Archivos mensuales: enero 2025

In the Linux kernel, the following vulnerability has been resolved:

gve: guard XDP xmit NDO on existence of xdp queues

In GVE, dedicated XDP queues only exist when an XDP program is installed
and the interface is up. As such, the NDO XDP XMIT callback should
return early if either of these conditions are false.

In the case of no loaded XDP program, priv->num_xdp_queues=0 which can
cause a divide-by-zero error, and in the case of interface down,
num_xdp_queues remains untouched to persist XDP queue count for the next
interface up, but the TX pointer itself would be NULL.

The XDP xmit callback also needs to synchronize with a device
transitioning from open to close. This synchronization will happen via
the GVE_PRIV_FLAGS_NAPI_ENABLED bit along with a synchronize_net() call,
which waits for any RCU critical sections at call-time to complete.

In the Linux kernel, the following vulnerability has been resolved:

selinux: ignore unknown extended permissions

When evaluating extended permissions, ignore unknown permissions instead
of calling BUG(). This commit ensures that future permissions can be
added without interfering with older kernels.

Input validation vulnerability in Qualifio's Wheel of Fortune. This vulnerability allows an attacker to modify an email to contain the ‘+’ symbol to access the application and win prizes as many times as wanted.

Input validation vulnerability in Qualifio's Wheel of Fortune. This vulnerability could allow an attacker to modify a single email to contain upper and lower case characters in order to access the application and win prizes as many times as wanted.

In the Linux kernel, the following vulnerability has been resolved:

net/sctp: Prevent autoclose integer overflow in sctp_association_init()

While by default max_autoclose equals to INT_MAX / HZ, one may set
net.sctp.max_autoclose to UINT_MAX. There is code in
sctp_association_init() that can consequently trigger overflow.

In the Linux kernel, the following vulnerability has been resolved:

mm: reinstate ability to map write-sealed memfd mappings read-only

Patch series "mm: reinstate ability to map write-sealed memfd mappings
read-only".

In commit 158978945f31 ("mm: perform the mapping_map_writable() check
after call_mmap()") (and preceding changes in the same series) it became
possible to mmap() F_SEAL_WRITE sealed memfd mappings read-only.

Commit 5de195060b2e ("mm: resolve faulty mmap_region() error path
behaviour") unintentionally undid this logic by moving the
mapping_map_writable() check before the shmem_mmap() hook is invoked,
thereby regressing this change.

This series reworks how we both permit write-sealed mappings being mapped
read-only and disallow mprotect() from undoing the write-seal, fixing this
regression.

We also add a regression test to ensure that we do not accidentally
regress this in future.

Thanks to Julian Orth for reporting this regression.

This patch (of 2):

In commit 158978945f31 ("mm: perform the mapping_map_writable() check
after call_mmap()") (and preceding changes in the same series) it became
possible to mmap() F_SEAL_WRITE sealed memfd mappings read-only.

This was previously unnecessarily disallowed, despite the man page
documentation indicating that it would be, thereby limiting the usefulness
of F_SEAL_WRITE logic.

We fixed this by adapting logic that existed for the F_SEAL_FUTURE_WRITE
seal (one which disallows future writes to the memfd) to also be used for
F_SEAL_WRITE.

For background – the F_SEAL_FUTURE_WRITE seal clears VM_MAYWRITE for a
read-only mapping to disallow mprotect() from overriding the seal – an
operation performed by seal_check_write(), invoked from shmem_mmap(), the
f_op->mmap() hook used by shmem mappings.

By extending this to F_SEAL_WRITE and critically – checking
mapping_map_writable() to determine if we may map the memfd AFTER we
invoke shmem_mmap() – the desired logic becomes possible. This is because
mapping_map_writable() explicitly checks for VM_MAYWRITE, which we will
have cleared.

Commit 5de195060b2e ("mm: resolve faulty mmap_region() error path
behaviour") unintentionally undid this logic by moving the
mapping_map_writable() check before the shmem_mmap() hook is invoked,
thereby regressing this change.

We reinstate this functionality by moving the check out of shmem_mmap()
and instead performing it in do_mmap() at the point at which VMA flags are
being determined, which seems in any case to be a more appropriate place
in which to make this determination.

In order to achieve this we rework memfd seal logic to allow us access to
this information using existing logic and eliminate the clearing of
VM_MAYWRITE from seal_check_write() which we are performing in do_mmap()
instead.

In the Linux kernel, the following vulnerability has been resolved:

RDMA/bnxt_re: Fix max SGEs for the Work Request

Gen P7 supports up to 13 SGEs for now. WQE software structure
can hold only 6 now. Since the max send sge is reported as
13, the stack can give requests up to 13 SGEs. This is causing
traffic failures and system crashes.

Use the define for max SGE supported for variable size. This
will work for both static and variable WQEs.

In the Linux kernel, the following vulnerability has been resolved:

fgraph: Add READ_ONCE() when accessing fgraph_array[]

In __ftrace_return_to_handler(), a loop iterates over the fgraph_array[]
elements, which are fgraph_ops. The loop checks if an element is a
fgraph_stub to prevent using a fgraph_stub afterward.

However, if the compiler reloads fgraph_array[] after this check, it might
race with an update to fgraph_array[] that introduces a fgraph_stub. This
could result in the stub being processed, but the stub contains a null
"func_hash" field, leading to a NULL pointer dereference.

To ensure that the gops compared against the fgraph_stub matches the gops
processed later, add a READ_ONCE(). A similar patch appears in commit
63a8dfb ("function_graph: Add READ_ONCE() when accessing fgraph_array[]").

In the Linux kernel, the following vulnerability has been resolved:

RDMA/hns: Fix accessing invalid dip_ctx during destroying QP

If it fails to modify QP to RTR, dip_ctx will not be attached. And
during detroying QP, the invalid dip_ctx pointer will be accessed.

On most desktop platforms, Brave Browser versions 1.70.x-1.73.x included a feature to show a site's origin on the OS-provided file selector dialog when a site prompts the user to upload or download a file. However the origin was not correctly inferred in some cases. When combined with an open redirector vulnerability on a trusted site, this could allow a malicious site to initiate a download whose origin in the file select dialog appears as the trusted site which initiated the redirect.