Linux: >> Linux Kernel >> 3.0.94 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix use-after-free bug of ns_writer on remount
If a nilfs2 filesystem is downgraded to read-only due to metadata
corruption on disk and is remounted read/write, or if emergency read-only
remount is performed, detaching a log writer and synchronizing the
filesystem can be done at the same time.
In these cases, use-after-free of the log writer (hereinafter
nilfs->ns_writer) can happen as shown in the scenario below:
Task1 Task2
-------------------------------- ------------------------------
nilfs_construct_segment
nilfs_segctor_sync
init_wait
init_waitqueue_entry
add_wait_queue
schedule
nilfs_remount (R/W remount case)
nilfs_attach_log_writer
nilfs_detach_log_writer
nilfs_segctor_destroy
kfree
finish_wait
_raw_spin_lock_irqsave
__raw_spin_lock_irqsave
do_raw_spin_lock
debug_spin_lock_before <-- use-after-free
While Task1 is sleeping, nilfs->ns_writer is freed by Task2. After Task1
waked up, Task1 accesses nilfs->ns_writer which is already freed. This
scenario diagram is based on the Shigeru Yoshida's post [1].
This patch fixes the issue by not detaching nilfs->ns_writer on remount so
that this UAF race doesn't happen. Along with this change, this patch
also inserts a few necessary read-only checks with superblock instance
where only the ns_writer pointer was used to check if the filesystem is
read-only.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda: fix potential memleak in 'add_widget_node'
As 'kobject_add' may allocated memory for 'kobject->name' when return error.
And in this function, if call 'kobject_add' failed didn't free kobject.
So call 'kobject_put' to recycling resources.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
mISDN: fix possible memory leak in mISDN_dsp_element_register()
Afer commit 1fa5ae857bb1 ("driver core: get rid of struct device's
bus_id string array"), the name of device is allocated dynamically,
use put_device() to give up the reference, so that the name can be
freed in kobject_cleanup() when the refcount is 0.
The 'entry' is going to be freed in mISDN_dsp_dev_release(), so the
kfree() is removed. list_del() is called in mISDN_dsp_dev_release(),
so it need be initialized.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
ata: libata-transport: fix error handling in ata_tdev_add()
In ata_tdev_add(), the return value of transport_add_device() is
not checked. As a result, it causes null-ptr-deref while removing
the module, because transport_remove_device() is called to remove
the device that was not added.
Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0
CPU: 13 PID: 13603 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc3+ #36
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : device_del+0x48/0x3a0
lr : device_del+0x44/0x3a0
Call trace:
device_del+0x48/0x3a0
attribute_container_class_device_del+0x28/0x40
transport_remove_classdev+0x60/0x7c
attribute_container_device_trigger+0x118/0x120
transport_remove_device+0x20/0x30
ata_tdev_delete+0x24/0x50 [libata]
ata_tlink_delete+0x40/0xa0 [libata]
ata_tport_delete+0x2c/0x60 [libata]
ata_port_detach+0x148/0x1b0 [libata]
ata_pci_remove_one+0x50/0x80 [libata]
ahci_remove_one+0x4c/0x8c [ahci]
Fix this by checking and handling return value of transport_add_device()
in ata_tdev_add(). In the error path, device_del() is called to delete
the device which was added earlier in this function, and ata_tdev_free()
is called to free ata_dev.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
ata: libata-transport: fix error handling in ata_tlink_add()
In ata_tlink_add(), the return value of transport_add_device() is
not checked. As a result, it causes null-ptr-deref while removing
the module, because transport_remove_device() is called to remove
the device that was not added.
Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0
CPU: 33 PID: 13850 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc3+ #12
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : device_del+0x48/0x39c
lr : device_del+0x44/0x39c
Call trace:
device_del+0x48/0x39c
attribute_container_class_device_del+0x28/0x40
transport_remove_classdev+0x60/0x7c
attribute_container_device_trigger+0x118/0x120
transport_remove_device+0x20/0x30
ata_tlink_delete+0x88/0xb0 [libata]
ata_tport_delete+0x2c/0x60 [libata]
ata_port_detach+0x148/0x1b0 [libata]
ata_pci_remove_one+0x50/0x80 [libata]
ahci_remove_one+0x4c/0x8c [ahci]
Fix this by checking and handling return value of transport_add_device()
in ata_tlink_add().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
ata: libata-transport: fix error handling in ata_tport_add()
In ata_tport_add(), the return value of transport_add_device() is
not checked. As a result, it causes null-ptr-deref while removing
the module, because transport_remove_device() is called to remove
the device that was not added.
Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0
CPU: 12 PID: 13605 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc3+ #8
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : device_del+0x48/0x39c
lr : device_del+0x44/0x39c
Call trace:
device_del+0x48/0x39c
attribute_container_class_device_del+0x28/0x40
transport_remove_classdev+0x60/0x7c
attribute_container_device_trigger+0x118/0x120
transport_remove_device+0x20/0x30
ata_tport_delete+0x34/0x60 [libata]
ata_port_detach+0x148/0x1b0 [libata]
ata_pci_remove_one+0x50/0x80 [libata]
ahci_remove_one+0x4c/0x8c [ahci]
Fix this by checking and handling return value of transport_add_device()
in ata_tport_add().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
net/x25: Fix skb leak in x25_lapb_receive_frame()
x25_lapb_receive_frame() using skb_copy() to get a private copy of
skb, the new skb should be freed in the undersized/fragmented skb
error handling path. Otherwise there is a memory leak.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
scsi: zfcp: Fix double free of FSF request when qdio send fails
We used to use the wrong type of integer in 'zfcp_fsf_req_send()' to cache
the FSF request ID when sending a new FSF request. This is used in case the
sending fails and we need to remove the request from our internal hash
table again (so we don't keep an invalid reference and use it when we free
the request again).
In 'zfcp_fsf_req_send()' we used to cache the ID as 'int' (signed and 32
bit wide), but the rest of the zfcp code (and the firmware specification)
handles the ID as 'unsigned long'/'u64' (unsigned and 64 bit wide [s390x
ELF ABI]). For one this has the obvious problem that when the ID grows
past 32 bit (this can happen reasonably fast) it is truncated to 32 bit
when storing it in the cache variable and so doesn't match the original ID
anymore. The second less obvious problem is that even when the original ID
has not yet grown past 32 bit, as soon as the 32nd bit is set in the
original ID (0x80000000 = 2'147'483'648) we will have a mismatch when we
cast it back to 'unsigned long'. As the cached variable is of a signed
type, the compiler will choose a sign-extending instruction to load the 32
bit variable into a 64 bit register (e.g.: 'lgf %r11,188(%r15)'). So once
we pass the cached variable into 'zfcp_reqlist_find_rm()' to remove the
request again all the leading zeros will be flipped to ones to extend the
sign and won't match the original ID anymore (this has been observed in
practice).
If we can't successfully remove the request from the hash table again after
'zfcp_qdio_send()' fails (this happens regularly when zfcp cannot notify
the adapter about new work because the adapter is already gone during
e.g. a ChpID toggle) we will end up with a double free. We unconditionally
free the request in the calling function when 'zfcp_fsf_req_send()' fails,
but because the request is still in the hash table we end up with a stale
memory reference, and once the zfcp adapter is either reset during recovery
or shutdown we end up freeing the same memory twice.
The resulting stack traces vary depending on the kernel and have no direct
correlation to the place where the bug occurs. Here are three examples that
have been seen in practice:
list_del corruption. next->prev should be 00000001b9d13800, but was 00000000dead4ead. (next=00000001bd131a00)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:62!
monitor event: 0040 ilc:2 [#1] PREEMPT SMP
Modules linked in: ...
CPU: 9 PID: 1617 Comm: zfcperp0.0.1740 Kdump: loaded
Hardware name: ...
Krnl PSW : 0704d00180000000 00000003cbeea1f8 (__list_del_entry_valid+0x98/0x140)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3
Krnl GPRS: 00000000916d12f1 0000000080000000 000000000000006d 00000003cb665cd6
0000000000000001 0000000000000000 0000000000000000 00000000d28d21e8
00000000d3844000 00000380099efd28 00000001bd131a00 00000001b9d13800
00000000d3290100 0000000000000000 00000003cbeea1f4 00000380099efc70
Krnl Code: 00000003cbeea1e8: c020004f68a7 larl %r2,00000003cc8d7336
00000003cbeea1ee: c0e50027fd65 brasl %r14,00000003cc3e9cb8
#00000003cbeea1f4: af000000 mc 0,0
>00000003cbeea1f8: c02000920440 larl %r2,00000003cd12aa78
00000003cbeea1fe: c0e500289c25 brasl %r14,00000003cc3fda48
00000003cbeea204: b9040043 lgr %r4,%r3
00000003cbeea208: b9040051 lgr %r5,%r1
00000003cbeea20c: b9040032 lgr %r3,%r2
Call Trace:
[<00000003cbeea1f8>] __list_del_entry_valid+0x98/0x140
([<00000003cbeea1f4>] __list_del_entry_valid+0x94/0x140)
[<000003ff7ff502fe>] zfcp_fsf_req_dismiss_all+0xde/0x150 [zfcp]
[<000003ff7ff49cd0>] zfcp_erp_strategy_do_action+0x160/0x280 [zfcp]
---truncated---
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
iio: trigger: sysfs: fix possible memory leak in iio_sysfs_trig_init()
dev_set_name() allocates memory for name, it need be freed
when device_add() fails, call put_device() to give up the
reference that hold in device_initialize(), so that it can
be freed in kobject_cleanup() when the refcount hit to 0.
Fault injection test can trigger this:
unreferenced object 0xffff8e8340a7b4c0 (size 32):
comm "modprobe", pid 243, jiffies 4294678145 (age 48.845s)
hex dump (first 32 bytes):
69 69 6f 5f 73 79 73 66 73 5f 74 72 69 67 67 65 iio_sysfs_trigge
72 00 a7 40 83 8e ff ff 00 86 13 c4 f6 ee ff ff r..@............
backtrace:
[<0000000074999de8>] __kmem_cache_alloc_node+0x1e9/0x360
[<00000000497fd30b>] __kmalloc_node_track_caller+0x44/0x1a0
[<000000003636c520>] kstrdup+0x2d/0x60
[<0000000032f84da2>] kobject_set_name_vargs+0x1e/0x90
[<0000000092efe493>] dev_set_name+0x4e/0x70
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
scsi: target: tcm_loop: Fix possible name leak in tcm_loop_setup_hba_bus()
If device_register() fails in tcm_loop_setup_hba_bus(), the name allocated
by dev_set_name() need be freed. As comment of device_register() says, it
should use put_device() to give up the reference in the error path. So fix
this by calling put_device(), then the name can be freed in kobject_cleanup().
The 'tl_hba' will be freed in tcm_loop_release_adapter(), so it don't need
goto error label in this case.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01