Linux: >> Linux Kernel >> 6.1.93 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
acpi: nfit: fix narrowing conversion in acpi_nfit_ctl
Syzkaller has reported a warning in to_nfit_bus_uuid(): "only secondary
bus families can be translated". This warning is emited if the argument
is equal to NVDIMM_BUS_FAMILY_NFIT == 0. Function acpi_nfit_ctl() first
verifies that a user-provided value call_pkg->nd_family of type u64 is
not equal to 0. Then the value is converted to int, and only after that
is compared to NVDIMM_BUS_FAMILY_MAX. This can lead to passing an invalid
argument to acpi_nfit_ctl(), if call_pkg->nd_family is non-zero, while
the lower 32 bits are zero.
Furthermore, it is best to return EINVAL immediately upon seeing the
invalid user input. The WARNING is insufficient to prevent further
undefined behavior based on other invalid user input.
All checks of the input value should be applied to the original variable
call_pkg->nd_family.
[iweiny: update commit message]
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
x86/mm: Fix flush_tlb_range() when used for zapping normal PMDs
On the following path, flush_tlb_range() can be used for zapping normal
PMD entries (PMD entries that point to page tables) together with the PTE
entries in the pointed-to page table:
collapse_pte_mapped_thp
pmdp_collapse_flush
flush_tlb_range
The arm64 version of flush_tlb_range() has a comment describing that it can
be used for page table removal, and does not use any last-level
invalidation optimizations. Fix the X86 version by making it behave the
same way.
Currently, X86 only uses this information for the following two purposes,
which I think means the issue doesn't have much impact:
- In native_flush_tlb_multi() for checking if lazy TLB CPUs need to be
IPI'd to avoid issues with speculative page table walks.
- In Hyper-V TLB paravirtualization, again for lazy TLB stuff.
The patch "x86/mm: only invalidate final translations with INVLPGB" which
is currently under review (see
<https://lore.kernel.org/all/20241230175550.4046587-13-riel@surriel.com/>)
would probably be making the impact of this a lot worse.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix use-after-free in print_graph_function_flags during tracer switching
Kairui reported a UAF issue in print_graph_function_flags() during
ftrace stress testing [1]. This issue can be reproduced if puting a
'mdelay(10)' after 'mutex_unlock(&trace_types_lock)' in s_start(),
and executing the following script:
$ echo function_graph > current_tracer
$ cat trace > /dev/null &
$ sleep 5 # Ensure the 'cat' reaches the 'mdelay(10)' point
$ echo timerlat > current_tracer
The root cause lies in the two calls to print_graph_function_flags
within print_trace_line during each s_show():
* One through 'iter->trace->print_line()';
* Another through 'event->funcs->trace()', which is hidden in
print_trace_fmt() before print_trace_line returns.
Tracer switching only updates the former, while the latter continues
to use the print_line function of the old tracer, which in the script
above is print_graph_function_flags.
Moreover, when switching from the 'function_graph' tracer to the
'timerlat' tracer, s_start only calls graph_trace_close of the
'function_graph' tracer to free 'iter->private', but does not set
it to NULL. This provides an opportunity for 'event->funcs->trace()'
to use an invalid 'iter->private'.
To fix this issue, set 'iter->private' to NULL immediately after
freeing it in graph_trace_close(), ensuring that an invalid pointer
is not passed to other tracers. Additionally, clean up the unnecessary
'iter->private = NULL' during each 'cat trace' when using wakeup and
irqsoff tracers.
[1] https://lore.kernel.org/all/20231112150030.84609-1-ryncsn@gmail.com/
CVSS Score
7.8
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix null pointer dereference in alloc_preauth_hash()
The Client send malformed smb2 negotiate request. ksmbd return error
response. Subsequently, the client can send smb2 session setup even
thought conn->preauth_info is not allocated.
This patch add KSMBD_SESS_NEED_SETUP status of connection to ignore
session setup request if smb2 negotiate phase is not complete.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: validate zero num_subauth before sub_auth is accessed
Access psid->sub_auth[psid->num_subauth - 1] without checking
if num_subauth is non-zero leads to an out-of-bounds read.
This patch adds a validation step to ensure num_subauth != 0
before sub_auth is accessed.
CVSS Score
7.1
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix overflow in dacloffset bounds check
The dacloffset field was originally typed as int and used in an
unchecked addition, which could overflow and bypass the existing
bounds check in both smb_check_perm_dacl() and smb_inherit_dacl().
This could result in out-of-bounds memory access and a kernel crash
when dereferencing the DACL pointer.
This patch converts dacloffset to unsigned int and uses
check_add_overflow() to validate access to the DACL.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix session use-after-free in multichannel connection
There is a race condition between session setup and
ksmbd_sessions_deregister. The session can be freed before the connection
is added to channel list of session.
This patch check reference count of session before freeing it.
CVSS Score
8.8
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free in ksmbd_sessions_deregister()
In multichannel mode, UAF issue can occur in session_deregister
when the second channel sets up a session through the connection of
the first channel. session that is freed through the global session
table can be accessed again through ->sessions of connection.
CVSS Score
8.8
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
nfsd: put dl_stid if fail to queue dl_recall
Before calling nfsd4_run_cb to queue dl_recall to the callback_wq, we
increment the reference count of dl_stid.
We expect that after the corresponding work_struct is processed, the
reference count of dl_stid will be decremented through the callback
function nfsd4_cb_recall_release.
However, if the call to nfsd4_run_cb fails, the incremented reference
count of dl_stid will not be decremented correspondingly, leading to the
following nfs4_stid leak:
unreferenced object 0xffff88812067b578 (size 344):
comm "nfsd", pid 2761, jiffies 4295044002 (age 5541.241s)
hex dump (first 32 bytes):
01 00 00 00 6b 6b 6b 6b b8 02 c0 e2 81 88 ff ff ....kkkk........
00 6b 6b 6b 6b 6b 6b 6b 00 00 00 00 ad 4e ad de .kkkkkkk.....N..
backtrace:
kmem_cache_alloc+0x4b9/0x700
nfsd4_process_open1+0x34/0x300
nfsd4_open+0x2d1/0x9d0
nfsd4_proc_compound+0x7a2/0xe30
nfsd_dispatch+0x241/0x3e0
svc_process_common+0x5d3/0xcc0
svc_process+0x2a3/0x320
nfsd+0x180/0x2e0
kthread+0x199/0x1d0
ret_from_fork+0x30/0x50
ret_from_fork_asm+0x1b/0x30
unreferenced object 0xffff8881499f4d28 (size 368):
comm "nfsd", pid 2761, jiffies 4295044005 (age 5541.239s)
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 30 4d 9f 49 81 88 ff ff ........0M.I....
30 4d 9f 49 81 88 ff ff 20 00 00 00 01 00 00 00 0M.I.... .......
backtrace:
kmem_cache_alloc+0x4b9/0x700
nfs4_alloc_stid+0x29/0x210
alloc_init_deleg+0x92/0x2e0
nfs4_set_delegation+0x284/0xc00
nfs4_open_delegation+0x216/0x3f0
nfsd4_process_open2+0x2b3/0xee0
nfsd4_open+0x770/0x9d0
nfsd4_proc_compound+0x7a2/0xe30
nfsd_dispatch+0x241/0x3e0
svc_process_common+0x5d3/0xcc0
svc_process+0x2a3/0x320
nfsd+0x180/0x2e0
kthread+0x199/0x1d0
ret_from_fork+0x30/0x50
ret_from_fork_asm+0x1b/0x30
Fix it by checking the result of nfsd4_run_cb and call nfs4_put_stid if
fail to queue dl_recall.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
nfsd: don't ignore the return code of svc_proc_register()
Currently, nfsd_proc_stat_init() ignores the return value of
svc_proc_register(). If the procfile creation fails, then the kernel
will WARN when it tries to remove the entry later.
Fix nfsd_proc_stat_init() to return the same type of pointer as
svc_proc_register(), and fix up nfsd_net_init() to check that and fail
the nfsd_net construction if it occurs.
svc_proc_register() can fail if the dentry can't be allocated, or if an
identical dentry already exists. The second case is pretty unlikely in
the nfsd_net construction codepath, so if this happens, return -ENOMEM.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16