Linux: >> Linux Kernel >> 3.4 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
mm/slub: avoid accessing metadata when pointer is invalid in object_err()
object_err() reports details of an object for further debugging, such as
the freelist pointer, redzone, etc. However, if the pointer is invalid,
attempting to access object metadata can lead to a crash since it does
not point to a valid object.
One known path to the crash is when alloc_consistency_checks()
determines the pointer to the allocated object is invalid because of a
freelist corruption, and calls object_err() to report it. The debug code
should report and handle the corruption gracefully and not crash in the
process.
In case the pointer is NULL or check_valid_pointer() returns false for
the pointer, only print the pointer value and skip accessing metadata.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-01
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix recursive semaphore deadlock in fiemap call
syzbot detected a OCFS2 hang due to a recursive semaphore on a
FS_IOC_FIEMAP of the extent list on a specially crafted mmap file.
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
ocfs2_page_mkwrite+0x2ff/0xc40 fs/ocfs2/mmap.c:142
do_page_mkwrite+0x14d/0x310 mm/memory.c:3361
wp_page_shared mm/memory.c:3762 [inline]
do_wp_page+0x268d/0x5800 mm/memory.c:3981
handle_pte_fault mm/memory.c:6068 [inline]
__handle_mm_fault+0x1033/0x5440 mm/memory.c:6195
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6364
do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
RIP: 0010:raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
RIP: 0010:_inline_copy_to_user include/linux/uaccess.h:197 [inline]
RIP: 0010:_copy_to_user+0x85/0xb0 lib/usercopy.c:26
Code: e8 00 bc f7 fc 4d 39 fc 72 3d 4d 39 ec 77 38 e8 91 b9 f7 fc 4c 89
f7 89 de e8 47 25 5b fd 0f 01 cb 4c 89 ff 48 89 d9 4c 89 f6 <f3> a4 0f
1f 00 48 89 cb 0f 01 ca 48 89 d8 5b 41 5c 41 5d 41 5e 41
RSP: 0018:ffffc9000403f950 EFLAGS: 00050256
RAX: ffffffff84c7f101 RBX: 0000000000000038 RCX: 0000000000000038
RDX: 0000000000000000 RSI: ffffc9000403f9e0 RDI: 0000200000000060
RBP: ffffc9000403fa90 R08: ffffc9000403fa17 R09: 1ffff92000807f42
R10: dffffc0000000000 R11: fffff52000807f43 R12: 0000200000000098
R13: 00007ffffffff000 R14: ffffc9000403f9e0 R15: 0000200000000060
copy_to_user include/linux/uaccess.h:225 [inline]
fiemap_fill_next_extent+0x1c0/0x390 fs/ioctl.c:145
ocfs2_fiemap+0x888/0xc90 fs/ocfs2/extent_map.c:806
ioctl_fiemap fs/ioctl.c:220 [inline]
do_vfs_ioctl+0x1173/0x1430 fs/ioctl.c:532
__do_sys_ioctl fs/ioctl.c:596 [inline]
__se_sys_ioctl+0x82/0x170 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f13850fd9
RSP: 002b:00007ffe3b3518b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000200000000000 RCX: 00007f5f13850fd9
RDX: 0000200000000040 RSI: 00000000c020660b RDI: 0000000000000004
RBP: 6165627472616568 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3b3518f0
R13: 00007ffe3b351b18 R14: 431bde82d7b634db R15: 00007f5f1389a03b
ocfs2_fiemap() takes a read lock of the ip_alloc_sem semaphore (since
v2.6.22-527-g7307de80510a) and calls fiemap_fill_next_extent() to read the
extent list of this running mmap executable. The user supplied buffer to
hold the fiemap information page faults calling ocfs2_page_mkwrite() which
will take a write lock (since v2.6.27-38-g00dc417fa3e7) of the same
semaphore. This recursive semaphore will hold filesystem locks and causes
a hang of the fileystem.
The ip_alloc_sem protects the inode extent list and size. Release the
read semphore before calling fiemap_fill_next_extent() in ocfs2_fiemap()
and ocfs2_fiemap_inline(). This does an unnecessary semaphore lock/unlock
on the last extent but simplifies the error path.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
pcmcia: Fix a NULL pointer dereference in __iodyn_find_io_region()
In __iodyn_find_io_region(), pcmcia_make_resource() is assigned to
res and used in pci_bus_alloc_resource(). There is a dereference of res
in pci_bus_alloc_resource(), which could lead to a NULL pointer
dereference on failure of pcmcia_make_resource().
Fix this bug by adding a check of res.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-19
In the Linux kernel, the following vulnerability has been resolved:
ppp: fix memory leak in pad_compress_skb
If alloc_skb() fails in pad_compress_skb(), it returns NULL without
releasing the old skb. The caller does:
skb = pad_compress_skb(ppp, skb);
if (!skb)
goto drop;
drop:
kfree_skb(skb);
When pad_compress_skb() returns NULL, the reference to the old skb is
lost and kfree_skb(skb) ends up doing nothing, leading to a memory leak.
Align pad_compress_skb() semantics with realloc(): only free the old
skb if allocation and compression succeed. At the call site, use the
new_skb variable so the original skb is not lost when pad_compress_skb()
fails.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-19
In the Linux kernel, the following vulnerability has been resolved:
ax25: properly unshare skbs in ax25_kiss_rcv()
Bernard Pidoux reported a regression apparently caused by commit
c353e8983e0d ("net: introduce per netns packet chains").
skb->dev becomes NULL and we crash in __netif_receive_skb_core().
Before above commit, different kind of bugs or corruptions could happen
without a major crash.
But the root cause is that ax25_kiss_rcv() can queue/mangle input skb
without checking if this skb is shared or not.
Many thanks to Bernard Pidoux for his help, diagnosis and tests.
We had a similar issue years ago fixed with commit 7aaed57c5c28
("phonet: properly unshare skbs in phonet_rcv()").
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-19
In the Linux kernel, the following vulnerability has been resolved:
mfd: arizona: Use pm_runtime_resume_and_get() to prevent refcnt leak
In arizona_clk32k_enable(), we should use pm_runtime_resume_and_get()
as pm_runtime_get_sync() will increase the refcnt even when it
returns an error.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-18
In the Linux kernel, the following vulnerability has been resolved:
scsi: ses: Handle enclosure with just a primary component gracefully
This reverts commit 3fe97ff3d949 ("scsi: ses: Don't attach if enclosure
has no components") and introduces proper handling of case where there are
no detected secondary components, but primary component (enumerated in
num_enclosures) does exist. That fix was originally proposed by Ding Hui
<dinghui@sangfor.com.cn>.
Completely ignoring devices that have one primary enclosure and no
secondary one results in ses_intf_add() bailing completely
scsi 2:0:0:254: enclosure has no enumerated components
scsi 2:0:0:254: Failed to bind enclosure -12ven in valid configurations such
even on valid configurations with 1 primary and 0 secondary enclosures as
below:
# sg_ses /dev/sg0
3PARdata SES 3321
Supported diagnostic pages:
Supported Diagnostic Pages [sdp] [0x0]
Configuration (SES) [cf] [0x1]
Short Enclosure Status (SES) [ses] [0x8]
# sg_ses -p cf /dev/sg0
3PARdata SES 3321
Configuration diagnostic page:
number of secondary subenclosures: 0
generation code: 0x0
enclosure descriptor list
Subenclosure identifier: 0 [primary]
relative ES process id: 0, number of ES processes: 1
number of type descriptor headers: 1
enclosure logical identifier (hex): 20000002ac02068d
enclosure vendor: 3PARdata product: VV rev: 3321
type descriptor header and text list
Element type: Unspecified, subenclosure id: 0
number of possible elements: 1
The changelog for the original fix follows
=====
We can get a crash when disconnecting the iSCSI session,
the call trace like this:
[ffff00002a00fb70] kfree at ffff00000830e224
[ffff00002a00fba0] ses_intf_remove at ffff000001f200e4
[ffff00002a00fbd0] device_del at ffff0000086b6a98
[ffff00002a00fc50] device_unregister at ffff0000086b6d58
[ffff00002a00fc70] __scsi_remove_device at ffff00000870608c
[ffff00002a00fca0] scsi_remove_device at ffff000008706134
[ffff00002a00fcc0] __scsi_remove_target at ffff0000087062e4
[ffff00002a00fd10] scsi_remove_target at ffff0000087064c0
[ffff00002a00fd70] __iscsi_unbind_session at ffff000001c872c4
[ffff00002a00fdb0] process_one_work at ffff00000810f35c
[ffff00002a00fe00] worker_thread at ffff00000810f648
[ffff00002a00fe70] kthread at ffff000008116e98
In ses_intf_add, components count could be 0, and kcalloc 0 size scomp,
but not saved in edev->component[i].scratch
In this situation, edev->component[0].scratch is an invalid pointer,
when kfree it in ses_intf_remove_enclosure, a crash like above would happen
The call trace also could be other random cases when kfree cannot catch
the invalid pointer
We should not use edev->component[] array when the components count is 0
We also need check index when use edev->component[] array in
ses_enclosure_data_process
=====
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-18
In the Linux kernel, the following vulnerability has been resolved:
firewire: net: fix use after free in fwnet_finish_incoming_packet()
The netif_rx() function frees the skb so we can't dereference it to
save the skb->len.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-18
In the Linux kernel, the following vulnerability has been resolved:
cassini: Fix a memory leak in the error handling path of cas_init_one()
cas_saturn_firmware_init() allocates some memory using vmalloc(). This
memory is freed in the .remove() function but not it the error handling
path of the probe.
Add the missing vfree() to avoid a memory leak, should an error occur.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-18
In the Linux kernel, the following vulnerability has been resolved:
media: uvcvideo: Handle cameras with invalid descriptors
If the source entity does not contain any pads, do not create a link.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-18