloc) of sizes larger
than the object size. However, as pointed out by Vlastimil Babka [2],
this can waste an excessive amount of memory as slabs from large
kmalloc sizes (e.g. kmalloc-8k) generally need obj_exts arrays much
smaller than the object size.
Therefore, rather than bumping the size, let us take a different
approach; disallow formation of cycles between kmalloc types when
allocating obj_exts arrays. Currently, all obj_exts arrays are served
from normal kmalloc caches. Cycles cannot be created if obj_exts arrays
of normal kmalloc caches are served from a special kmalloc type that can
never have obj_exts arrays.
To achieve this, create a new kmalloc type called KMALLOC_NO_OBJ_EXT.
KMALLOC_NO_OBJ_EXT caches are created with SLAB_NO_OBJ_EXT flag when
either 1) memory allocation profiling is not permanently disabled,
or 2) kmalloc types with a priority higher than KMALLOC_CGROUP are
aliased with KMALLOC_NORMAL.
Sheaf bootstrapping for KMALLOC_NO_OBJ_EXT caches now must be deferred
because allocation of a barn can trigger obj_exts array allocation of
normal kmalloc caches when the KMALLOC_NO_OBJ_EXT cache for that size
is not ready yet. For simplicity, perform bootstrapping of sheaves for
all kmalloc caches later.
Introduce a new slab alloc flag, SLAB_ALLOC_NO_OBJ_EXT, to prevent
allocation of obj_exts arrays, and let kmalloc_slab() override the type
to KMALLOC_NO_OBJ_EXT when specified. Note that kmalloc_type() remains
unchanged because kmalloc_flags() bypasses the kmalloc fastpath.
Do not pass SLAB_ALLOC_NO_RECURSE to kmalloc_flags() in
alloc_slab_obj_exts() and instead use SLAB_ALLOC_NO_OBJ_EXT only when
the objects are allocated from normal kmalloc caches. While this
prevents unbounded recursive allocation of obj_exts, it allows
KMALLOC_NO_OBJ_EXT caches to have sheaves.
Since sheaf allocations specify SLAB_ALLOC_NO_RECURSE that prevents
allocation of both sheaves and obj_exts arrays, the recursion depth
is bounded.
obj_exts arrays for non-
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix potential infinite loop in rxrpc_recvmsg()
Fix the wait in rxrpc_recvmsg() also take check the oob queue. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Reject sleepable BPF_LSM_CGROUP programs at load time
The cgroup shim runs under rcu_read_lock_dont_migrate(), so we should
not attach any sleepable BPF programs there. Add support to the verifier
to explicitly reject attempts to load sleepable BPF programs destined
for LSM cgroup attachment.
Without this, we get the following splat from a BPF_LSM_CGROUP
program marked BPF_F_SLEEPABLE attached to file_open when it calls
bpf_get_dentry_xattr():
BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1567
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 34317, name: load
preempt_count: 0, expected: 0
RCU nest depth: 2, expected: 0
Call Trace:
down_read+0x76/0x480
ext4_xattr_get+0x11f/0x700
__vfs_getxattr+0xf0/0x150
bpf_get_dentry_xattr+0xbb/0xf0
bpf_prog_e76a298dac9218c6_test_open+0x6a/0x85
__cgroup_bpf_run_lsm_current+0x326/0x840
bpf_trampoline_6442534646+0x62/0x14d
security_file_open+0x34/0x60
do_dentry_open+0x340/0x1260
vfs_open+0x7a/0x440
path_openat+0x1bac/0x30a0
libbpf provides a .s named section variant for every sleepable
program type except lsm_cgroup, reflecting that per-cgroup LSM programs
are intended to only run in a non-sleepable context.
The above splat was obtained by bypassing libbpf by using bpf(2)
directly. |
| Scriban versions 6.6.0 through 7.2.0 contain a non-enforcing ExpressionDepthLimit guard that fails to stop recursive descent parsing of deeply nested expressions. Attackers can supply templates with deeply nested parentheses, array initializers, object initializers, or unary operators to trigger an uncatchable StackOverflowException that immediately terminates the host process. |
| Scriban before 7.0.0 contains an uncontrolled recursion vulnerability in the object.to_json builtin function that lacks depth limits and circular reference detection. Attackers can craft templates with self-referencing objects to trigger unbounded recursion, causing a StackOverflowException that fatally terminates the hosting .NET process. |
| Scriban before 7.0.0 (affected versions <= 6.6.0) contains a stack overflow vulnerability in nested array initializer parsing. Deeply nested array initializers recurse through a path (ParseArrayInitializer → ParseExpression → ParseArrayInitializer) that is not covered by the ExpressionDepthLimit counter added in the fix for GHSA-wgh7-7m3c-fx25. An attacker who can supply untrusted input to Template.Parse can trigger an uncatchable StackOverflowException that immediately terminates the process, even with the default ExpressionDepthLimit enabled. |
| Scriban before 6.6.0 contains an infinite recursion vulnerability in object rendering when the ObjectRecursionLimit property defaults to unlimited. Attackers can supply circular reference objects to the template context, exhausting stack space and triggering an uncatchable StackOverflowException that terminates the hosting process. |
| Scriban before 6.6.0 contains an uncontrolled recursion vulnerability in its recursive-descent parser. The parser does not enforce a default expression depth limit (the ExpressionDepthLimit property in ParserOptions defaults to null/disabled), so an attacker who controls template input can supply a deeply nested template (e.g., thousands of nested parentheses or blocks) that exhausts thread stack space and raises a StackOverflowException. Because a StackOverflowException cannot be caught in .NET, this causes immediate, unrecoverable termination of the hosting process, resulting in a denial of service. Applications that process untrusted or user-supplied templates can be exploited remotely without authentication. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: add depth limit to indx_find_buffer to prevent stack overflow
indx_find_buffer() recursively descends the B+ tree index with no depth
limit. A crafted NTFS image with circular index node references causes
unbounded recursion, overflowing the kernel stack and panicking the
system.
This is reachable by mounting a malicious NTFS filesystem (e.g. from a
USB drive via desktop automount) and deleting a file whose index entry
triggers the rebalancing fallback path in indx_delete_entry().
Add a depth parameter and bail out with -EINVAL when it reaches the
fnd->nodes array bound, matching the constraint already enforced by
fnd_push() in indx_find().
The related function indx_find() was previously patched for a similar
infinite-loop issue (commit 1732053c8a6b), but indx_find_buffer() was
missed. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: pci: Fix memory accounting for pinned/unpinned pages
The account_mem() and unaccount_mem() functions call get_uid() which
increments the reference count of struct user_struct on every invocation.
But we don't decrement the count by calling free_uid(). It also
accounted/unaccounted the pages against the current->mm. But its possible
the unaccount_mem() can be called from a different process context than the
one that originally pinned the pages.
Let's fix this by storing the pinning process user_struct and mm_struct
when accounting for pinned pages, and subsequently free these resources
when the pages are unpinned.
[borntraeger@linux.ibm.com: Fixed whitespace] |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: cls_bpf: prevent unbounded recursion in offload rollback
Quan Sun reported [1] a stack overflow in cls_bpf_offload_cmd().
Reproducer on netdevsim: add a skip_sw cls_bpf filter, set the
bpf_tc_accept debugfs knob to 0, then `tc filter replace`. The replace
calls tc_setup_cb_replace() which fails. cls_bpf_offload_cmd() then
swaps prog/oldprog and recursively calls itself to roll back. But
bpf_tc_accept=0 makes the rollback fail too, which triggers yet another
rollback frame with the same arguments, and so on until the stack is
exhausted.
bpf_tc_accept is just a convenient knob for the reproducer. Any driver
whose tc_setup_cb_replace() fails twice in a row can hit the same loop,
so this is not a netdevsim-only issue.
Two ways to fix it:
1) Have the rollback call tc_setup_cb_add() on oldprog instead of
re-entering cls_bpf_offload_cmd().
2) Mark the rollback frame with a flag and skip a second-level
rollback from inside it.
Go with (2). It is the smaller change and keeps the original behaviour:
the rollback still goes through tc_setup_cb_replace(), so the driver
gets one real chance to restore its state. If that attempt also fails,
we just return the original error instead of recursing.
[1]: https://lore.kernel.org/bpf/ce5a6005-3c5e-4696-9e05-eba9461dc860@std.uestc.edu.cn/T/#u |
| IBM Db2 Mirror for i 7.4, 7.5, and 7.6 could allow a remote attacker to cause a denial of service due to uncontrolled recursion. |
| Courier IMAP before 6.0.1 and Courier Mail Server before 2.0.2 allow authenticated IMAP users to crash the imapd process via deeply nested parenthesized SEARCH queries. The SEARCH command parser (alloc_search_key in searchinfo.C) recursively descends on nested parenthesized groups through a mutual recursion chain with alloc_search_andlist() and alloc_search_notkey(), with no depth limit. Courier IMAP has no overall command line length limit, making exploitation trivial. A single IMAP command with ~2500 nested parentheses overflows the 8MB default stack, causing SIGSEGV. |
| In the Linux kernel, the following vulnerability has been resolved:
accel/ivpu: Fix signed integer truncation in IPC receive
Fix potential buffer overflow where firmware-supplied data_size is cast
to signed int before being used in min_t(). Large unsigned values
(>= 0x80000000) become negative, causing unsigned wraparound and
oversized memcpy operations that can overflow the stack buffer.
Change min_t(int, ...) to min() as both values are unsigned and can be
handled by min() without explicit cast. |
| node-tar is a tar archive manipulation library for Node.js. Prior to 7.5.21, node-tar's filesFilter in src/list.ts uses the recursive mapHas helper to walk an archive entry path upward with path.dirname() and no segment cap when tar.t(...) or tar.x(...) receives a non-empty member-selection list. A crafted GNU L or PAX x long-path header with thousands of slash-separated segments reaches this.filter(entry.path, entry) in Parser[CONSUMEHEADER] in src/parse.ts before Unpack[CHECKPATH] applies maxDepth, causing an uncatchable RangeError stack overflow that terminates asynchronous and streaming Node.js consumers. This issue is fixed in version 7.5.21. |
| A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single request containing a crafted user-supplied input. A specific internal component validates the input using a recursive routine and applies no bound to the length of the value being validated, so the validation causes the thread to exhaust its stack. The resulting fatal error is not handled by the surrounding execution paths and terminates the affected node process, producing a denial of service. |
| Elasticsearch does not apply its configurable input length restriction to a user-supplied pattern accepted by an intervals query. Compiling a deeply nested pattern drives unbounded recursion that exhausts the thread stack and raises a fatal error, terminating the Elasticsearch node process and causing a denial of service for that node. An authenticated user holding only read-only privileges on a single searchable index can trigger the condition with one small search request. |
| A flaw in Elasticsearch allows an authenticated user with the privileges required to invoke the simulate pipeline API endpoint (https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-ingest-simulate) to submit a request that causes a self-referential data structure to be created. When a specific internal component later processes that structure, the operation recurses without bound and raises a fatal error that is not handled by the surrounding execution path, terminating the affected node process and resulting in a denial of service. |
| Uncontrolled Recursion (CWE-674) in Elasticsearch can lead to denial of service via Serialized Data with Nested Payloads (CAPEC-230). An authenticated user holding only read privileges on a single index can submit one specially crafted search request whose deeply nested structure is processed without a depth limit, exhausting the thread stack and terminating the affected node. |
| Uncontrolled Recursion (CWE-674) in Elasticsearch can lead to denial of service via Input Data Manipulation (CAPEC-153). An authenticated user holding only low-privileged index creation permissions can submit a single request containing a specially crafted, malformed custom analysis definition that is resolved recursively without a cycle or depth check, exhausting the thread stack and terminating the affected node. |
