Linux Linux Kernel 2.3.23

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

drm/amdgpu/mes: fix mes ring buffer overflow

wait memory room until enough before writing mes packets to avoid ring buffer overflow.

v2: squash in sched_hw_submission fix

(cherry picked from commit 34e087e8920e635c62e2ed6a758b0cd27f836d13)

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

drm/v3d: Disable preemption while updating GPU stats

We forgot to disable preemption around the write_seqcount_begin/end() pair while updating GPU stats:

[ ] WARNING: CPU: 2 PID: 12 at include/linux/seqlock.h:221 __seqprop_assert.isra.0+0x128/0x150 [v3d]
[ ] Workqueue: v3d_bin drm_sched_run_job_work [gpu_sched]
<...snip...>
[ ] Call trace:
[ ] __seqprop_assert.isra.0+0x128/0x150 [v3d]
[ ] v3d_job_start_stats.isra.0+0x90/0x218 [v3d]
[ ] v3d_bin_job_run+0x23c/0x388 [v3d]
[ ] drm_sched_run_job_work+0x520/0x6d0 [gpu_sched]
[ ] process_one_work+0x62c/0xb48
[ ] worker_thread+0x468/0x5b0
[ ] kthread+0x1c4/0x1e0
[ ] ret_from_fork+0x10/0x20

Fix it.

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

video/aperture: optionally match the device in sysfb_disable()

In aperture_remove_conflicting_pci_devices(), we currently only call sysfb_disable() on vga class devices. This leads to the following problem when the pimary device is not VGA compatible:

1. A PCI device with a non-VGA class is the boot display 2. That device is probed first and it is not a VGA device so
sysfb_disable() is not called, but the device resources
are freed by aperture_detach_platform_device() 3. Non-primary GPU has a VGA class and it ends up calling sysfb_disable() 4. NULL pointer dereference via sysfb_disable() since the resources
have already been freed by aperture_detach_platform_device() when
it was called by the other device.

Fix this by passing a device pointer to sysfb_disable() and checking the device to determine if we should execute it or not.

v2: Fix build when CONFIG_SCREEN_INFO is not set v3: Move device check into the mutex
Drop primary variable in aperture_remove_conflicting_pci_devices()
Drop __init on pci sysfb_pci_dev_is_enabled()

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

nfsd: fix potential UAF in nfsd4_cb_getattr_release

Once we drop the delegation reference, the fields embedded in it are no longer safe to access. Do that last.

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

soc: qcom: pmic_glink: Fix race during initialization

As pointed out by Stephen Boyd it is possible that during initialization of the pmic_glink child drivers, the protection-domain notifiers fires, and the associated work is scheduled, before the client registration returns and as a result the local "client" pointer has been initialized.

The outcome of this is a NULL pointer dereference as the "client" pointer is blindly dereferenced.

Timeline provided by Stephen:
CPU0 CPU1
---- ----
ucsi->client = NULL;
devm_pmic_glink_register_client()
client->pdr_notify(client->priv, pg->client_state)
pmic_glink_ucsi_pdr_notify()
schedule_work(&ucsi->register_work)

pmic_glink_ucsi_register()
ucsi_register()
pmic_glink_ucsi_read_version()
pmic_glink_ucsi_read()
pmic_glink_ucsi_read()
pmic_glink_send(ucsi->client)

ucsi->client = client // Too late!

This code is identical across the altmode, battery manager and usci child drivers.

Resolve this by splitting the allocation of the "client" object and the registration thereof into two operations.

This only happens if the protection domain registry is populated at the time of registration, which by the introduction of commit '1ebcde047c54 ("soc: qcom: add pd-mapper implementation")' became much more likely.

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

firmware: qcom: scm: Mark get_wq_ctx() as atomic call

Currently get_wq_ctx() is wrongly configured as a standard call. When two SMC calls are in sleep and one SMC wakes up, it calls get_wq_ctx() to resume the corresponding sleeping thread. But if get_wq_ctx() is interrupted, goes to sleep and another SMC call is waiting to be allocated a waitq context, it leads to a deadlock.

To avoid this get_wq_ctx() must be an atomic call and can't be a standard SMC call. Hence mark get_wq_ctx() as a fast call.

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

usb: typec: ucsi: Move unregister out of atomic section

Commit '9329933699b3 ("soc: qcom: pmic_glink: Make client-lock non-sleeping")' moved the pmic_glink client list under a spinlock, as it is accessed by the rpmsg/glink callback, which in turn is invoked from IRQ context.

This means that ucsi_unregister() is now called from atomic context, which isn't feasible as it's expecting a sleepable context. An effort is under way to get GLINK to invoke its callbacks in a sleepable context, but until then lets schedule the unregistration.

A side effect of this is that ucsi_unregister() can now happen after the remote processor, and thereby the communication link with it, is gone. pmic_glink_send() is amended with a check to avoid the resulting NULL pointer dereference. This does however result in the user being informed about this error by the following entry in the kernel log:

ucsi_glink.pmic_glink_ucsi pmic_glink.ucsi.0: failed to send UCSI write request: -5

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

btrfs: fix a use-after-free when hitting errors inside btrfs_submit_chunk()

[BUG] There is an internal report that KASAN is reporting use-after-free, with the following backtrace:

BUG: KASAN: slab-use-after-free in btrfs_check_read_bio+0xa68/0xb70 [btrfs]
Read of size 4 at addr ffff8881117cec28 by task kworker/u16:2/45
CPU: 1 UID: 0 PID: 45 Comm: kworker/u16:2 Not tainted 6.11.0-rc2-next-20240805-default+ #76
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
Workqueue: btrfs-endio btrfs_end_bio_work [btrfs]
Call Trace:
dump_stack_lvl+0x61/0x80
print_address_description.constprop.0+0x5e/0x2f0
print_report+0x118/0x216
kasan_report+0x11d/0x1f0
btrfs_check_read_bio+0xa68/0xb70 [btrfs]
process_one_work+0xce0/0x12a0
worker_thread+0x717/0x1250
kthread+0x2e3/0x3c0
ret_from_fork+0x2d/0x70
ret_from_fork_asm+0x11/0x20

Allocated by task 20917:
kasan_save_stack+0x37/0x60
kasan_save_track+0x10/0x30
__kasan_slab_alloc+0x7d/0x80
kmem_cache_alloc_noprof+0x16e/0x3e0
mempool_alloc_noprof+0x12e/0x310
bio_alloc_bioset+0x3f0/0x7a0
btrfs_bio_alloc+0x2e/0x50 [btrfs]
submit_extent_page+0x4d1/0xdb0 [btrfs]
btrfs_do_readpage+0x8b4/0x12a0 [btrfs]
btrfs_readahead+0x29a/0x430 [btrfs]
read_pages+0x1a7/0xc60
page_cache_ra_unbounded+0x2ad/0x560
filemap_get_pages+0x629/0xa20
filemap_read+0x335/0xbf0
vfs_read+0x790/0xcb0
ksys_read+0xfd/0x1d0
do_syscall_64+0x6d/0x140
entry_SYSCALL_64_after_hwframe+0x4b/0x53

Freed by task 20917:
kasan_save_stack+0x37/0x60
kasan_save_track+0x10/0x30
kasan_save_free_info+0x37/0x50
__kasan_slab_free+0x4b/0x60
kmem_cache_free+0x214/0x5d0
bio_free+0xed/0x180
end_bbio_data_read+0x1cc/0x580 [btrfs]
btrfs_submit_chunk+0x98d/0x1880 [btrfs]
btrfs_submit_bio+0x33/0x70 [btrfs]
submit_one_bio+0xd4/0x130 [btrfs]
submit_extent_page+0x3ea/0xdb0 [btrfs]
btrfs_do_readpage+0x8b4/0x12a0 [btrfs]
btrfs_readahead+0x29a/0x430 [btrfs]
read_pages+0x1a7/0xc60
page_cache_ra_unbounded+0x2ad/0x560
filemap_get_pages+0x629/0xa20
filemap_read+0x335/0xbf0
vfs_read+0x790/0xcb0
ksys_read+0xfd/0x1d0
do_syscall_64+0x6d/0x140
entry_SYSCALL_64_after_hwframe+0x4b/0x53

[CAUSE] Although I cannot reproduce the error, the report itself is good enough to pin down the cause.

The call trace is the regular endio workqueue context, but the free-by-task trace is showing that during btrfs_submit_chunk() we already hit a critical error, and is calling btrfs_bio_end_io() to error out. And the original endio function called bio_put() to free the whole bio.

This means a double freeing thus causing use-after-free, e.g.:

1. Enter btrfs_submit_bio() with a read bio
The read bio length is 128K, crossing two 64K stripes.

2. The first run of btrfs_submit_chunk()

2.1 Call btrfs_map_block(), which returns 64K 2.2 Call btrfs_split_bio()
Now there are two bios, one referring to the first 64K, the other
referring to the second 64K. 2.3 The first half is submitted.

3. The second run of btrfs_submit_chunk()

3.1 Call btrfs_map_block(), which by somehow failed
Now we call btrfs_bio_end_io() to handle the error

3.2 btrfs_bio_end_io() calls the original endio function
Which is end_bbio_data_read(), and it calls bio_put() for the
original bio.

Now the original bio is freed.

4. The submitted first 64K bio finished
Now we call into btrfs_check_read_bio() and tries to advance the bio
iter.
But since the original bio (thus its iter) is already freed, we
trigger the above use-after free.

And even if the memory is not poisoned/corrupted, we will later call
the original endio function, causing a double freeing.

[FIX] Instead of calling btrfs_bio_end_io(), call btrfs_orig_bbio_end_io(), which has the extra check on split bios and do the pr ---truncated---

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

smb/client: avoid dereferencing rdata=NULL in smb2_new_read_req()

This happens when called from SMB2_read() while using rdma and reaching the rdma_readwrite_threshold.

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

pinctrl: single: fix potential NULL dereference in pcs_get_function()

pinmux_generic_get_function() can return NULL and the pointer 'function' was dereferenced without checking against NULL. Add checking of pointer 'function' in pcs_get_function().

Found by code review.

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

drm/xe: prevent UAF around preempt fence

The fence lock is part of the queue, therefore in the current design anything locking the fence should then also hold a ref to the queue to prevent the queue from being freed.

However, currently it looks like we signal the fence and then drop the queue ref, but if something is waiting on the fence, the waiter is kicked to wake up at some later point, where upon waking up it first grabs the lock before checking the fence state. But if we have already dropped the queue ref, then the lock might already be freed as part of the queue, leading to uaf.

To prevent this, move the fence lock into the fence itself so we don't run into lifetime issues. Alternative might be to have device level lock, or only release the queue in the fence release callback, however that might require pushing to another worker to avoid locking issues.

References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2454 References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2342 References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2020 (cherry picked from commit 7116c35aacedc38be6d15bd21b2fc936eed0008b)

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

nfsd: prevent panic for nfsv4.0 closed files in nfs4_show_open

Prior to commit 3f29cc82a84c ("nfsd: split sc_status out of sc_type") states_show() relied on sc_type field to be of valid type before calling into a subfunction to show content of a particular stateid. From that commit, we split the validity of the stateid into sc_status and no longer changed sc_type to 0 while unhashing the stateid. This resulted in kernel oopsing for nfsv4.0 opens that stay around and in nfs4_show_open() would derefence sc_file which was NULL.

Instead, for closed open stateids forgo displaying information that relies of having a valid sc_file.

To reproduce: mount the server with 4.0, read and close a file and then on the server cat /proc/fs/nfsd/clients/2/states

[ 513.590804] Call trace: [ 513.590925] _raw_spin_lock+0xcc/0x160 [ 513.591119] nfs4_show_open+0x78/0x2c0 [nfsd] [ 513.591412] states_show+0x44c/0x488 [nfsd] [ 513.591681] seq_read_iter+0x5d8/0x760 [ 513.591896] seq_read+0x188/0x208 [ 513.592075] vfs_read+0x148/0x470 [ 513.592241] ksys_read+0xcc/0x178

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

gtp: fix a potential NULL pointer dereference

When sockfd_lookup() fails, gtp_encap_enable_socket() returns a NULL pointer, but its callers only check for error pointers thus miss the NULL pointer case.

Fix it by returning an error pointer with the error code carried from sockfd_lookup().

(I found this bug during code inspection.)

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

usb: dwc3: st: fix probed platform device ref count on probe error path

The probe function never performs any paltform device allocation, thus error path "undo_platform_dev_alloc" is entirely bogus. It drops the reference count from the platform device being probed. If error path is triggered, this will lead to unbalanced device reference counts and premature release of device resources, thus possible use-after-free when releasing remaining devm-managed resources.

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

scsi: aacraid: Fix double-free on probe failure

aac_probe_one() calls hardware-specific init functions through the aac_driver_ident::init pointer, all of which eventually call down to aac_init_adapter().

If aac_init_adapter() fails after allocating memory for aac_dev::queues, it frees the memory but does not clear that member.

After the hardware-specific init function returns an error, aac_probe_one() goes down an error path that frees the memory pointed to by aac_dev::queues, resulting.in a double-free.

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

wifi: brcmfmac: cfg80211: Handle SSID based pmksa deletion

wpa_supplicant 2.11 sends since 1efdba5fdc2c ("Handle PMKSA flush in the driver for SAE/OWE offload cases") SSID based PMKSA del commands. brcmfmac is not prepared and tries to dereference the NULL bssid and pmkid pointers in cfg80211_pmksa. PMKID_V3 operations support SSID based updates so copy the SSID.

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

igb: cope with large MAX_SKB_FRAGS

Sabrina reports that the igb driver does not cope well with large MAX_SKB_FRAG values: setting MAX_SKB_FRAG to 45 causes payload corruption on TX.

An easy reproducer is to run ssh to connect to the machine. With MAX_SKB_FRAGS=17 it works, with MAX_SKB_FRAGS=45 it fails. This has been reported originally in https://bugzilla.redhat.com/show_bug.cgi?id=2265320

The root cause of the issue is that the driver does not take into account properly the (possibly large) shared info size when selecting the ring layout, and will try to fit two packets inside the same 4K page even when the 1st fraglist will trump over the 2nd head.

Address the issue by checking if 2K buffers are insufficient.

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

i2c: tegra: Do not mark ACPI devices as irq safe

On ACPI machines, the tegra i2c module encounters an issue due to a mutex being called inside a spinlock. This leads to the following bug:

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:585
...

Call trace:
__might_sleep
__mutex_lock_common
mutex_lock_nested
acpi_subsys_runtime_resume
rpm_resume
tegra_i2c_xfer

The problem arises because during __pm_runtime_resume(), the spinlock &dev->power.lock is acquired before rpm_resume() is called. Later, rpm_resume() invokes acpi_subsys_runtime_resume(), which relies on mutexes, triggering the error.

To address this issue, devices on ACPI are now marked as not IRQ-safe, considering the dependency of acpi_subsys_runtime_resume() on mutexes.

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

mmc: mmc_test: Fix NULL dereference on allocation failure

If the "test->highmem = alloc_pages()" allocation fails then calling __free_pages(test->highmem) will result in a NULL dereference. Also change the error code to -ENOMEM instead of returning success.

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

usb: xhci: Check for xhci->interrupters being allocated in xhci_mem_clearup()

If xhci_mem_init() fails, it calls into xhci_mem_cleanup() to mop up the damage. If it fails early enough, before xhci->interrupters is allocated but after xhci->max_interrupters has been set, which happens in most (all?) cases, things get uglier, as xhci_mem_cleanup() unconditionally derefences xhci->interrupters. With prejudice.

Gate the interrupt freeing loop with a check on xhci->interrupters being non-NULL.

Found while debugging a DMA allocation issue that led the XHCI driver on this exact path.

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

s390/dasd: fix error recovery leading to data corruption on ESE devices

Extent Space Efficient (ESE) or thin provisioned volumes need to be formatted on demand during usual IO processing.

The dasd_ese_needs_format function checks for error codes that signal the non existence of a proper track format.

The check for incorrect length is to imprecise since other error cases leading to transport of insufficient data also have this flag set. This might lead to data corruption in certain error cases for example during a storage server warmstart.

Fix by removing the check for incorrect length and replacing by explicitly checking for invalid track format in transport mode.

Also remove the check for file protected since this is not a valid ESE handling case.

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

fix bitmap corruption on close_range() with CLOSE_RANGE_UNSHARE

copy_fd_bitmaps(new, old, count) is expected to copy the first count/BITS_PER_LONG bits from old->full_fds_bits[] and fill the rest with zeroes. What it does is copying enough words (BITS_TO_LONGS(count/BITS_PER_LONG)), then memsets the rest. That works fine, *if* all bits past the cutoff point are clear. Otherwise we are risking garbage from the last word we'd copied.

For most of the callers that is true - expand_fdtable() has count equal to old->max_fds, so there's no open descriptors past count, let alone fully occupied words in ->open_fds[], which is what bits in ->full_fds_bits[] correspond to.

The other caller (dup_fd()) passes sane_fdtable_size(old_fdt, max_fds), which is the smallest multiple of BITS_PER_LONG that covers all opened descriptors below max_fds. In the common case (copying on fork()) max_fds is ~0U, so all opened descriptors will be below it and we are fine, by the same reasons why the call in expand_fdtable() is safe.

Unfortunately, there is a case where max_fds is less than that and where we might, indeed, end up with junk in ->full_fds_bits[] - close_range(from, to, CLOSE_RANGE_UNSHARE) with
* descriptor table being currently shared
* 'to' being above the current capacity of descriptor table
* 'from' being just under some chunk of opened descriptors. In that case we end up with observably wrong behaviour - e.g. spawn a child with CLONE_FILES, get all descriptors in range 0..127 open, then close_range(64, ~0U, CLOSE_RANGE_UNSHARE) and watch dup(0) ending up with descriptor #128, despite #64 being observably not open.

The minimally invasive fix would be to deal with that in dup_fd(). If this proves to add measurable overhead, we can go that way, but let's try to fix copy_fd_bitmaps() first.

* new helper: bitmap_copy_and_expand(to, from, bits_to_copy, size). * make copy_fd_bitmaps() take the bitmap size in words, rather than bits; it's 'count' argument is always a multiple of BITS_PER_LONG, so we are not losing any information, and that way we can use the same helper for all three bitmaps - compiler will see that count is a multiple of BITS_PER_LONG for the large ones, so it'll generate plain memcpy()+memset().

Reproducer added to tools/testing/selftests/core/close_range_test.c

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

mm/hugetlb: fix hugetlb vs. core-mm PT locking

We recently made GUP's common page table walking code to also walk hugetlb VMAs without most hugetlb special-casing, preparing for the future of having less hugetlb-specific page table walking code in the codebase. Turns out that we missed one page table locking detail: page table locking for hugetlb folios that are not mapped using a single PMD/PUD.

Assume we have hugetlb folio that spans multiple PTEs (e.g., 64 KiB hugetlb folios on arm64 with 4 KiB base page size). GUP, as it walks the page tables, will perform a pte_offset_map_lock() to grab the PTE table lock.

However, hugetlb that concurrently modifies these page tables would actually grab the mm->page_table_lock: with USE_SPLIT_PTE_PTLOCKS, the locks would differ. Something similar can happen right now with hugetlb folios that span multiple PMDs when USE_SPLIT_PMD_PTLOCKS.

This issue can be reproduced [1], for example triggering:

[ 3105.936100] ------------[ cut here ]------------ [ 3105.939323] WARNING: CPU: 31 PID: 2732 at mm/gup.c:142 try_grab_folio+0x11c/0x188 [ 3105.944634] Modules linked in: [...] [ 3105.974841] CPU: 31 PID: 2732 Comm: reproducer Not tainted 6.10.0-64.eln141.aarch64 #1 [ 3105.980406] Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20240524-4.fc40 05/24/2024 [ 3105.986185] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 3105.991108] pc : try_grab_folio+0x11c/0x188 [ 3105.994013] lr : follow_page_pte+0xd8/0x430 [ 3105.996986] sp : ffff80008eafb8f0 [ 3105.999346] x29: ffff80008eafb900 x28: ffffffe8d481f380 x27: 00f80001207cff43 [ 3106.004414] x26: 0000000000000001 x25: 0000000000000000 x24: ffff80008eafba48 [ 3106.009520] x23: 0000ffff9372f000 x22: ffff7a54459e2000 x21: ffff7a546c1aa978 [ 3106.014529] x20: ffffffe8d481f3c0 x19: 0000000000610041 x18: 0000000000000001 [ 3106.019506] x17: 0000000000000001 x16: ffffffffffffffff x15: 0000000000000000 [ 3106.024494] x14: ffffb85477fdfe08 x13: 0000ffff9372ffff x12: 0000000000000000 [ 3106.029469] x11: 1fffef4a88a96be1 x10: ffff7a54454b5f0c x9 : ffffb854771b12f0 [ 3106.034324] x8 : 0008000000000000 x7 : ffff7a546c1aa980 x6 : 0008000000000080 [ 3106.038902] x5 : 00000000001207cf x4 : 0000ffff9372f000 x3 : ffffffe8d481f000 [ 3106.043420] x2 : 0000000000610041 x1 : 0000000000000001 x0 : 0000000000000000 [ 3106.047957] Call trace: [ 3106.049522] try_grab_folio+0x11c/0x188 [ 3106.051996] follow_pmd_mask.constprop.0.isra.0+0x150/0x2e0 [ 3106.055527] follow_page_mask+0x1a0/0x2b8 [ 3106.058118] __get_user_pages+0xf0/0x348 [ 3106.060647] faultin_page_range+0xb0/0x360 [ 3106.063651] do_madvise+0x340/0x598

Let's make huge_pte_lockptr() effectively use the same PT locks as any core-mm page table walker would. Add ptep_lockptr() to obtain the PTE page table lock using a pte pointer -- unfortunately we cannot convert pte_lockptr() because virt_to_page() doesn't work with kmap'ed page tables we can have with CONFIG_HIGHPTE.

Handle CONFIG_PGTABLE_LEVELS correctly by checking in reverse order, such that when e.g., CONFIG_PGTABLE_LEVELS==2 with PGDIR_SIZE==P4D_SIZE==PUD_SIZE==PMD_SIZE will work as expected. Document why that works.

There is one ugly case: powerpc 8xx, whereby we have an 8 MiB hugetlb folio being mapped using two PTE page tables. While hugetlb wants to take the PMD table lock, core-mm would grab the PTE table lock of one of both PTE page tables. In such corner cases, we have to make sure that both locks match, which is (fortunately!) currently guaranteed for 8xx as it does not support SMP and consequently doesn't use split PT locks.

[1] https://lore.kernel.org/all/1bbfcc7f-f222-45a5-ac44-c5a1381c596d@redhat.com/

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

md/raid1: Fix data corruption for degraded array with slow disk

read_balance() will avoid reading from slow disks as much as possible, however, if valid data only lands in slow disks, and a new normal disk is still in recovery, unrecovered data can be read:

raid1_read_request
read_balance
raid1_should_read_first
-> return false
choose_best_rdev
-> normal disk is not recovered, return -1
choose_bb_rdev
-> missing the checking of recovery, return the normal disk
-> read unrecovered data

Root cause is that the checking of recovery is missing in choose_bb_rdev(). Hence add such checking to fix the problem.

Also fix similar problem in choose_slow_rdev().

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

mm/vmalloc: fix page mapping if vm_area_alloc_pages() with high order fallback to order 0

The __vmap_pages_range_noflush() assumes its argument pages** contains pages with the same page shift. However, since commit e9c3cda4d86e ("mm, vmalloc: fix high order __GFP_NOFAIL allocations"), if gfp_flags includes __GFP_NOFAIL with high order in vm_area_alloc_pages() and page allocation failed for high order, the pages** may contain two different page shifts (high order and order-0). This could lead __vmap_pages_range_noflush() to perform incorrect mappings, potentially resulting in memory corruption.

Users might encounter this as follows (vmap_allow_huge = true, 2M is for PMD_SIZE):

kvmalloc(2M, __GFP_NOFAIL|GFP_X)
__vmalloc_node_range_noprof(vm_flags=VM_ALLOW_HUGE_VMAP)
vm_area_alloc_pages(order=9) ---> order-9 allocation failed and fallback to order-0
vmap_pages_range()
vmap_pages_range_noflush()
__vmap_pages_range_noflush(page_shift = 21) ----> wrong mapping happens

We can remove the fallback code because if a high-order allocation fails, __vmalloc_node_range_noprof() will retry with order-0. Therefore, it is unnecessary to fallback to order-0 here. Therefore, fix this by removing the fallback code.