Nfs-utils: rpc.mountd in the nfs-utils privilege escalation
A vulnerability was recently discovered in the rpc.mountd daemon in the nfs-utils package for Linux, that allows a NFSv3 client to escalate the
privileges assigned to it in the /etc/exports file at mount time. In particular, it allows the client to access any subdirectory or subtree of an exported directory, regardless of the set file permissions, and regardless of any 'root_squash' or 'all_squash' attributes that would normally be expected to apply to that client.
Kernel: secure boot does not automatically enable kernel lockdown
The Linux Kernel lockdown mode for kernel versions starting on 6.12 and above for Fedora Linux has the lockdown mode disabled without any warning. This may allow an attacker to gain access to sensitive information such kernel memory mappings, I/O ports, BPF and kprobes. Additionally unsigned modules can be loaded, leading to execution of untrusted code breaking breaking any Secure Boot protection. This vulnerability affects only Fedora Linux.
In the Linux kernel, the following vulnerability has been resolved:
leds: led-core: Fix refcount leak in of_led_get()
class_find_device_by_of_node() calls class_find_device(), it will take
the reference, use the put_device() to drop the reference when not need
anymore.
f2fs: fix potential corruption when moving a directory
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix potential corruption when moving a directory
F2FS has the same issue in ext4_rename causing crash revealed by
xfstests/generic/707.
See also commit 0813299c586b ("ext4: Fix possible corruption when moving a directory")
can: isotp: check CAN address family in isotp_bind()
In the Linux kernel, the following vulnerability has been resolved:
can: isotp: check CAN address family in isotp_bind()
Add missing check to block non-AF_CAN binds.
Syzbot created some code which matched the right sockaddr struct size
but used AF_XDP (0x2C) instead of AF_CAN (0x1D) in the address family
field:
bind$xdp(r2, &(0x7f0000000540)={0x2c, 0x0, r4, 0x0, r2}, 0x10)
^^^^
This has no funtional impact but the userspace should be notified about
the wrong address family field content.
ext4: guard against EA inode refcount underflow in xattr update
In the Linux kernel, the following vulnerability has been resolved:
ext4: guard against EA inode refcount underflow in xattr update
syzkaller found a path where ext4_xattr_inode_update_ref() reads an EA
inode refcount that is already <= 0 and then applies ref_change (often
-1). That lets the refcount underflow and we proceed with a bogus value,
triggering errors like:
EXT4-fs error: EA inode <n> ref underflow: ref_count=-1 ref_change=-1
EXT4-fs warning: ea_inode dec ref err=-117
Make the invariant explicit: if the current refcount is non-positive,
treat this as on-disk corruption, emit ext4_error_inode(), and fail the
operation with -
wifi: brcmfmac: Fix potential shift-out-of-bounds in brcmf_fw_alloc_request()
In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: Fix potential shift-out-of-bounds in brcmf_fw_alloc_request()
This patch fixes a shift-out-of-bounds in brcmfmac that occurs in
BIT(chiprev) when a 'chiprev' provided by the device is too large.
It should also not be equal to or greater than BITS_PER_TYPE(u32)
as we do bitwise AND with a u32 variable and BIT(chiprev). The patch
adds a check that makes the function return NULL if that is the case.
Note that the NULL case is later handled by the bus-specific caller,
brcmf_usb_probe_cb() or brcmf_usb_reset_resume(), for example.
Found by a modified version of
In the Linux kernel, the following vulnerability has been resolved:
x86: fix clear_user_rep_good() exception handling annotation
This code no longer exists in mainline, because it was removed in
commit d2c95f9d6802 ("x86: don't use REP_GOOD or ERMS for user memory
clearing") upstream.
However, rather than backport the full range of x86 memory clearing and
copying cleanups, fix the exception table annotation placement for the
final 'rep movsb' in clear_user_rep_good(): rather than pointing at the
actual instruction that did the user space access, it pointed to the
register move just before it.
That made sense from a code flow standpoint, b
mm: /proc/pid/smaps_rollup: fix no vma's null-deref
In the Linux kernel, the following vulnerability has been resolved:
mm: /proc/pid/smaps_rollup: fix no vma's null-deref
Commit 258f669e7e88 ("mm: /proc/pid/smaps_rollup: convert to single value
seq_file") introduced a null-deref if there are no vma's in the task in
show_smaps_rollup.
In the Linux kernel, the following vulnerability has been resolved:
android: binder: stop saving a pointer to the VMA
Do not record a pointer to a VMA outside of the mmap_lock for later use.
This is unsafe and there are a number of failure paths *after* the
recorded VMA pointer may be freed during setup. There is no callback to
the driver to clear the saved pointer from generic mm code. Furthermore,
the VMA pointer may become stale if any number of VMA operations end up
freeing the VMA so saving it was fragile to being with.
Instead, change the binder_alloc struct to record the start address of the
VMA and use vma_lookup() to get the vm
In the Linux kernel, the following vulnerability has been resolved:
arm64: set UXN on swapper page tables
[ This issue was fixed upstream by accident in c3cee924bd85 ("arm64:
head: cover entire kernel image in initial ID map") as part of a
large refactoring of the arm64 boot flow. This simple fix is therefore
preferred for -stable backporting ]
On a system that implements FEAT_EPAN, read/write access to the idmap
is denied because UXN is not set on the swapper PTEs. As a result,
idmap_kpti_install_ng_mappings panics the kernel when accessing
__idmap_kpti_flag. Fix it by setting UXN on these PTEs.
In the Linux kernel, the following vulnerability has been resolved:
arm64: set UXN on swapper page tables
[ This issue was fixed upstream by accident in c3cee924bd85 ("arm64:
head: cover entire kernel image in initial ID map") as part of a
large refactoring of the arm64 boot flow. This simple fix is therefore
preferred for -stable backporting ]
On a system that implements FEAT_EPAN, read/write access to the idmap
is denied because UXN is not set on the swapper PTEs. As a result,
idmap_kpti_install_ng_mappings panics the kernel when accessing
__idmap_kpti_flag. Fix it by setting UXN on these PTEs.
btrfs: replace BTRFS_MAX_EXTENT_SIZE with fs_info->max_extent_size
In the Linux kernel, the following vulnerability has been resolved:
btrfs: replace BTRFS_MAX_EXTENT_SIZE with fs_info->max_extent_size
On zoned filesystem, data write out is limited by max_zone_append_size,
and a large ordered extent is split according the size of a bio. OTOH,
the number of extents to be written is calculated using
BTRFS_MAX_EXTENT_SIZE, and that estimated number is used to reserve the
metadata bytes to update and/or create the metadata items.
The metadata reservation is done at e.g, btrfs_buffered_write() and then
released according to the estimation changes. Thus, if the number of extent
increases massively, the reserved
tty: n_gsm: add sanity check for gsm->receive in gsm_receive_buf()
In the Linux kernel, the following vulnerability has been resolved:
tty: n_gsm: add sanity check for gsm->receive in gsm_receive_buf()
A null pointer dereference can happen when attempting to access the
"gsm->receive()" function in gsmld_receive_buf(). Currently, the code
assumes that gsm->recieve is only called after MUX activation.
Since the gsmld_receive_buf() function can be accessed without the need to
initialize the MUX, the gsm->receive() function will not be set and a
NULL pointer dereference will occur.
Fix this by avoiding the call to "gsm->receive()" in case the function is
not initialized by adding a sanity check.
Call Trace:
Incorrect execution-assigned permissions in the Linux kernel mode driver for the Intel(R) 800 Series Ethernet Driver before version 1.15.4 may allow an authenticated user to potentially enable information disclosure via local access.
iommu/arm-smmu: Defer probe of clients after smmu device bound
In the Linux kernel, the following vulnerability has been resolved:
iommu/arm-smmu: Defer probe of clients after smmu device bound
Null pointer dereference occurs due to a race between smmu
driver probe and client driver probe, when of_dma_configure()
for client is called after the iommu_device_register() for smmu driver
probe has executed but before the driver_bound() for smmu driver
has been called.
Following is how the race occurs:
T1:Smmu device probe T2: Client device probe
really_probe()
arm_smmu_device_probe()
iommu_device_register()
really_probe()
platform_dma_configure()
of_dma_configure()
of_dma_configure_i
In the Linux kernel, the following vulnerability has been resolved:
nfsd: release svc_expkey/svc_export with rcu_work
The last reference for `cache_head` can be reduced to zero in `c_show`
and `e_show`(using `rcu_read_lock` and `rcu_read_unlock`). Consequently,
`svc_export_put` and `expkey_put` will be invoked, leading to two
issues:
1. The `svc_export_put` will directly free ex_uuid. However,
`e_show`/`c_show` will access `ex_uuid` after `cache_put`, which can
trigger a use-after-free issue, shown below.
==================================================================
BUG: KASAN: slab-use-after-free in svc_export_show+0x362
bpf: Fix crash due to out of bounds access into reg2btf_ids.
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix crash due to out of bounds access into reg2btf_ids.
When commit e6ac2450d6de ("bpf: Support bpf program calling kernel function") added
kfunc support, it defined reg2btf_ids as a cheap way to translate the verifier
reg type to the appropriate btf_vmlinux BTF ID, however
commit c25b2ae13603 ("bpf: Replace PTR_TO_XXX_OR_NULL with PTR_TO_XXX | PTR_MAYBE_NULL")
moved the __BPF_REG_TYPE_MAX from the last member of bpf_reg_type enum to after
the base register types, and defined other variants using type flag
composition. However, now, the direct usage of reg->type to ind
block: release rq qos structures for queue without disk
In the Linux kernel, the following vulnerability has been resolved:
block: release rq qos structures for queue without disk
blkcg_init_queue() may add rq qos structures to request queue, previously
blk_cleanup_queue() calls rq_qos_exit() to release them, but commit
8e141f9eb803 ("block: drain file system I/O on del_gendisk")
moves rq_qos_exit() into del_gendisk(), so memory leak is caused
because queues may not have disk, such as un-present scsi luns, nvme
admin queue, ...
Fixes the issue by adding rq_qos_exit() to blk_cleanup_queue() back.
BTW, v5.18 won't need this patch any more since we move
blkcg_init_queue()/blkcg_exit_queue() into
In the Linux kernel, the following vulnerability has been resolved:
tracing: Have trace_event_file have ref counters
The following can crash the kernel:
# cd /sys/kernel/tracing
# echo 'p:sched schedule' > kprobe_events
# exec 5>>events/kprobes/sched/enable
# > kprobe_events
# exec 5>&-
The above commands:
1. Change directory to the tracefs directory
2. Create a kprobe event (doesn't matter what one)
3. Open bash file descriptor 5 on the enable file of the kprobe event
4. Delete the kprobe event (removes the files too)
5. Close the bash file descriptor 5
The above causes a crash!
BUG: kernel NULL pointer dereference, address