Security Vulnerabilities - CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix rxrpc_local leak in rxrpc_lookup_peer()
Need to call rxrpc_put_local() for peer candidate before kfree() as it
holds a ref to rxrpc_local.
[DH: v2: Changed to abstract the peer freeing code out into a function]
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix rxrpc_peer leak in rxrpc_look_up_bundle()
Need to call rxrpc_put_peer() for bundle candidate before kfree() as it
holds a ref to rxrpc_peer.
[DH: v2: Changed to abstract out the bundle freeing code into a function]
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
drm/msm: Fix wait_fence submitqueue leak
We weren't dropping the submitqueue reference in all paths. In
particular, when the fence has already been signalled. Split out
a helper to simplify handling this in the various different return
paths.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
drm/msm: Fix mmap to include VM_IO and VM_DONTDUMP
In commit 510410bfc034 ("drm/msm: Implement mmap as GEM object
function") we switched to a new/cleaner method of doing things. That's
good, but we missed a little bit.
Before that commit, we used to _first_ run through the
drm_gem_mmap_obj() case where `obj->funcs->mmap()` was NULL. That meant
that we ran:
vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
...and _then_ we modified those mappings with our own. Now that
`obj->funcs->mmap()` is no longer NULL we don't run the default
code. It looks like the fact that the vm_flags got VM_IO / VM_DONTDUMP
was important because we're now getting crashes on Chromebooks that
use ARC++ while logging out. Specifically a crash that looks like this
(this is on a 5.10 kernel w/ relevant backports but also seen on a
5.15 kernel):
Unable to handle kernel paging request at virtual address ffffffc008000000
Mem abort info:
ESR = 0x96000006
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
Data abort info:
ISV = 0, ISS = 0x00000006
CM = 0, WnR = 0
swapper pgtable: 4k pages, 39-bit VAs, pgdp=000000008293d000
[ffffffc008000000] pgd=00000001002b3003, p4d=00000001002b3003,
pud=00000001002b3003, pmd=0000000000000000
Internal error: Oops: 96000006 [#1] PREEMPT SMP
[...]
CPU: 7 PID: 15734 Comm: crash_dump64 Tainted: G W 5.10.67 #1 [...]
Hardware name: Qualcomm Technologies, Inc. sc7280 IDP SKU2 platform (DT)
pstate: 80400009 (Nzcv daif +PAN -UAO -TCO BTYPE=--)
pc : __arch_copy_to_user+0xc0/0x30c
lr : copyout+0xac/0x14c
[...]
Call trace:
__arch_copy_to_user+0xc0/0x30c
copy_page_to_iter+0x1a0/0x294
process_vm_rw_core+0x240/0x408
process_vm_rw+0x110/0x16c
__arm64_sys_process_vm_readv+0x30/0x3c
el0_svc_common+0xf8/0x250
do_el0_svc+0x30/0x80
el0_svc+0x10/0x1c
el0_sync_handler+0x78/0x108
el0_sync+0x184/0x1c0
Code: f8408423 f80008c3 910020c6 36100082 (b8404423)
Let's add the two flags back in.
While we're at it, the fact that we aren't running the default means
that we _don't_ need to clear out VM_PFNMAP, so remove that and save
an instruction.
NOTE: it was confirmed that VM_IO was the important flag to fix the
problem I was seeing, but adding back VM_DONTDUMP seems like a sane
thing to do so I'm doing that too.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
drm/msm/devfreq: Fix OPP refcnt leak
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
drm/vc4: kms: Clear the HVS FIFO commit pointer once done
Commit 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a
commit") introduced a wait on the previous commit done on a given HVS
FIFO.
However, we never cleared that pointer once done. Since
drm_crtc_commit_put can free the drm_crtc_commit structure directly if
we were the last user, this means that it can lead to a use-after free
if we were to duplicate the state, and that stale pointer would even be
copied to the new state.
Set the pointer to NULL once we're done with the wait so that we don't
carry over a pointer to a free'd structure.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
drm/vc4: kms: Add missing drm_crtc_commit_put
Commit 9ec03d7f1ed3 ("drm/vc4: kms: Wait on previous FIFO users before a
commit") introduced a global state for the HVS, with each FIFO storing
the current CRTC commit so that we can properly synchronize commits.
However, the refcounting was off and we thus ended up leaking the
drm_crtc_commit structure every commit. Add a drm_crtc_commit_put to
prevent the leakage.
CVSS Score
4.1
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
serial: liteuart: fix use-after-free and memleak on unbind
Deregister the port when unbinding the driver to prevent it from being
used after releasing the driver data and leaking memory allocated by
serial core.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
serial: liteuart: Fix NULL pointer dereference in ->remove()
drvdata has to be set in _probe() - otherwise platform_get_drvdata()
causes null pointer dereference BUG in _remove().
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24
In the Linux kernel, the following vulnerability has been resolved:
serial: core: fix transmit-buffer reset and memleak
Commit 761ed4a94582 ("tty: serial_core: convert uart_close to use
tty_port_close") converted serial core to use tty_port_close() but
failed to notice that the transmit buffer still needs to be freed on
final close.
Not freeing the transmit buffer means that the buffer is no longer
cleared on next open so that any ioctl() waiting for the buffer to drain
might wait indefinitely (e.g. on termios changes) or that stale data can
end up being transmitted in case tx is restarted.
Furthermore, the buffer of any port that has been opened would leak on
driver unbind.
Note that the port lock is held when clearing the buffer pointer due to
the ldisc race worked around by commit a5ba1d95e46e ("uart: fix race
between uart_put_char() and uart_shutdown()").
Also note that the tty-port shutdown() callback is not called for
console ports so it is not strictly necessary to free the buffer page
after releasing the lock (cf. d72402145ace ("tty/serial: do not free
trasnmit buffer page under port lock")).
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-24