| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/amd: Avoid stack buffer overflow from kernel cmdline
While the kernel command line is considered trusted in most environments,
avoid writing 1 byte past the end of "acpiid" if the "str" argument is
maximum length. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid out-of-boundary access in dnode page
As Jiaming Zhang reported:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x1c1/0x2a0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0x17e/0x800 mm/kasan/report.c:480
kasan_report+0x147/0x180 mm/kasan/report.c:593
data_blkaddr fs/f2fs/f2fs.h:3053 [inline]
f2fs_data_blkaddr fs/f2fs/f2fs.h:3058 [inline]
f2fs_get_dnode_of_data+0x1a09/0x1c40 fs/f2fs/node.c:855
f2fs_reserve_block+0x53/0x310 fs/f2fs/data.c:1195
prepare_write_begin fs/f2fs/data.c:3395 [inline]
f2fs_write_begin+0xf39/0x2190 fs/f2fs/data.c:3594
generic_perform_write+0x2c7/0x910 mm/filemap.c:4112
f2fs_buffered_write_iter fs/f2fs/file.c:4988 [inline]
f2fs_file_write_iter+0x1ec8/0x2410 fs/f2fs/file.c:5216
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x546/0xa90 fs/read_write.c:686
ksys_write+0x149/0x250 fs/read_write.c:738
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x3d0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The root cause is in the corrupted image, there is a dnode has the same
node id w/ its inode, so during f2fs_get_dnode_of_data(), it tries to
access block address in dnode at offset 934, however it parses the dnode
as inode node, so that get_dnode_addr() returns 360, then it tries to
access page address from 360 + 934 * 4 = 4096 w/ 4 bytes.
To fix this issue, let's add sanity check for node id of all direct nodes
during f2fs_get_dnode_of_data(). |
| In the Linux kernel, the following vulnerability has been resolved:
media: venus: Fix OOB read due to missing payload bound check
Currently, The event_seq_changed() handler processes a variable number
of properties sent by the firmware. The number of properties is indicated
by the firmware and used to iterate over the payload. However, the
payload size is not being validated against the actual message length.
This can lead to out-of-bounds memory access if the firmware provides a
property count that exceeds the data available in the payload. Such a
condition can result in kernel crashes or potential information leaks if
memory beyond the buffer is accessed.
Fix this by properly validating the remaining size of the payload before
each property access and updating bounds accordingly as properties are
parsed.
This ensures that property parsing is safely bounded within the received
message buffer and protects against malformed or malicious firmware
behavior. |
| In the Linux kernel, the following vulnerability has been resolved:
benet: fix BUG when creating VFs
benet crashes as soon as SRIOV VFs are created:
kernel BUG at mm/vmalloc.c:3457!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 4 UID: 0 PID: 7408 Comm: test.sh Kdump: loaded Not tainted 6.16.0+ #1 PREEMPT(voluntary)
[...]
RIP: 0010:vunmap+0x5f/0x70
[...]
Call Trace:
<TASK>
__iommu_dma_free+0xe8/0x1c0
be_cmd_set_mac_list+0x3fe/0x640 [be2net]
be_cmd_set_mac+0xaf/0x110 [be2net]
be_vf_eth_addr_config+0x19f/0x330 [be2net]
be_vf_setup+0x4f7/0x990 [be2net]
be_pci_sriov_configure+0x3a1/0x470 [be2net]
sriov_numvfs_store+0x20b/0x380
kernfs_fop_write_iter+0x354/0x530
vfs_write+0x9b9/0xf60
ksys_write+0xf3/0x1d0
do_syscall_64+0x8c/0x3d0
be_cmd_set_mac_list() calls dma_free_coherent() under a spin_lock_bh.
Fix it by freeing only after the lock has been released. |
| In the Linux kernel, the following vulnerability has been resolved:
perf/core: Exit early on perf_mmap() fail
When perf_mmap() fails to allocate a buffer, it still invokes the
event_mapped() callback of the related event. On X86 this might increase
the perf_rdpmc_allowed reference counter. But nothing undoes this as
perf_mmap_close() is never called in this case, which causes another
reference count leak.
Return early on failure to prevent that. |
| In the Linux kernel, the following vulnerability has been resolved:
perf/core: Prevent VMA split of buffer mappings
The perf mmap code is careful about mmap()'ing the user page with the
ringbuffer and additionally the auxiliary buffer, when the event supports
it. Once the first mapping is established, subsequent mapping have to use
the same offset and the same size in both cases. The reference counting for
the ringbuffer and the auxiliary buffer depends on this being correct.
Though perf does not prevent that a related mapping is split via mmap(2),
munmap(2) or mremap(2). A split of a VMA results in perf_mmap_open() calls,
which take reference counts, but then the subsequent perf_mmap_close()
calls are not longer fulfilling the offset and size checks. This leads to
reference count leaks.
As perf already has the requirement for subsequent mappings to match the
initial mapping, the obvious consequence is that VMA splits, caused by
resizing of a mapping or partial unmapping, have to be prevented.
Implement the vm_operations_struct::may_split() callback and return
unconditionally -EINVAL.
That ensures that the mapping offsets and sizes cannot be changed after the
fact. Remapping to a different fixed address with the same size is still
possible as it takes the references for the new mapping and drops those of
the old mapping. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix null pointer dereference error in generate_encryptionkey
If client send two session setups with krb5 authenticate to ksmbd,
null pointer dereference error in generate_encryptionkey could happen.
sess->Preauth_HashValue is set to NULL if session is valid.
So this patch skip generate encryption key if session is valid. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget : fix use-after-free in composite_dev_cleanup()
1. In func configfs_composite_bind() -> composite_os_desc_req_prepare():
if kmalloc fails, the pointer cdev->os_desc_req will be freed but not
set to NULL. Then it will return a failure to the upper-level function.
2. in func configfs_composite_bind() -> composite_dev_cleanup():
it will checks whether cdev->os_desc_req is NULL. If it is not NULL, it
will attempt to use it.This will lead to a use-after-free issue.
BUG: KASAN: use-after-free in composite_dev_cleanup+0xf4/0x2c0
Read of size 8 at addr 0000004827837a00 by task init/1
CPU: 10 PID: 1 Comm: init Tainted: G O 5.10.97-oh #1
kasan_report+0x188/0x1cc
__asan_load8+0xb4/0xbc
composite_dev_cleanup+0xf4/0x2c0
configfs_composite_bind+0x210/0x7ac
udc_bind_to_driver+0xb4/0x1ec
usb_gadget_probe_driver+0xec/0x21c
gadget_dev_desc_UDC_store+0x264/0x27c |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: Restrict conditions for adding duplicating netems to qdisc tree
netem_enqueue's duplication prevention logic breaks when a netem
resides in a qdisc tree with other netems - this can lead to a
soft lockup and OOM loop in netem_dequeue, as seen in [1].
Ensure that a duplicating netem cannot exist in a tree with other
netems.
Previous approaches suggested in discussions in chronological order:
1) Track duplication status or ttl in the sk_buff struct. Considered
too specific a use case to extend such a struct, though this would
be a resilient fix and address other previous and potential future
DOS bugs like the one described in loopy fun [2].
2) Restrict netem_enqueue recursion depth like in act_mirred with a
per cpu variable. However, netem_dequeue can call enqueue on its
child, and the depth restriction could be bypassed if the child is a
netem.
3) Use the same approach as in 2, but add metadata in netem_skb_cb
to handle the netem_dequeue case and track a packet's involvement
in duplication. This is an overly complex approach, and Jamal
notes that the skb cb can be overwritten to circumvent this
safeguard.
4) Prevent the addition of a netem to a qdisc tree if its ancestral
path contains a netem. However, filters and actions can cause a
packet to change paths when re-enqueued to the root from netem
duplication, leading us to the current solution: prevent a
duplicating netem from inhabiting the same tree as other netems.
[1] https://lore.kernel.org/netdev/8DuRWwfqjoRDLDmBMlIfbrsZg9Gx50DHJc1ilxsEBNe2D6NMoigR_eIRIG0LOjMc3r10nUUZtArXx4oZBIdUfZQrwjcQhdinnMis_0G7VEk=@willsroot.io/
[2] https://lwn.net/Articles/719297/ |
| In the Linux kernel, the following vulnerability has been resolved:
LoongArch: BPF: Fix jump offset calculation in tailcall
The extra pass of bpf_int_jit_compile() skips JIT context initialization
which essentially skips offset calculation leaving out_offset = -1, so
the jmp_offset in emit_bpf_tail_call is calculated by
"#define jmp_offset (out_offset - (cur_offset))"
is a negative number, which is wrong. The final generated assembly are
as follow.
54: bgeu $a2, $t1, -8 # 0x0000004c
58: addi.d $a6, $s5, -1
5c: bltz $a6, -16 # 0x0000004c
60: alsl.d $t2, $a2, $a1, 0x3
64: ld.d $t2, $t2, 264
68: beq $t2, $zero, -28 # 0x0000004c
Before apply this patch, the follow test case will reveal soft lock issues.
cd tools/testing/selftests/bpf/
./test_progs --allow=tailcalls/tailcall_bpf2bpf_1
dmesg:
watchdog: BUG: soft lockup - CPU#2 stuck for 26s! [test_progs:25056] |
| In the Linux kernel, the following vulnerability has been resolved:
nfsd: handle get_client_locked() failure in nfsd4_setclientid_confirm()
Lei Lu recently reported that nfsd4_setclientid_confirm() did not check
the return value from get_client_locked(). a SETCLIENTID_CONFIRM could
race with a confirmed client expiring and fail to get a reference. That
could later lead to a UAF.
Fix this by getting a reference early in the case where there is an
extant confirmed client. If that fails then treat it as if there were no
confirmed client found at all.
In the case where the unconfirmed client is expiring, just fail and
return the result from get_client_locked(). |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: asix_devices: add phy_mask for ax88772 mdio bus
Without setting phy_mask for ax88772 mdio bus, current driver may create
at most 32 mdio phy devices with phy address range from 0x00 ~ 0x1f.
DLink DUB-E100 H/W Ver B1 is such a device. However, only one main phy
device will bind to net phy driver. This is creating issue during system
suspend/resume since phy_polling_mode() in phy_state_machine() will
directly deference member of phydev->drv for non-main phy devices. Then
NULL pointer dereference issue will occur. Due to only external phy or
internal phy is necessary, add phy_mask for ax88772 mdio bus to workarnoud
the issue. |
| In the Linux kernel, the following vulnerability has been resolved:
netlink: avoid infinite retry looping in netlink_unicast()
netlink_attachskb() checks for the socket's read memory allocation
constraints. Firstly, it has:
rmem < READ_ONCE(sk->sk_rcvbuf)
to check if the just increased rmem value fits into the socket's receive
buffer. If not, it proceeds and tries to wait for the memory under:
rmem + skb->truesize > READ_ONCE(sk->sk_rcvbuf)
The checks don't cover the case when skb->truesize + sk->sk_rmem_alloc is
equal to sk->sk_rcvbuf. Thus the function neither successfully accepts
these conditions, nor manages to reschedule the task - and is called in
retry loop for indefinite time which is caught as:
rcu: INFO: rcu_sched self-detected stall on CPU
rcu: 0-....: (25999 ticks this GP) idle=ef2/1/0x4000000000000000 softirq=262269/262269 fqs=6212
(t=26000 jiffies g=230833 q=259957)
NMI backtrace for cpu 0
CPU: 0 PID: 22 Comm: kauditd Not tainted 5.10.240 #68
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc42 04/01/2014
Call Trace:
<IRQ>
dump_stack lib/dump_stack.c:120
nmi_cpu_backtrace.cold lib/nmi_backtrace.c:105
nmi_trigger_cpumask_backtrace lib/nmi_backtrace.c:62
rcu_dump_cpu_stacks kernel/rcu/tree_stall.h:335
rcu_sched_clock_irq.cold kernel/rcu/tree.c:2590
update_process_times kernel/time/timer.c:1953
tick_sched_handle kernel/time/tick-sched.c:227
tick_sched_timer kernel/time/tick-sched.c:1399
__hrtimer_run_queues kernel/time/hrtimer.c:1652
hrtimer_interrupt kernel/time/hrtimer.c:1717
__sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1113
asm_call_irq_on_stack arch/x86/entry/entry_64.S:808
</IRQ>
netlink_attachskb net/netlink/af_netlink.c:1234
netlink_unicast net/netlink/af_netlink.c:1349
kauditd_send_queue kernel/audit.c:776
kauditd_thread kernel/audit.c:897
kthread kernel/kthread.c:328
ret_from_fork arch/x86/entry/entry_64.S:304
Restore the original behavior of the check which commit in Fixes
accidentally missed when restructuring the code.
Found by Linux Verification Center (linuxtesting.org). |
| In the Linux kernel, the following vulnerability has been resolved:
smb3: fix for slab out of bounds on mount to ksmbd
With KASAN enabled, it is possible to get a slab out of bounds
during mount to ksmbd due to missing check in parse_server_interfaces()
(see below):
BUG: KASAN: slab-out-of-bounds in
parse_server_interfaces+0x14ee/0x1880 [cifs]
Read of size 4 at addr ffff8881433dba98 by task mount/9827
CPU: 5 UID: 0 PID: 9827 Comm: mount Tainted: G
OE 6.16.0-rc2-kasan #2 PREEMPT(voluntary)
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Dell Inc. Precision Tower 3620/0MWYPT,
BIOS 2.13.1 06/14/2019
Call Trace:
<TASK>
dump_stack_lvl+0x9f/0xf0
print_report+0xd1/0x670
__virt_addr_valid+0x22c/0x430
? parse_server_interfaces+0x14ee/0x1880 [cifs]
? kasan_complete_mode_report_info+0x2a/0x1f0
? parse_server_interfaces+0x14ee/0x1880 [cifs]
kasan_report+0xd6/0x110
parse_server_interfaces+0x14ee/0x1880 [cifs]
__asan_report_load_n_noabort+0x13/0x20
parse_server_interfaces+0x14ee/0x1880 [cifs]
? __pfx_parse_server_interfaces+0x10/0x10 [cifs]
? trace_hardirqs_on+0x51/0x60
SMB3_request_interfaces+0x1ad/0x3f0 [cifs]
? __pfx_SMB3_request_interfaces+0x10/0x10 [cifs]
? SMB2_tcon+0x23c/0x15d0 [cifs]
smb3_qfs_tcon+0x173/0x2b0 [cifs]
? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs]
? cifs_get_tcon+0x105d/0x2120 [cifs]
? do_raw_spin_unlock+0x5d/0x200
? cifs_get_tcon+0x105d/0x2120 [cifs]
? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs]
cifs_mount_get_tcon+0x369/0xb90 [cifs]
? dfs_cache_find+0xe7/0x150 [cifs]
dfs_mount_share+0x985/0x2970 [cifs]
? check_path.constprop.0+0x28/0x50
? save_trace+0x54/0x370
? __pfx_dfs_mount_share+0x10/0x10 [cifs]
? __lock_acquire+0xb82/0x2ba0
? __kasan_check_write+0x18/0x20
cifs_mount+0xbc/0x9e0 [cifs]
? __pfx_cifs_mount+0x10/0x10 [cifs]
? do_raw_spin_unlock+0x5d/0x200
? cifs_setup_cifs_sb+0x29d/0x810 [cifs]
cifs_smb3_do_mount+0x263/0x1990 [cifs] |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: usb-audio: Validate UAC3 power domain descriptors, too
UAC3 power domain descriptors need to be verified with its variable
bLength for avoiding the unexpected OOB accesses by malicious
firmware, too. |
| In the Linux kernel, the following vulnerability has been resolved:
posix-cpu-timers: fix race between handle_posix_cpu_timers() and posix_cpu_timer_del()
If an exiting non-autoreaping task has already passed exit_notify() and
calls handle_posix_cpu_timers() from IRQ, it can be reaped by its parent
or debugger right after unlock_task_sighand().
If a concurrent posix_cpu_timer_del() runs at that moment, it won't be
able to detect timer->it.cpu.firing != 0: cpu_timer_task_rcu() and/or
lock_task_sighand() will fail.
Add the tsk->exit_state check into run_posix_cpu_timers() to fix this.
This fix is not needed if CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y, because
exit_task_work() is called before exit_notify(). But the check still
makes sense, task_work_add(&tsk->posix_cputimers_work.work) will fail
anyway in this case. |
| In the Linux kernel, the following vulnerability has been resolved:
net, hsr: reject HSR frame if skb can't hold tag
Receiving HSR frame with insufficient space to hold HSR tag in the skb
can result in a crash (kernel BUG):
[ 45.390915] skbuff: skb_under_panic: text:ffffffff86f32cac len:26 put:14 head:ffff888042418000 data:ffff888042417ff4 tail:0xe end:0x180 dev:bridge_slave_1
[ 45.392559] ------------[ cut here ]------------
[ 45.392912] kernel BUG at net/core/skbuff.c:211!
[ 45.393276] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI
[ 45.393809] CPU: 1 UID: 0 PID: 2496 Comm: reproducer Not tainted 6.15.0 #12 PREEMPT(undef)
[ 45.394433] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 45.395273] RIP: 0010:skb_panic+0x15b/0x1d0
<snip registers, remove unreliable trace>
[ 45.402911] Call Trace:
[ 45.403105] <IRQ>
[ 45.404470] skb_push+0xcd/0xf0
[ 45.404726] br_dev_queue_push_xmit+0x7c/0x6c0
[ 45.406513] br_forward_finish+0x128/0x260
[ 45.408483] __br_forward+0x42d/0x590
[ 45.409464] maybe_deliver+0x2eb/0x420
[ 45.409763] br_flood+0x174/0x4a0
[ 45.410030] br_handle_frame_finish+0xc7c/0x1bc0
[ 45.411618] br_handle_frame+0xac3/0x1230
[ 45.413674] __netif_receive_skb_core.constprop.0+0x808/0x3df0
[ 45.422966] __netif_receive_skb_one_core+0xb4/0x1f0
[ 45.424478] __netif_receive_skb+0x22/0x170
[ 45.424806] process_backlog+0x242/0x6d0
[ 45.425116] __napi_poll+0xbb/0x630
[ 45.425394] net_rx_action+0x4d1/0xcc0
[ 45.427613] handle_softirqs+0x1a4/0x580
[ 45.427926] do_softirq+0x74/0x90
[ 45.428196] </IRQ>
This issue was found by syzkaller.
The panic happens in br_dev_queue_push_xmit() once it receives a
corrupted skb with ETH header already pushed in linear data. When it
attempts the skb_push() call, there's not enough headroom and
skb_push() panics.
The corrupted skb is put on the queue by HSR layer, which makes a
sequence of unintended transformations when it receives a specific
corrupted HSR frame (with incomplete TAG).
Fix it by dropping and consuming frames that are not long enough to
contain both ethernet and hsr headers.
Alternative fix would be to check for enough headroom before skb_push()
in br_dev_queue_push_xmit().
In the reproducer, this is injected via AF_PACKET, but I don't easily
see why it couldn't be sent over the wire from adjacent network.
Further Details:
In the reproducer, the following network interface chain is set up:
┌────────────────┐ ┌────────────────┐
│ veth0_to_hsr ├───┤ hsr_slave0 ┼───┐
└────────────────┘ └────────────────┘ │
│ ┌──────┐
├─┤ hsr0 ├───┐
│ └──────┘ │
┌────────────────┐ ┌────────────────┐ │ │┌────────┐
│ veth1_to_hsr ┼───┤ hsr_slave1 ├───┘ └┤ │
└────────────────┘ └────────────────┘ ┌┼ bridge │
││ │
│└────────┘
│
┌───────┐ │
│ ... ├──────┘
└───────┘
To trigger the events leading up to crash, reproducer sends a corrupted
HSR fr
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Destroy KFD debugfs after destroy KFD wq
Since KFD proc content was moved to kernel debugfs, we can't destroy KFD
debugfs before kfd_process_destroy_wq. Move kfd_process_destroy_wq prior
to kfd_debugfs_fini to fix a kernel NULL pointer problem. It happens
when /sys/kernel/debug/kfd was already destroyed in kfd_debugfs_fini but
kfd_process_destroy_wq calls kfd_debugfs_remove_process. This line
debugfs_remove_recursive(entry->proc_dentry);
tries to remove /sys/kernel/debug/kfd/proc/<pid> while
/sys/kernel/debug/kfd is already gone. It hangs the kernel by kernel
NULL pointer.
(cherry picked from commit 0333052d90683d88531558dcfdbf2525cc37c233) |
| In the Linux kernel, the following vulnerability has been resolved:
media: venus: protect against spurious interrupts during probe
Make sure the interrupt handler is initialized before the interrupt is
registered.
If the IRQ is registered before hfi_create(), it's possible that an
interrupt fires before the handler setup is complete, leading to a NULL
dereference.
This error condition has been observed during system boot on Rb3Gen2. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/buffer: fix use-after-free when call bh_read() helper
There's issue as follows:
BUG: KASAN: stack-out-of-bounds in end_buffer_read_sync+0xe3/0x110
Read of size 8 at addr ffffc9000168f7f8 by task swapper/3/0
CPU: 3 UID: 0 PID: 0 Comm: swapper/3 Not tainted 6.16.0-862.14.0.6.x86_64
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
<IRQ>
dump_stack_lvl+0x55/0x70
print_address_description.constprop.0+0x2c/0x390
print_report+0xb4/0x270
kasan_report+0xb8/0xf0
end_buffer_read_sync+0xe3/0x110
end_bio_bh_io_sync+0x56/0x80
blk_update_request+0x30a/0x720
scsi_end_request+0x51/0x2b0
scsi_io_completion+0xe3/0x480
? scsi_device_unbusy+0x11e/0x160
blk_complete_reqs+0x7b/0x90
handle_softirqs+0xef/0x370
irq_exit_rcu+0xa5/0xd0
sysvec_apic_timer_interrupt+0x6e/0x90
</IRQ>
Above issue happens when do ntfs3 filesystem mount, issue may happens
as follows:
mount IRQ
ntfs_fill_super
read_cache_page
do_read_cache_folio
filemap_read_folio
mpage_read_folio
do_mpage_readpage
ntfs_get_block_vbo
bh_read
submit_bh
wait_on_buffer(bh);
blk_complete_reqs
scsi_io_completion
scsi_end_request
blk_update_request
end_bio_bh_io_sync
end_buffer_read_sync
__end_buffer_read_notouch
unlock_buffer
wait_on_buffer(bh);--> return will return to caller
put_bh
--> trigger stack-out-of-bounds
In the mpage_read_folio() function, the stack variable 'map_bh' is
passed to ntfs_get_block_vbo(). Once unlock_buffer() unlocks and
wait_on_buffer() returns to continue processing, the stack variable
is likely to be reclaimed. Consequently, during the end_buffer_read_sync()
process, calling put_bh() may result in stack overrun.
If the bh is not allocated on the stack, it belongs to a folio. Freeing
a buffer head which belongs to a folio is done by drop_buffers() which
will fail to free buffers which are still locked. So it is safe to call
put_bh() before __end_buffer_read_notouch(). |