mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-09-22 09:34:56 +02:00
aedf2efd18977e0cef7eb963166e2b1fcc0aa321
1463866
Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
 Hyunwoo Kim
|
aedf2efd18 |
mm/pagewalk: fix stale walk->action escaping walk_pmd_range()
If ->pmd_entry() sets walk->action = ACTION_AGAIN, the pmd_none() check is retried. The PMD entry may be cleared at the point of retry. In this case, if walk->ops->install_pte is not specified, the code continues to the next PMD entry in the range without resetting walk->action to ACTION_SUBTREE. This leaves walk->action erroneously set to ACTION_AGAIN, which is incorrect. This was incorrect but not problematic up until commit |
||
 Youngjun Park
|
10d9012e83 |
mm, swap: don't free a hibernation slot that is in the swap cache
A slot with a folio in the swap cache is freed when the folio leaves the
cache, not when its count drops. swap_put_entries_cluster() follows that
rule. swap_free_hibernation_slot() does not, it calls
__swap_cluster_free_entries() whether or not a folio sits on the slot.
Cluster readahead can put one there. It walks a raw page_cluster sized
window of offsets around the faulting entry, and a hibernation slot passes
__swap_cache_add_check() because it is not a folio and its count is not
zero. Freeing the slot then clears the entry under that folio.
The folio is now unreachable from the swap table, and the offset goes back
to the allocator. The folio is still on the LRU though, so reclaim can
pick it up later. It then takes the old offset out of folio->swap and
overwrites the table entry there, which by then may belong to someone
else.
This bug can trigger silent memory corruption, process crashes, or data
instability across completely unrelated userspace applications - typically
occurring when uswsusp is preparing the hibernation image.
I found this while working on giving hibernation slots their own marker in
the swap table, which I had discussed with Kairui.
(https://lore.kernel.org/linux-mm/abp7aDgYLrxF3Me8@KASONG-MC4/) As far as
I know there are no reports, so there is no Reported-by/Closes to add.
Check for a cached folio before freeing. The slot is then left in the
ordinary state where only the swap cache holds it, and it is freed when
the folio leaves the cache, either through the reclaim below or through
normal reclaim later.
Link: https://lore.kernel.org/20260811132209.2862708-2-youngjun.park@lge.com
Fixes:
|
||
 Guopeng Zhang
|
92192e9c5e |
mm: memcg-v1: fix memsw and TCP failcnt accounting
Commit |
||
 Breno Leitao
|
25f52e8121 |
mm/vmscan: report RCU-tasks quiescent states in shrink_lruvec()
I am seeing some rcu_tasks stalls in the Meta fleet during reclaim. INFO: rcu_tasks detected stalls on tasks: 0000000088620d09: .. nvcsw: 6735/6735 holdout: 1 idle_cpu: -1/8 task:GlobalCPUThread state:R running task pid:2552016 tgid:2524552 Call Trace: shrink_lruvec mem_cgroup_iter shrink_node do_try_to_free_pages try_to_free_pages __alloc_frozen_pages_noprof alloc_pages_noprof pte_alloc_one __pte_alloc handle_mm_fault Nothing promises direct reclaim returns in bounded time, and the scan loop in shrink_lruvec() only calls cond_resched(), which is a no-op on PREEMPTION kernels. Involuntary preemption is not a Tasks-RCU quiescent state, so the reclaiming task never reports one and becomes a holdout. Upgrade it to cond_resched_tasks_rcu_qs(), which reports a quiescent state even when cond_resched() does nothing. PS: This has been discussed in [1] Link: https://lore.kernel.org/20260810-rcu_task_shrink_lruvec-v1-1-4d9f7d5251cb@debian.org Link: https://lore.kernel.org/all/amdWVTs0WKOxguxP@gmail.com/ [1] Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Kairui Song <kasong@tencent.com> Cc: Lorenzo Stoakes <ljs@kernel.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
 Guodong Xu
|
2100f04bc6 |
mailmap: add entries for Guodong Xu
Map my old Linaro and RISCstar email addresses to my current personal address. Neither former address receives mail anymore. Link: https://lore.kernel.org/20260807-b4-mailmap-guodong-xu-v2-1-f7c71bc6bd9f@gmail.com Signed-off-by: Guodong Xu <docular.xu@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
 JP Kobryn
|
bd24ce159b |
MAINTAINERS, mailmap: update email address for JP Kobryn
Switch to my linux.dev address and add previous one to mailmap. Link: https://lore.kernel.org/20260807010226.8995-1-jp.kobryn@linux.dev Signed-off-by: JP Kobryn <jp.kobryn@linux.dev> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
 Phillip Lougher
|
3366ddf30e |
MAINTAINERS: remove git URL for Squashfs
The squashfs-next.git URL hasn't been updated for many years, and it now doesn't exist. So remove it from the MAINTAINERS entry. Link: https://lore.kernel.org/20260806181916.617881-1-phillip@squashfs.org.uk Signed-off-by: Phillip Lougher <phillip@squashfs.org.uk> Cc: Derek Barbosa <debarbos@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
 Shakeel Butt
|
bf4ade7dbd |
memcg: keep folio's objcg same as its node
memcg_reparent_objcgs() has an inherent assumption that a folio's objcg is
the objcg of the folio's node. Folio migration across nodes breaks that
assumption: the new folio simply inherits the old folio's objcg while
living on a different node.
Once the assumption is broken, the reparenting of the folio's objcg and
the reparenting of the folio's LRU list are no longer atomic.
memcg_reparent_objcgs() handles one node per iteration and drops all the
locks in between, so the objcg gets reparented in the iteration for the
objcg's node while the LRU list gets spliced in the iteration for the
folio's node. Any LRU operation on that folio in between resolves its
lruvec through the objcg, and thus takes the lru_lock of the wrong memcg,
not the lru_lock of the list the folio is actually on.
Fix this by selecting the objcg by folio_nid() at charge time, and by
re-deriving it for the destination node in mem_cgroup_migrate() and
mem_cgroup_replace_folio().
Link: https://lore.kernel.org/20260807142406.443516-1-shakeel.butt@linux.dev
Fixes:
|
||
 SJ Park
|
1ec0e6b6f7 |
mm/damon: adjust isolated pages stat for DAMOS_MIGRATE_{HOT,COLD}
Callers of migrate_pages() should adjust NR_MIGRATED_{ANON,FILE} for
isolations and putback of the folios. That for migration succeeded folios
is done by migrate_pages(), in migrate_folio_done(). That for MR_DEMOTION
reason is an exception though.
DAMOS_MIGRATE_{HOT,COLD} call migrate_pages() but mistakenly not doing the
stat adjustment. As a result, use of DAMOS_MIGRATE_{HOT,COLD} could
corrupt the stat. It could confuse too_many_isolated(), make compaction
and reclaim to behave in unexpected ways. The stat corruption can be
reproduced and confirmed using DAMON user-space tool [1] on NUMA systems,
like below.
$ numactl --hardware
available: 2 nodes (0-1)
[...]
$ sudo ./damo start --damos_action migrate_hot 1
$ sudo cat /proc/sys/vm/stat_refresh
$ sudo dmesg
[...]
[ 80.215554] vmstat_refresh: nr_isolated_anon -5578
[ 80.216842] vmstat_refresh: nr_isolated_file -34400
This issue was discovered [2] by Sashiko.
Link: https://lore.kernel.org/20260728140404.94476-1-sj@kernel.org
Link: https://github.com/damonitor/damo [1]
Link: https://lore.kernel.org/20260726164356.87940-1-sj@kernel.org [2]
Fixes:
|
||
 liyouhong
|
5deb65c34e |
mm/damon/ops-common: putback folios on invalid migrate nid
damon_pa_migrate() and damos_va_migrate() isolate folios into a local list
and then call damon_migrate_pages(). When target_nid is invalid
(including the scheme default NUMA_NO_NODE / -1), damon_migrate_pages()
returns early without putting the folios back to the LRU.
Callers then discard the list head while those folios remain isolated with
an extra reference taken by folio_isolate_lru(). The pages stay off the
LRU for as long as the mapping exists (anon active+inactive counts drop
while RSS does not), and the leftover references can pin the pages after
the mapping is gone.
Put the folios back on the invalid-nid path so ignored migration requests
still return them to the LRU.
Link: https://lore.kernel.org/20260726014815.1280757-1-dayou5941@163.com
Fixes:
|
||
 Matt Fleming
|
aca1f2d5de |
mm/huge_memory: initialise workingset state before folio split
xas_try_split() adds __GFP_ACCOUNT for page-cache xa_nodes, but
__folio_split() leaves the xa_state's xa_lru unset. That lets a live,
memcg-charged xa_node exist without being linked into the mapping's
shadow_nodes list_lru; when reclaim later walks the list_lru it trips
VM_WARN_ON(!css_is_dying()).
Use mapping_set_update() to install both the workingset update callback
and the shadow_nodes list_lru on the xa_state.
Link: https://lore.kernel.org/20260725101419.3938406-1-matt@readmodwrite.com
Fixes:
|
||
 Zhiling Zou
|
8db4bab826 |
mm/page_table_check: skip special zero mappings
page_table_check_set() and page_table_check_clear() account mappings based
on PageAnon(). Shared zero-page PTEs and huge zero PMDs are special
mappings, but page_table_check can still account them as file-backed
pages.
An unprivileged process can populate enough zero mappings to overflow
file_map_count and hit the existing BUG_ON(). The PTE path can do this
with the shared zero page, and the PMD path can do the same with huge zero
mappings.
Skip special zero mappings in the user page-table accounting paths. Keep
the PTE-side pte_special() check, and identify huge zero PMDs from the
mapped folio instead of pmd_special(). That covers architectures where
pmd_special() is a no-op without adding huge_zero_pfn checks to the
generic counter helpers.
Link: https://lore.kernel.org/cover.1784717203.git.zhilinz@nebusec.ai
Link: https://lore.kernel.org/e94478e4fb7912fb7e8ebebed5ce85d00dc9a69d.1784717203.git.zhilinz@nebusec.ai
Fixes:
|
||
|
SJ Park
|
0f18683103 |
mm/damon/lru_sort: skip damon_call() if ctx has not started
DAMON_LRU_SORT calls damon_call() for commit_inputs parameter user input
if the DAMON context is initialized. The context could be initialized,
but not yet successfully started. In the case, damon_call() could
indefinitely hang. Read the comment on damon_call() for more detail. Fix
the problem by memorizing if the DAMON context has ever successfully
started, and skip damon_call() if it has not.
This issue can easily be reproduced by writing Y to the commit_inputs
parameter file on a system that DAMON_LRU_SORT has not turned on before.
Link: https://lore.kernel.org/20260803134646.16640-3-sj@kernel.org
Fixes:
|
||
|
SJ Park
|
b9b6bad94c |
mm/damon/reclaim: skip damon_call() if ctx has not started
Patch series "mm/damon/{reclaim,lru_sort}: fix commit_inputs infinite
hang".
Writing 'Y' to commit_inputs parameters of DAMON_RECLAIM and
DAMON_LRU_SORT before the modules were ever turned on causes infinite
hang. Fix those.
The issue was discovered [1] by Sashiko.
This patch (of 2):
DAMON_RECLAIM calls damon_call() for commit_inputs parameter user input if
the DAMON context is initialized. The context could be initialized, but
not yet successfully started. In the case, damon_call() could
indefinitely hang. Read the comment on damon_call() for more detail. Fix
the problem by memorizing if the DAMON context has ever successfully
started, and skip damon_call() if it has not.
This issue can easily be reproduced by writing Y to commit_inputs on a
system that DAMON_RECLAIM was not turned on before.
Link: https://lore.kernel.org/20260803134646.16640-1-sj@kernel.org
Link: https://lore.kernel.org/20260803134646.16640-2-sj@kernel.org
Link: https://lore.kernel.org/20260802173021.762-1-sj@kernel.org [1]
Fixes:
|
||
|
SJ Park
|
06befa61c4 |
mm/damon/lru_sort: error out for >10000 active_mem_bp
damos_quota_score() can trigger division by zero if the target value is
zero. DAMON_LRU_SORT lets users set the target value for the hot memory
scheme via active_mem_bp parameter. It avoids setting it as the target
value if the parameter value is zero. However, it also sets the cold
memory scheme with a target value that is calculated as '10000 -
active_mem_bp + 2'. Hence, if a user sets active_mem_bp 10002, the cold
memory scheme's quota goal target value can be zero. As a result,
division by zero can be triggered. Fix by returning an error when the
user tries to start DAMON with >10000 active_mem_bp parameter value.
It makes no sense to set active_mem_bp with 10002. It also requires
module parameters write permission to reproduce the issue. That said, the
consequence is quite bad.
One reliable way to reproduce the issue is like below:
# cd /sys/module/damon_lru_sort/parameters
# echo 1000 > wmarks_high
# echo 995 > wmarks_mid
# echo 0 > wmarks_low
# echo 10002 > active_mem_bp
# echo Y > enabled
# dmesg -w
[...]
[ 597.421247] Oops: divide error: 0000 [#1] SMP NOPTI
[ 597.428848] RIP: 0010:damos_quota_score+0x6f/0x480
This issue was discovered [1] by Sashiko.
Link: https://lore.kernel.org/20260803134034.15217-3-sj@kernel.org
Link: https://lore.kernel.org/20260801213028.5127-1-sj@kernel.org [1]
Fixes:
|
||
|
SJ Park
|
a16fd3ad9d |
samples/damon/mtier: error out for zero quota goal target values
Patch series "mm/damon: avoid division by zero from damos_quota_score()".
DAMON_SAMPLE_MTIER and DAMON_LRU_SORT allow the user to trigger division
by zero in damos_quota_score(). Avoid it by adding parameters validation
checks.
This patch (of 2):
damos_quota_score() can trigger division by zero if the target_value is
zero. DAMON_SAMPLE_MTIER lets users set the target_value via
node0_mem_{used,free}_bp parameters. It doesn't guard zero value case,
though. As a result, users can trigger division by zero. Fix the issue
by returning an error when the user tries to start DAMON with zero
node0_mem_{used,free}_bp parameter values.
DAMON_SAMPLE_MTIER is just a sample module, but the consequence is quite
bad. Also the zero node0_mem_free_bp parameter might look like a
reasonable setup to some users. Hence, the issue might really happen in
the real world.
One reliable way to reproduce the issue is like below:
# cd /sys/module/damon_sample_mtier/parameters
# echo 4096 > node0_start_addr
# echo 8192 > node0_end_addr
# echo 8192 > node1_start_addr
# echo 81920 > node1_end_addr
# echo 0 > node0_mem_free_bp
# echo Y > enabled
# dmesg -w
[...]
[18792.235916] Oops: divide error: 0000 [#1] SMP NOPTI
[...]
[18792.242787] RIP: 0010:damos_quota_score+0x6f/0x480
[...]
This issue was discovered [1] by Sashiko.
Link: https://lore.kernel.org/20260803134034.15217-1-sj@kernel.org
Link: https://lore.kernel.org/20260803134034.15217-2-sj@kernel.org
Link: https://lore.kernel.org/20260801202657.117135-1-sj@kernel.org [1]
Fixes:
|
||
 Danila Tikhonov
|
4194140a51 |
mailmap: map old addresses to Danila Tikhonov
Map my old jiaxyga.com and ProtonMail addresses to the current mainlining.org address. Link: https://lore.kernel.org/20260801153333.296218-1-danila@mainlining.org Signed-off-by: Danila Tikhonov <danila@mainlining.org> Cc: Jakub Kacinski <kuba@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
 Lorenzo Stoakes (ARM)
|
98bd3af0bb |
mm/huge_memory: separate out CONFIG_PERSISTENT_HUGE_ZERO_FOLIO logic
Rather than mixing the refcounted and non-refcounted
CONFIG_PERSISTENT_HUGE_ZERO_FOLIO logic, separate the two out cleanly so
it is clear what happens when this configuration option is set and what
happens when it is not.
Introduce HUGE_ZERO_UNSET_PFN to abstract the ~0UL assignment, only
introduce the refcount, lock and shrinker if
!CONFIG_PERSISTENT_HUGE_ZERO_FOLIO, abstract initialisation and teardown,
abstract the huge zero folio allocation from refcounting.
Also change a BUG_ON() to WARN_ON_ONCE() while we're at it.
No functional change intended.
Link: https://lore.kernel.org/20260730-fix-refcounted-huge-zero-v2-2-c5d8a41b317f@kernel.org
Signed-off-by: Lorenzo Stoakes (ARM) <ljs@kernel.org>
Fixes:
|
||
|
Lorenzo Stoakes (ARM)
|
33192a26cd |
mm/huge_memory: fix huge_zero_pfn race
Patch series "mm/huge_memory: fix huge_zero_pfn race", v2.
There is a subtle race in the reference-counted huge_zero_folio
implementation.
The fast path atomic logic fails to account for the fact that the shrinker
(which drops the final huge_zero_refcount pin) can overwrite huge_zero_pfn
with the ~0UL sentinel value in shrink_huge_zero_folio_scan() after a
racing get_huge_zero_folio() installed a valid value there.
This results in huge_zero_folio being correctly set but huge_zero_pfn
being set incorrectly and thus is_huge_zero_pfn() and consequently
is_huge_zero_pmd() will misidentify the huge zero folio as being an
ordinary THP folio.
This can result in the huge zero folio being split and otherwise treated
incorrectly.
The solution to this is very subtle as there is an atomic fast path, and
thus ordering in weakly ordered architectures has to be treated very
carefully.
The first commit fixes the issue by introducing a spinlock around
huge_zero_[pfn, folio, refcount] write, with careful consideration paid to
load/store ordering in the fast path. It is placed first and kept as
small as possible so that it can be backported on its own.
The second commit is a pure cleanup which reworks the
CONFIG_PERSISTENT_HUGE_ZERO_FOLIO logic to better separate the persistent
logic from the dynamically allocated one.
This patch (of 2):
If !CONFIG_PERSISTENT_HUGE_ZERO_FOLIO, the huge_zero_folio is refcounted
by huge_zero_refcount and returned by mm_get_huge_zero_folio().
When the caller is done with the huge zero page, its reference count is
decremented. Only a shrinker can set the reference count to zero.
A race can unfortunately occur between a shrinker decrementing the
reference count to zero and a concurrent page fault.
This is because shrink_huge_zero_folio_scan() might, if very unlucky, be
preempted between setting huge_zero_refcount to zero and writing an
invalid value.
During this time get_huge_zero_folio() could write to huge_zero_pfn before
shrink_huge_zero_folio_scan() resumes.
In this event the huge zero folio will be persistently misidentified
causing the THP code path to be entered inappropriately for the huge zero
folio:
CPU 0 CPU 1
=======================================|=================================
shrink_huge_zero_folio_scan() |
atomic_cmpxchg() sets refcount to 0 |
xchg() sets huge_zero_folio to NULL | get_huge_zero_folio()
| | atomic_inc_not_zero() -> zero
preempted for a long time | Allocate new huge zero folio
| | Write valid huge_zero_folio
v | Write valid huge_zero_pfn
Overwrite huge_zero_pfn with ~0UL <--- Invalid overwrite!
This results in is_huge_zero_pfn() and is_huge_zero_pmd() incorrectly
returning false for a huge zero page which could result in issues like the
huge zero folio being incorrectly split.
Note that the issue is with huge_zero_pfn not huge_zero_folio, as
get_huge_zero_folio() uses cmpxchg() gated on huge_zero_folio being NULL
with a retry loop and shrink_huge_zero_folio_scan() uses xchg() to set
huge_zero_folio.
Fix the issue by introducing a spinlock, huge_zero_lock, to prevent
concurrent write of huge_zero_folio, huge_zero_pfn and huge_zero_refcount.
There needs to be significant care taken here to ensure correctness:
The fast path in get_huge_zero_folio() uses atomic_inc_not_zero(), which
is outside of the critical section, and means huge zero allocation is
gated on zero huge_zero_refcount.
The fast path doesn't use huge_zero_lock, so the critical section is
irrelevant to it.
So invariants are required - huge_zero_refcount MUST:
* Only be set in the huge_zero_lock critical section to ensure
serialisation of huge_zero_pfn, huge_zero_folio and huge_zero_refcount
writes.
* Be set non-zero only AFTER huge_zero_[pfn, folio] are set to valid values
so installation of the huge zero folio on read page fault ensures
concurrent is_huge_zero_*() calls correctly identify the huge zero folio.
* Be set zero only BEFORE huge_zero_[pfn, folio] are set to NULL and ~0UL
respectively, and atomically.
Establish these by:
* Only setting huge_zero_refcount to zero or an absolute value in the
huge_zero_lock critical section in get_huge_zero_folio() and
shrink_huge_zero_folio_scan(), and always updating atomically there
and elsewhere.
* Using atomic_set_release(&huge_zero_refcount) in get_huge_zero_folio()
after huge_zero_[pfn, folio] are set. This is paired with
atomic_inc_not_zero() to ensure atomic_inc_not_zero() only observes a
non-zero value if huge_zero_[pfn, folio] are set.
* Using atomic_cmpxchg() in shrink_huge_zero_folio_scan() (as before) to
ensure that it is set zero only when equal to 1 and set atomically.
* atomic_cmpxchg() being fully ordered ensures this is done prior to
huge_zero_[folio, pfn] being set to NULL and ~0UL respectively.
Eliminate the retry loop in get_huge_zero_folio() as the atomic_cmpxchg()
in shrink_huge_zero_folio_scan() is now performed under the lock, and
replace with an equally locked atomic_inc() to set the reference count
should the caller be raced on huge zero folio installation.
folio_put() naturally implies a full memory barrier so its ordering is
maintained correctly.
The huge zero folio also cannot be released except when the shrinker does
so as it is non-LRU and non-rmappable.
Note that only the huge zero shrinker (via shrink_huge_zero_folio_scan())
can actually set huge_zero_refcount to zero, which is the count of mm's
which have at least one huge zero folio installed plus one shrinker pin.
Additionally convert a BUG_ON() to a VM_WARN_ON_ONCE().
Link: https://lore.kernel.org/20260730-fix-refcounted-huge-zero-v2-0-c5d8a41b317f@kernel.org
Link: https://lore.kernel.org/20260730-fix-refcounted-huge-zero-v2-1-c5d8a41b317f@kernel.org
Fixes:
|
||
 Brendan Jackman
|
50124648db |
MAINTAINERS: update address for Brendan Jackman
Switch my entry in MAINTAINERS and .mailmap to my @linux.dev email address Link: https://lore.kernel.org/20260729-email-change-v1-1-666ae7c2b7fc@google.com Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Brendan Jackman <brendan.jackman@linux.dev> Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: Lorenzo Stoakes (ARM) <ljs@kernel.org> Acked-by: Zi Yan <ziy@nvidia.com> Cc: David Hildenbrand <david@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Liam R. Howlett <liam@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
 Hugh Dickins
|
86da3f7e1e |
mm/filemap: __filemap_add_folio() restore index before retrying
In __filemap_add_folio()'s split-a-conflict loop, xas_set_order() is
applied repeatedly: each application modifies xas.xa_index, rounding it
down according to the split_order attempted at that stage: and if all goes
as intended, it eventually (or immediately) converges on an
xas_try_split() to the required folio_order, with xas.xa_index now the
same as index: then xas_store() puts the new folio into the xarray there.
But if a new node was needed, and GFP_NOWAIT allocation did not get one,
the lock is dropped, xas_nomem() used to allocate, and sequence retried.
If (that part of) the xarray is unchanged when the lock is reacquired, no
problem. But what if the conflict was meanwhile resolved by another
thread (perhaps even doing the same thing, inserting a folio at that same
index)? Isn't there a danger of now putting our folio into the xarray at
an intermediate rounded-down index? With !folio_contains() bug to follow,
when CONFIG_DEBUG_VM=y is checking for that.
Fix this with an xas_set_order() to restore the original xas.xa_index at
the bottom of the loop, so the retry does a full re-evaluation after
reacquiring the lock, and cannot reach xas_store() with the wrong index.
Production was suffering from rare SIGILLs and SIGSEGVs, executable text
found a page away from where it belonged, !folio_contains() bug hit when
debug enabled: symptoms not seen since this patch went in.
Link: https://lore.kernel.org/562fbfa6-dd6d-0b6a-2461-ed2ff1173bc8@google.com
Fixes:
|
||
 Ramin Moussavi
|
c2689266e5 |
microblaze: restore the page alignment of swapper_pg_dir
microblaze handles TLB misses in software, and the handler builds the address of the L1 entry by ORing the index into the page directory base instead of adding it (hw_exception_handler.S): bsrli r5, r3, PGDIR_SHIFT - 2 andi r5, r5, PAGE_SIZE - 4 /* Assume pgdir aligned on 4K boundary, no need for "andi r4,r4,0xfffff003" */ or r4, r4, r5 lwi r4, r4, 0 /* Get L1 entry */ The index is masked to the low 12 bits, so the OR only works if those bits of the base are zero -- which is exactly the assumption the comment states and the reason the masking of the base can be skipped. swapper_pg_dir had no alignment directive of its own. It was aligned because it followed empty_zero_page in head.S, and that one carried the .align 12: .section .data .global empty_zero_page .align 12 empty_zero_page: .space PAGE_SIZE .global swapper_pg_dir swapper_pg_dir: .space PAGE_SIZE Commit |
||
|
Lorenzo Stoakes (ARM)
|
9d3277b2c0 |
arm64: remove redundant concurrent ptdump UAF mitigation
This partially reverts commit |
||
|
Lorenzo Stoakes (ARM)
|
27c32e5538 |
mm/ptdump: always stabilise against page table freeing using init_mm
Previous commits have established the invariant that kernel page table freeing is performed while an mmap read lock on init_mm is held, which fixes races between ptdump and kernel page table freeing over init_mm. However, x86 and arm64 can perform a ptdump over an mm other than init_mm via ptdump_walk_pgd() and since kernel memory ranges are shared across non-kernel mm's, this means that the race still exists for these cases. Fix this by acquiring a nested mmap write lock for init_mm in ptdump_walk_pgd(). This is safe as we take this after mmap write locking the mm, and nothing acquires the init_mm lock first before locking an arbitrary mm, so no deadlock is possible. Also update walk_page_range_debug() to assert that init_mm is write locked, add a comment explaining why and remove some redundant code, and eliminate the unnecessary and confusing invocation of walk_kernel_page_table_range(). We can safely remove the non-NULL check for walk.mm, as the mmap lock asserts would NULL pointer deref if it was (and of course no callers do this). The first point at which ptdump can race kernel page table freeing is commit |
||
|
Lorenzo Stoakes (ARM)
|
26444eb714 |
mm/vmalloc: acquire init_mm lock on huge vmap to avoid ptdump UAF
Patch series "mm: fix UAF caused by race between ptdump and vmap pgtable freeing", v6. Kernel page table walkers fall into two broad categories - those ranges where no exclusion is required via walk_kernel_page_table_range_lockless() and those where exclusion is required via walk_kernel_page_table_range() or walk_page_range_debug(). The former category is used only by arm64 arch code operating on ranges it both wholly owns and does not concurrently write. The latter category consists of kernel page table walkers operating on ranges that are wholly owned (but which need exclusion against concurrent writers). The lock used for exclusion is the mmap lock, and for kernel ranges this is the mmap lock on init_mm. ptdump is a special case being both the only user of walk_page_range_debug(), and the only case in which it walks ranges it does not own. This presents a problem, as page tables may be freed under ptdump. And indeed there is a use-after-free bug in the kernel as a result, which this series addresses. vmap promotes page tables to huge leaf entries where possible, freeing the lower page table when it does. It does this with no meaningful locks held against concurrent ptdump walks. As a result, use-after-free can currently occur. This series addresses the issue by having the vmap huge promotion logic acquire the mmap read lock while both setting the huge page table entry and freeing the prior leaf page table. The ptdump code already acquires the mmap write lock, so by doing so we ensure that the ptdump walker only ever observes either the huge page table entry or the existing page table entry, and nothing is freed underneath it. A mitigation for this issue was already applied for arm64 in commit |
||
 Chris Gellermann
|
9f1d75a4ce |
selftests/mm: fix potential wild pointer access of getline due to missing init
This is another occurrence of using getline where the code assumes that
getline allocates memory to store the line, but the pointer passed to it
is uninitialized and potentially a non-null pointer. This violates the
Open Group Spec[1] and caused a segfault in a similar situation in
selftest/clone3/clone3_set_tid. Fix it by initializing the line pointer
to NULL.
The issue has been found by simply grepping through the selftest code
after running into the issue in clone3_set_tid. Whether it segfaults in
its current state is unknown to me. But it's good to be addressed due to
defensive reasons.
Link: https://lore.kernel.org/20260722130246.2135563-3-christian.gellermann@codasip.com
Link: https://pubs.opengroup.org/onlinepubs/9799919799/functions/getline.html [1]
Fixes:
|
||
|
Chris Gellermann
|
8f6f9fd93c |
selftests/clone3: fix wild pointer access of getline due to missing init
Patch series "selftests: Add missing initalization of pointer passed to
getline", v2.
This patch (of 2):
Clone3_set_tid uses getline(&line, ...) in a loop to read the child's
process status. The code expects that getline allocates the buffer for
the line on the first loop iteration. According to the Open Group
Spec[1], char *line has to be null pointer for this:
> ssize_t getline(char **restrict lineptr, ...);
> If *lineptr is a null pointer or if the object pointed to by *lineptr
> is of insufficient size, an object shall be allocated as if by
malloc()
> or the object shall be reallocated as if by realloc()[...].
However, char *line is only declared, leading to an undefined value that
is potentially non-null. In an example run with Musl v1.2.6, the realloc
call[2] of getdelim, which implements getline, triggers a segfault:
./run_kselftest.sh --test clone3:clone3_set_tid
[ 1366.165898] kselftest: Running tests in clone3
...
[ 1367.799244] clone3_set_tid[811]: unhandled signal 11 code 0x1 at
0x0000000000000000 in libc.so[68184,3fbf69f000+4c000]
[ 1367.802808] CPU: 0 UID: 0 PID: 811 Comm: clone3_set_tid Not tainted
..
[ 1367.804188] epc: 0x0000003fbf6b0184
[ 1367.804188] ra : 0x0000003fbf6d4664
[ 1367.804188] sp : 0x0000003fce5f2e40
[ 1367.805314] gp : 0x0000002aaab0dfb8
[ 1367.805314] tp : 0x0000003fbf6f14a8
[ 1367.805314] t0 : 0x0000003fbf63d000
...
Looking at the realloc implementation, Musl mallocs for a null pointer
memory. But for a non-null pointer, it assumes it's passed a valid
pointer to the heap and tries to access its meta-data. This leads to the
segfault we see:
void *realloc(void *p, size_t n)
{
if (!p) return malloc(n);
if (size_overflows(n)) return 0;
struct meta *g = get_meta(p);
...
}
Fix this by properly initializing the line pointer to NULL.
Link: https://lore.kernel.org/20260722130246.2135563-1-christian.gellermann@codasip.com
Link: https://lore.kernel.org/20260722130246.2135563-2-christian.gellermann@codasip.com
Link: https://pubs.opengroup.org/onlinepubs/9799919799/functions/getline.html [1]
Link: https://git.musl-libc.org/cgit/musl/tree/src/stdio/getdelim.c#n38 [2]
Fixes:
|
||
 Link Lin
|
0b45f6927a |
mm/page_reporting: use system_freezable_wq to fix UAF during suspend
During PM freeze (e.g. S3 suspend or S4 hibernation), device drivers like
virtio_balloon reset their underlying virtio devices and delete their
virtqueues via vdev->config->del_vqs().
However, page reporting work (page_reporting_process) was scheduled on the
global system_wq. Because system_wq lacks the WQ_FREEZABLE flag, the PM
freezer skips it, leaving page_reporting_process active during suspend.
If pages are freed into the buddy allocator while suspending (for example,
when core MM invokes the balloon shrinker during S4 hibernation image
saving), page reporting triggers virtballoon_free_page_report() on deleted
virtqueues, resulting in a Use-After-Free / General Protection Fault:
[ 196.795226] general protection fault, probably for non-canonical address 0xaa1436fe70dae6df: 0000 [#1] SMP NOPTI
[ 196.825967] Workqueue: events page_reporting_process
[ 196.831038] RIP: 0010:virtqueue_add_split+0x233/0x4c0 [virtio_ring]
[ 196.927073] virtballoon_free_page_report+0x3a/0xe0 [virtio_balloon]
[ 196.946943] page_reporting_process+0x370/0x4f0
Fix this by switching page reporting work to system_freezable_wq. This
ensures that the PM freezer pauses page_reporting_process before device
drivers destroy their reporting virtqueues. Because the reporting worker
is frozen, memory reclamation/freeing (e.g. via shrinker execution) can
safely return pages to MM during freeze without triggering unfrozen
reporting work on deleted virtqueues.
This aligns with the driver's existing design. The comment in
virtballoon_freeze() states:
/*
* The workqueue is already frozen by the PM core before this
* function is called.
*/
Testing:
I have verified these fixes using Google’s virtualization infrastructure
by running continuous suspend/resume iterations (40+ cycles) while
churning memory using stress-ng (`stress-ng --vm 4 --vm-bytes 60%
--timeout 1`) to constantly create free pages for the buddy allocator. We
also set the `page_reporting_order` parameter to 0 to make the page
reporting worker highly sensitive, forcing it to pick up any 4K free
pages. This confirmed that the UAF crashes are no longer reproducible.
Link: https://lore.kernel.org/20260721005603.1710551-1-linkl@google.com
Fixes:
|
||
 Richard Chang
|
dc37771a43 |
mm: vmscan: abort proactive reclaim early when freezing for suspend
Proactive reclaim (triggered via memory.reclaim or node sysfs) checks for pending signals in its outer loop in user_proactive_reclaim(). However, the inner reclaim loops—specifically scanning cgroups in shrink_many() and evicting/aging folios in try_to_shrink_lruvec()—can run for a long time before returning to the outer loop, especially on systems with many cgroups or large memory sizes. During system suspend, the PM freezer attempts to freeze all tasks by sending fake signals (setting TIF_SIGPENDING). Because the inner loops do not check for pending signals, the proactive reclaim task can remain stuck in kernel space for seconds, failing to enter the refrigerator in a timely manner. This leads to suspend failures due to freeze timeouts, a behavior observed on Android devices. This latency issue is specific to proactive reclaim because of its large, user-defined reclaim targets (could be gigabytes). Since commit |
||
 Nico Pache (Red Hat)
|
8c7372c5b1 |
MAINTAINERS: update Nico Pache's email address
Switch my entry in MAINTAINERS and .mailmap to my @linux.dev email address Link: https://lore.kernel.org/20260721101811.115954-1-nico.pache@linux.dev Signed-off-by: Nico Pache <npache@redhat.com> Signed-off-by: Nico Pache (Red Hat) <nico.pache@linux.dev> Acked-by: David Hildenbrand (Arm) <david@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
 Peter Collingbourne
|
1fcac73551 |
arm64, mailmap: update email address for Peter Collingbourne
I am no longer at Google. Link: https://lore.kernel.org/20260718172923.8297-1-peter@pcc.me.uk Signed-off-by: Peter Collingbourne <peter@pcc.me.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Ian Rogers <irogers@google.com> Cc: Jakub Kacinski <kuba@kernel.org> Cc: Martin Kepplinger <martink@posteo.de> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
 Burak Emir
|
598356522b |
MAINTAINERS: update address for Burak Emir
Update MAINTAINERS and .mailmap to point to my gmail.com address: burak.emir@gmail.com. Link: https://lore.kernel.org/20260718151303.2649-1-burak.emir@gmail.com Signed-off-by: Burak Emir <burak.emir@gmail.com> Cc: Alice Ryhl <aliceryhl@google.com> Cc: Jakub Kacinski <kuba@kernel.org> Cc: Martin Kepplinger <martink@posteo.de> Cc: Yury Norov (NVIDIA) <yury.norov@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
 Kiryl Shutsemau (Meta)
|
e923bd2105 |
mm/huge_memory: unlock i_mmap_rwsem before releasing after-split folios
__folio_split() keeps dereferencing the mapping after the split:
shmem_uncharge(mapping->host) and remap_page() while the folios are still
frozen/locked, and i_mmap_unlock_read(mapping) at the very end, after the
after-split folios have been unlocked and freed.
Nothing holds an inode reference across that. The split relies on @folio
-- which the beyond-EOF drop loop never removes, as it starts at
folio_next(folio) -- staying locked and in the page cache to hold off
eviction. But the unlock loop unlocks @folio before i_mmap_unlock_read()
runs. If the caller's @lock_at is a tail beyond EOF, as memory_failure()
passes when splitting a poisoned tail of a shmem THP that reaches past
i_size during truncation, it too is gone from the page cache; so once
@folio is unlocked no locked, in-cache folio pins the inode, and a
concurrent final iput() can evict and RCU-free it before
i_mmap_unlock_read() touches i_mmap_rwsem:
BUG: KASAN: slab-use-after-free in __up_read+0x634/0x790
i_mmap_unlock_read include/linux/fs.h:537 [inline]
__folio_split+0x732/0x1640 mm/huge_memory.c:4100
try_to_split_thp_page+0xab/0x390 mm/memory-failure.c:1675
memory_failure+0x1394/0x26e0 mm/memory-failure.c:2470
Freed by task 4601:
shmem_free_in_core_inode+0x54/0xb0 mm/shmem.c:5177
evict+0x57f/0xac0 fs/inode.c:870
Do every mapping dereference while @folio still pins the inode: drop
i_mmap_rwsem right after remap_page(), before the loop that unlocks and
frees the after-split folios, and clear @mapping so the exit path does not
unlock it again. shmem_uncharge() and remap_page() already run before
that point, so after this nothing past the unlock loop touches the inode
or the mapping.
This is now a rule the split depends on, alongside keeping @folio frozen
until the page cache is updated: no inode or mapping dereference once the
after-split folios start being unlocked.
Link: https://lore.kernel.org/20260716095424.471052-1-kirill@shutemov.name
Fixes:
|
||
 Jiakai Xu
|
45ebe45408 |
riscv/mm: use physical alignment for vmemmap_start_pfn
RISC-V computes vmemmap_start_pfn by rounding phys_ram_base down to VMEMMAP_ADDR_ALIGN. That alignment must therefore be expressed in the physical-address domain. Commit |
||
 Nico Pache
|
d09a8fd521 |
mm/migrate: exclude hugetlb folios from MTHP_STAT_NR_ANON accounting
__folio_migrate_mapping() increments MTHP_STAT_NR_ANON for the destination
folio when `folio_test_anon(folio) && folio_test_large(folio)` is true.
However, hugetlb folios satisfy both conditions despite having a
completely separate accounting system — they use hugetlb_add_anon_rmap()
which does not touch mTHP stats, and their free path also bypasses the
mTHP decrement in __free_pages_prepare().
This causes MTHP_STAT_NR_ANON to be incremented on each hugetlb migration
without a corresponding decrement, permanently inflating the nr_anon
counter.
Add a !folio_test_hugetlb() check to __folio_migrate_mapping() so that
only actual mTHP folios are counted.
Link: https://lore.kernel.org/20260717064502.1980173-3-npache@redhat.com
Fixes:
|
||
|
Nico Pache
|
4bd0c3515a |
mm: decrement MTHP_STAT_NR_ANON in free_zone_device_folio()
Patch series "mm: fix PMD level mTHP accounting bugs", v2.
While running selftests I noticed the PMD level per-mTHP stats (nr_anon)
remained elevated after each run. After further investigation I noticed
this accounting error occurs for both the migration.private_anon_htlb_test
and the HMM tests.
In the HMM case this is due to folio_add_new_anon_rmap() incrementing the
mTHP stats, but never containing a corresponding decrement in
free_zone_device_folio(). We solve this by making sure to decrement the
counter when freeing device memory.
In the migration case, we are incrementing this counter without first
checking whether this folio is a hugetlb folio, which relies on a separate
accounting system. We solve this by adding the proper hugetlb check
before incrementing this counter.
With these changes in place, the two tests no longer cause elevated PMD
level accounting issues.
This patch (of 2):
When a zone device folio is mapped as anonymous, folio_add_new_anon_rmap()
increments MTHP_STAT_NR_ANON. The corresponding decrement lives in
__free_pages_prepare() in page_alloc.c, but zone device folios are freed
via free_zone_device_folio() which never calls __free_pages_prepare().
This causes nr_anon to remain permanently elevated after zone device
folios are freed.
Add the missing mod_mthp_stat() decrement to free_zone_device_folio() so
that the counter is properly balanced.
Link: https://lore.kernel.org/20260717064502.1980173-1-npache@redhat.com
Link: https://lore.kernel.org/20260717064502.1980173-2-npache@redhat.com
Fixes:
|
||
|
Breno Leitao
|
1833ce36b3 |
mm: memcg: initialize *locked in memcg1_oom_prepare() stub
mem_cgroup_oom() passes an uninitialized "locked" to memcg1_oom_prepare()
and reads it back in memcg1_oom_finish():
bool locked, ret;
...
if (!memcg1_oom_prepare(memcg, &locked))
return false;
ret = mem_cgroup_out_of_memory(memcg, mask, order);
memcg1_oom_finish(memcg, locked);
This relies on memcg1_oom_prepare() setting *locked whenever it returns
true. The CONFIG_MEMCG_V1=y version does, but the stub used when
CONFIG_MEMCG_V1=n returns true without touching *locked, so
memcg1_oom_finish() consumes an uninitialized value. On a memcg OOM this
is reported by UBSAN:
UBSAN: invalid-load in mm/memcontrol.c:1932:27
load of value 0 is not a valid value for type 'bool' (aka '_Bool')
Initialize *locked to false in the stub; with cgroup v1 compiled out there
is no OOM lock to take.
Link: https://lore.kernel.org/20260716-memcg-oom-uninit-locked-v2-1-63631d878eb4@debian.org
Fixes:
|
||
 Linus Torvalds
|
62cc902415 |
Merge tag 'mm-hotfixes-stable-2026-07-27-14-18' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton: "13 hotfixes. All are cc:stable. 11 are for MM. All are singletons - please see the changelogs for details" * tag 'mm-hotfixes-stable-2026-07-27-14-18' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: fs/proc/task_mmu: fix PAGEMAP_SCAN written state for PMD holes mm/hugetlb: fix list corruption in allocate_file_region_entries() mm: mglru: fix stale batch updates after memcg reparenting selftest: fix headers in fclog.c ocfs2: fix boundary check in ocfs2_check_dir_entry() to use buffer offset mm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk() mm/util: don't read __page_2 for order-1 folios in snapshot_page() mm/hugetlb: fix swap entry corruption when clearing uffd-wp at fork() mm: migrate_device: fix pte_pfn/pte_dirty called on non-present PTE fs/proc/task_mmu: fix PAGEMAP_SCAN written state for unpopulated ptes userfaultfd: wait on source PMD during UFFDIO_MOVE lib: test_hmm: use device devt for coherent device range selection mm/vmstat: fold stranded per-cpu node stats when a node comes online |
||
|
Linus Torvalds
|
aa6fc3defb |
Merge tag 'for-next-keys-7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd
Pull keys fixes from Jarkko Sakkinen: - An unprivileged keyring whose keys collide through the description-chunk path can drive assoc_array node splitting into an out-of-bounds slot write. Fix it. - Fix the DCP trusted keys backend * tag 'for-next-keys-7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd: assoc_array: trim the final shortcut word using the current chunk end keys: make keyring key-chunk byte order agree with keyring_diff_objects() keys: fix out-of-bounds read in keyring_get_key_chunk() KEYS: trusted: dcp: fix key_len validation and calc_blob_len() return type |
||
|
Linus Torvalds
|
e895a6fc20 |
Merge tag 'erofs-for-7.2-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull erofs fixes from Gao Xiang:
"Fix a regression in page cache sharing which can cause a NULL pointer
dereference, and limit LZMA stream memory usage on systems with many
CPUs.
- Keep a valid f_path for page cache sharing to fix a recent
mincore() NULL pointer dereference
- Limit LZMA stream pool size when too many processors are available
- Sync up with Hongbo Li's latest email address"
* tag 'erofs-for-7.2-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: cap LZMA stream pool size
erofs: ensure valid f_path for page cache sharing
MAINTAINERS: update Hongbo Li's email address
|
||
|
Linus Torvalds
|
e63c75f72f |
Merge tag 'pinctrl-v7.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pin control fixes from Linus Walleij:
"The most interesting commit is the S4 fix for AMD, which probably is
helpful to a whole bunch of important machines.
- Wakeup nits on the Qualcomm SC8280XP
- Double-free issues on the device tree parsing error path
- Fixup of the S4 sleep state handling on AMD pin control
- Missing Kconfig select REGMAP_MMIO for the Microchip driver leading
to compile stalls
- Missing Kconfig select GENERIC_PINCONF for the Bitmain BM1880
leading to compile stalls"
* tag 'pinctrl-v7.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
pinctrl: bm1880: add missing select GENERIC_PINCONF
pinctrl-amd: Don't clear S4 wake bits at probe
pinctrl: microchip-sgpio: add missing select REGMAP_MMIO
pinctrl: devicetree: don't free uninitialized dev_name on error path
pinctrl: qcom: sc8280xp: Add missing wakeup entries for GPIO143/151
pinctrl: qcom: Unconditionally mark gpio as wakeup enable
|
||
 Michael Bommarito
|
c9b47e6b23 |
erofs: cap LZMA stream pool size
fs/erofs/decompressor_lzma.c sizes the module-global MicroLZMA stream
pool from num_possible_cpus() when the lzma_streams module parameter is
unset, then z_erofs_load_lzma_config() preallocates one image-supplied
dictionary per stream, accepting dictionaries up to 8 MiB. On high-CPU
systems, a small EROFS image can pin hundreds of MiB of vmalloc-backed
decoder state until the erofs module is unloaded.
Impact: An EROFS image mounted by the system can pin up to 8 MiB of
vmalloc memory per LZMA stream, either as intended or unexpectedly.
Bound the default stream count by a new
CONFIG_EROFS_FS_ZIP_LZMA_DEFAULT_MAX_STREAMS option, default 16, so the
worst-case default preallocation is 128 MiB if the number of CPUs is no
less than 16 while preserving the existing per-image dictionary limit.
An explicit lzma_streams module parameter is still honoured as-is, so
administrators who deliberately size the pool are not affected.
Fixes:
|
||
 Gao Xiang
|
96b2dbbe58 |
erofs: ensure valid f_path for page cache sharing
Previously, backing files for page cache sharing were set up with
f_path left as NULL (only f_inode was valid). It worked, but a recent
mincore fix relies on f_path.mnt and crashes (found by "erofs/028" on
7.2-rc4):
BUG: kernel NULL pointer dereference, address: 0000000000000018
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP PTI
CPU: 3 UID: 0 PID: 675528 Comm: fincore Not tainted 7.2.0-rc4-00002-g[]-dirty #1 PREEMPT(lazy)
Hardware name: Red Hat KVM, BIOS 1.16.0-4.al8 04/01/2014
RIP: 0010:__do_sys_mincore+0xc0/0x2c0
...
Specify valid paths using valid disconnected dentries together with
erofs_ishare_mnt instead of leaving f_path empty, so they are more
like real backing files in a pseudo filesystem and standard
backing_file_open() can be used directly.
Fixes:
|
||
|
Linus Torvalds
|
f5098b6bae | Linux 7.2-rc5 v7.2-rc5 | ||
|
Linus Torvalds
|
4235cb24ec |
Merge tag 'vfs-7.2-rc5.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
- vfs: Preserve the ACL_DONT_CACHE state in forget_cached_acl().
ACL_DONT_CACHE is meant to be a permanent opt-out from ACL caching
which FUSE relies on for servers that don't negotiate FUSE_POSIX_ACL.
The helper replaced it with ACL_NOT_CACHED, silently re-enabling the
cache, and as fuse doesn't invalidate the cache for such servers a
properly timed get_acl() returned stale ACLs. Comes with a fuse
selftest reproducing this.
- pidfs:
- Preserve PIDFD_THREAD when a thread pidfd is reopened via
open_by_handle_at(). PIDFD_THREAD shares the O_EXCL bit which
do_dentry_open() strips after the flags have been validated, so
the reopened pidfd silently became a process pidfd. Comes with a
selftest.
- Add a pidfs_dentry_open() helper so the regular pidfd allocation
path and the file handle path share the code that forces O_RDWR
and reapplies the pidfd flags that do_dentry_open() strips.
- Handle FS_IOC32_GETVERSION in the compat ioctl path.
- Make pidfs_ino_lock static.
- iomap:
- Fix the block range calculation in ifs_clear_range_dirty() so a
partial clear doesn't drop the dirty state of blocks the range
only partially covers.
- Support invalidating partial folios so a partial truncate or hole
punch with blocksize < foliosize doesn't leave stale dirty bits
behind.
- Only set did_zero when iomap_zero_iter() actually zeroed
something.
- Guard ifs_set_range_dirty() and ifs_set_range_uptodate() against
zero-length ranges where the unsigned last-block calculation
underflows and bitmap_set() writes far beyond the ifs->state
allocation.
- Don't merge ioends with different io_private values as the merge
could leak or corrupt the private data of the individual ioends.
- exec:
- Raise bprm->have_execfd only once the binfmt_misc interpreter has
actually been opened. The flag was set as soon as a matching 'O'
or 'C' entry was found. If the interpreter open failed with
ENOEXEC the exec fell through to the next binary format with
have_execfd raised but no executable staged and begin_new_exec()
NULL derefed past the point of no return.
- Fix an unsigned loop counter wrap in transfer_args_to_stack() on
nommu. An overlong argument or environment string pushes bprm->p
below PAGE_SIZE, the stop index becomes zero, and the loop never
terminates, wrapping its counter and copying garbage from in
front of the page array into the new process stack.
- Make binfmt_elf_fdpic only honour the first PT_INTERP like
binfmt_elf does. Each additional PT_INTERP overwrote the previous
interpreter, leaking the name allocation and the interpreter file
reference together with the write denial open_exec() took,
leaving the file unwritable for as long as the system runs.
- overlayfs:
- Compare the full escaped xattr prefix including the trailing dot.
An xattr like "trusted.overlay.overlayfoo" was misclassified as
an escaped overlay xattr.
- Check read access to the copy_file_range() source with the
source's mounter credentials.
- super: Thawing a filesystem whose block device was frozen with
bdev_freeze() deadlocked. Dropping the last block layer freeze
reference from under s_umount ends up in fs_bdev_thaw() which
reacquires s_umount on the same task. Pin the superblock with an
active reference instead and call bdev_thaw() without holding
s_umount.
- procfs: Return EACCES instead of success when the ptrace access check
for namespace links fails.
- afs: Use afs_dir_get_block() rather than afs_dir_find_block() for
block 0 in afs_edit_dir_remove(), matching afs_edit_dir_add().
- Push the memcg gating of ->nr_cached_objects() down into the btrfs
and shmem callbacks instead of skipping every callback during
non-root memcg reclaim. The blanket check short-circuited XFS whose
inode reclaim hook is intentionally driven from per-memcg contexts to
free memcg-charged slab.
- eventpoll: Pin files while checking reverse paths.
Since struct file became SLAB_TYPESAFE_BY_RCU a concurrent close
could free and recycle the file under the check which then took and
dropped the f_lock of whatever live file now occupies that slot.
* tag 'vfs-7.2-rc5.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (24 commits)
super: fix emergency thaw deadlock on frozen block devices
pidfs: make pidfs_ino_lock static
eventpoll: pin files while checking reverse paths
fs: push nr_cached_objects memcg gating into individual filesystems
afs: Fix afs_edit_dir_remove() to get, not find, block 0
iomap: prevent ioend merge when io_private differs
iomap: add comments for ifs_clear/set_range_dirty()
iomap: fix out-of-bounds bitmap_set() with zero-length range
iomap: fix incorrect did_zero setting in iomap_zero_iter()
iomap: support invalidating partial folios
iomap: correct the range of a partial dirty clear
fs/super: fix emergency thaw double-unlock of s_umount
pidfs: handle FS_IOC32_GETVERSION in compat ioctl
ovl: check access to copy_file_range source with src mounter creds
proc: Fix broken error paths for namespace links
pidfs: add pidfs_dentry_open() helper
selftests/pidfd: check PIDFD_THREAD survives open_by_handle_at()
pidfs: preserve thread pidfds reopened by file handle
ovl: fix trusted xattr escape prefix matching
selftests/fuse: add ACL_DONT_CACHE regression test
...
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Linus Torvalds
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72841e8e83 |
Merge tag 'spi-fix-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi fixes from Mark Brown: "Just a couple of small bits for the SpacemiT driver - one small fix, and a new compatible in the DT binding" * tag 'spi-fix-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: spi: dt-bindings: spacemit: add K3 SPI compatible spi: spacemit: Correct TX FIFO slot calculation |
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Linus Torvalds
|
e6bfeebfe1 |
Merge tag 'regulator-fix-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator fixes from Mark Brown: "One driver specific fix where one of the MediaTek drivers duplicated some core code buggily, and a core fix for an ordering issue on startup where we could end up configuring a voltage outside of constraints due to the order in which we applied constraints" * tag 'regulator-fix-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: regulator: core: clamp voltage constraints before applying apply_uV regulator: mt6358: use regmap helper to read fixed LDO calibration |
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Linus Torvalds
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09b2124a47 |
Merge tag 'char-misc-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH: "Here are a number of small char/misc/etc driver fixes for 7.2-rc5 that resolve a bunch of different reported issues. Included in here are: - rust_binder error message reporting fix - stratix10-svc firmware driver fixes - mei driver fix - intel_th hardware tracing driver fix - comedi driver fix - uio_hv_generic driver fix - ntsync selftest fix - nsm misc driver fix - some MAINTAINER file updates All of these have been in linux-next for over a week with no reported issues" * tag 'char-misc-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: MAINTAINERS: Update wine-devel list address rust_binder: only print failure if error has source intel_th: fix MSC output device reference leak misc: nsm: pin the module while the device is open mei: bus: access mei_device under device_lock on cleanup misc: nsm: only unlock nsm_dev on post-lock error paths selftests: ntsync: correct CONFIG_NTSYNC name comedi: comedi_parport: deal with premature interrupt uio_hv_generic: Bind to FCopy device by default MAINTAINERS: Add Greg Kroah-Hartman to GPIB firmware: stratix10-svc: fix teardown order in remove to prevent race firmware: stratix10-svc: handle NO_RESPONSE in async poll firmware: stratix10-svc: fix FCS SMC call kernel-doc firmware: stratix10-svc: fix memory leaks and list corruption bugs |
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Linus Torvalds
|
516e2cb010 |
Merge tag 'staging-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging driver fixes from Greg KH: "Here are two small staging driver fixes for 7.2-rc5. They both resolve some reported bugs in the rtl8723bs staging driver and have been in linux-next for over a week with no reported issues" * tag 'staging-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: staging: rtl8723bs: fix OOB reads in rtw_get_wps_ie() staging: rtl8723bs: fix inverted HT40 secondary channel offset |
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Linus Torvalds
|
3d0a01cad2 |
Merge tag 'tty-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull serial driver fixes from Greg KH:
"Here are two small serial driver fixes for 7.2-rc5. They are:
- sc16is7xx get_direction() callback fix, which resolves a
user-triggerable warning in the driver
- NULL pointer dereference on some platforms using the 8250_mid
serial driver
Both have been in linux-next for over a week with no reported issues"
* tag 'tty-7.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: sc16is7xx: implement gpio get_direction() callback
serial: 8250_mid: Fix NULL function pointer dereference on DNV/ICX-D/SNR platforms
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