In the Linux kernel, the following vulnerability has been resolved:
drm: amd: display: Fix memory leakage
This commit fixes memory leakage in dc_construct_ctx() function.
In the Linux kernel, the following vulnerability has been resolved:
ipmi_si: fix a memleak in try_smi_init()
Kmemleak reported the following leak info in try_smi_init():
unreferenced object 0xffff00018ecf9400 (size 1024):
comm "modprobe", pid 2707763, jiffies 4300851415 (age 773.308s)
backtrace:
[<000000004ca5b312>] __kmalloc+0x4b8/0x7b0
[<00000000953b1072>] try_smi_init+0x148/0x5dc [ipmi_si]
[<000000006460d325>] 0xffff800081b10148
[<0000000039206ea5>] do_one_initcall+0x64/0x2a4
[<00000000601399ce>] do_init_module+0x50/0x300
[<000000003c12ba3c>] load_module+0x7a8/0x9e0
[<00000000c246fffe>] __se_sys_init_module+0x104/0x180
[<00000000eea99093>] __arm64_sys_init_module+0x24/0x30
[<0000000021b1ef87>] el0_svc_common.constprop.0+0x94/0x250
[<0000000070f4f8b7>] do_el0_svc+0x48/0xe0
[<000000005a05337f>] el0_svc+0x24/0x3c
[<000000005eb248d6>] el0_sync_handler+0x160/0x164
[<0000000030a59039>] el0_sync+0x160/0x180
The problem was that when an error occurred before handlers registration
and after allocating `new_smi->si_sm`, the variable wouldn't be freed in
the error handling afterwards since `shutdown_smi()` hadn't been
registered yet. Fix it by adding a `kfree()` in the error handling path
in `try_smi_init()`.
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (coretemp) Simplify platform device handling
Coretemp's platform driver is unconventional. All the real work is done
globally by the initcall and CPU hotplug notifiers, while the "driver"
effectively just wraps an allocation and the registration of the hwmon
interface in a long-winded round-trip through the driver core. The whole
logic of dynamically creating and destroying platform devices to bring
the interfaces up and down is error prone, since it assumes
platform_device_add() will synchronously bind the driver and set drvdata
before it returns, thus results in a NULL dereference if drivers_autoprobe
is turned off for the platform bus. Furthermore, the unusual approach of
doing that from within a CPU hotplug notifier, already commented in the
code that it deadlocks suspend, also causes lockdep issues for other
drivers or subsystems which may want to legitimately register a CPU
hotplug notifier from a platform bus notifier.
All of these issues can be solved by ripping this unusual behaviour out
completely, simply tying the platform devices to the lifetime of the
module itself, and directly managing the hwmon interfaces from the
hotplug notifiers. There is a slight user-visible change in that
/sys/bus/platform/drivers/coretemp will no longer appear, and
/sys/devices/platform/coretemp.n will remain present if package n is
hotplugged off, but hwmon users should really only be looking for the
presence of the hwmon interfaces, whose behaviour remains unchanged.
In the Linux kernel, the following vulnerability has been resolved:
drivers: base: Free devm resources when unregistering a device
In the current code, devres_release_all() only gets called if the device
has a bus and has been probed.
This leads to issues when using bus-less or driver-less devices where
the device might never get freed if a managed resource holds a reference
to the device. This is happening in the DRM framework for example.
We should thus call devres_release_all() in the device_del() function to
make sure that the device-managed actions are properly executed when the
device is unregistered, even if it has neither a bus nor a driver.
This is effectively the same change than commit 2f8d16a996da ("devres:
release resources on device_del()") that got reverted by commit
a525a3ddeaca ("driver core: free devres in device_release") over
memory leaks concerns.
This patch effectively combines the two commits mentioned above to
release the resources both on device_del() and device_release() and get
the best of both worlds.
In the Linux kernel, the following vulnerability has been resolved:
drm/msm: fix use-after-free on probe deferral
The bridge counter was never reset when tearing down the DRM device so
that stale pointers to deallocated structures would be accessed on the
next tear down (e.g. after a second late bind deferral).
Given enough bridges and a few probe deferrals this could currently also
lead to data beyond the bridge array being corrupted.
Patchwork: https://patchwork.freedesktop.org/patch/502665/
In the Linux kernel, the following vulnerability has been resolved:
ext4: add EXT4_IGET_BAD flag to prevent unexpected bad inode
There are many places that will get unhappy (and crash) when ext4_iget()
returns a bad inode. However, if iget the boot loader inode, allows a bad
inode to be returned, because the inode may not be initialized. This
mechanism can be used to bypass some checks and cause panic. To solve this
problem, we add a special iget flag EXT4_IGET_BAD. Only with this flag
we'd be returning bad inode from ext4_iget(), otherwise we always return
the error code if the inode is bad inode.(suggested by Jan Kara)
In the Linux kernel, the following vulnerability has been resolved:
xen/gntdev: Accommodate VMA splitting
Prior to this commit, the gntdev driver code did not handle the
following scenario correctly with paravirtualized (PV) Xen domains:
* User process sets up a gntdev mapping composed of two grant mappings
(i.e., two pages shared by another Xen domain).
* User process munmap()s one of the pages.
* User process munmap()s the remaining page.
* User process exits.
In the scenario above, the user process would cause the kernel to log
the following messages in dmesg for the first munmap(), and the second
munmap() call would result in similar log messages:
BUG: Bad page map in process doublemap.test pte:... pmd:...
page:0000000057c97bff refcount:1 mapcount:-1 \
mapping:0000000000000000 index:0x0 pfn:...
...
page dumped because: bad pte
...
file:gntdev fault:0x0 mmap:gntdev_mmap [xen_gntdev] readpage:0x0
...
Call Trace:
<TASK>
dump_stack_lvl+0x46/0x5e
print_bad_pte.cold+0x66/0xb6
unmap_page_range+0x7e5/0xdc0
unmap_vmas+0x78/0xf0
unmap_region+0xa8/0x110
__do_munmap+0x1ea/0x4e0
__vm_munmap+0x75/0x120
__x64_sys_munmap+0x28/0x40
do_syscall_64+0x38/0x90
entry_SYSCALL_64_after_hwframe+0x61/0xcb
...
For each munmap() call, the Xen hypervisor (if built with CONFIG_DEBUG)
would print out the following and trigger a general protection fault in
the affected Xen PV domain:
(XEN) d0v... Attempt to implicitly unmap d0's grant PTE ...
(XEN) d0v... Attempt to implicitly unmap d0's grant PTE ...
As of this writing, gntdev_grant_map structure's vma field (referred to
as map->vma below) is mainly used for checking the start and end
addresses of mappings. However, with split VMAs, these may change, and
there could be more than one VMA associated with a gntdev mapping.
Hence, remove the use of map->vma and rely on map->pages_vm_start for
the original start address and on (map->count << PAGE_SHIFT) for the
original mapping size. Let the invalidate() and find_special_page()
hooks use these.
Also, given that there can be multiple VMAs associated with a gntdev
mapping, move the "mmu_interval_notifier_remove(&map->notifier)" call to
the end of gntdev_put_map, so that the MMU notifier is only removed
after the closing of the last remaining VMA.
Finally, use an atomic to prevent inadvertent gntdev mapping re-use,
instead of using the map->live_grants atomic counter and/or the map->vma
pointer (the latter of which is now removed). This prevents the
userspace from mmap()'ing (with MAP_FIXED) a gntdev mapping over the
same address range as a previously set up gntdev mapping. This scenario
can be summarized with the following call-trace, which was valid prior
to this commit:
mmap
gntdev_mmap
mmap (repeat mmap with MAP_FIXED over the same address range)
gntdev_invalidate
unmap_grant_pages (sets 'being_removed' entries to true)
gnttab_unmap_refs_async
unmap_single_vma
gntdev_mmap (maps the shared pages again)
munmap
gntdev_invalidate
unmap_grant_pages
(no-op because 'being_removed' entries are true)
unmap_single_vma (For PV domains, Xen reports that a granted page
is being unmapped and triggers a general protection fault in the
affected domain, if Xen was built with CONFIG_DEBUG)
The fix for this last scenario could be worth its own commit, but we
opted for a single commit, because removing the gntdev_grant_map
structure's vma field requires guarding the entry to gntdev_mmap(), and
the live_grants atomic counter is not sufficient on its own to prevent
the mmap() over a pre-existing mapping.
In the Linux kernel, the following vulnerability has been resolved:
qed: Don't collect too many protection override GRC elements
In the protection override dump path, the firmware can return far too
many GRC elements, resulting in attempting to write past the end of the
previously-kmalloc'ed dump buffer.
This will result in a kernel panic with reason:
BUG: unable to handle kernel paging request at ADDRESS
where "ADDRESS" is just past the end of the protection override dump
buffer. The start address of the buffer is:
p_hwfn->cdev->dbg_features[DBG_FEATURE_PROTECTION_OVERRIDE].dump_buf
and the size of the buffer is buf_size in the same data structure.
The panic can be arrived at from either the qede Ethernet driver path:
[exception RIP: qed_grc_dump_addr_range+0x108]
qed_protection_override_dump at ffffffffc02662ed [qed]
qed_dbg_protection_override_dump at ffffffffc0267792 [qed]
qed_dbg_feature at ffffffffc026aa8f [qed]
qed_dbg_all_data at ffffffffc026b211 [qed]
qed_fw_fatal_reporter_dump at ffffffffc027298a [qed]
devlink_health_do_dump at ffffffff82497f61
devlink_health_report at ffffffff8249cf29
qed_report_fatal_error at ffffffffc0272baf [qed]
qede_sp_task at ffffffffc045ed32 [qede]
process_one_work at ffffffff81d19783
or the qedf storage driver path:
[exception RIP: qed_grc_dump_addr_range+0x108]
qed_protection_override_dump at ffffffffc068b2ed [qed]
qed_dbg_protection_override_dump at ffffffffc068c792 [qed]
qed_dbg_feature at ffffffffc068fa8f [qed]
qed_dbg_all_data at ffffffffc0690211 [qed]
qed_fw_fatal_reporter_dump at ffffffffc069798a [qed]
devlink_health_do_dump at ffffffff8aa95e51
devlink_health_report at ffffffff8aa9ae19
qed_report_fatal_error at ffffffffc0697baf [qed]
qed_hw_err_notify at ffffffffc06d32d7 [qed]
qed_spq_post at ffffffffc06b1011 [qed]
qed_fcoe_destroy_conn at ffffffffc06b2e91 [qed]
qedf_cleanup_fcport at ffffffffc05e7597 [qedf]
qedf_rport_event_handler at ffffffffc05e7bf7 [qedf]
fc_rport_work at ffffffffc02da715 [libfc]
process_one_work at ffffffff8a319663
Resolve this by clamping the firmware's return value to the maximum
number of legal elements the firmware should return.