thread_group_empty(tsk) is only possible if tsk is a group leader, and
thread_group_empty() already does the thread_group_leader() check.
So it makes no sense to check "thread_group_leader() &&
thread_group_empty()"; thread_group_empty() alone is enough.
Link: https://lkml.kernel.org/r/aZsfeegKZPZZszJh@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Kees Cook <kees@kernel.org>
Cc; Deepanshu Kartikey <kartikey406@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
msgque kselftest uses msgrcv(..., MSG_COPY) to copy messages. When the
kernel is built without CONFIG_CHECKPOINT_RESTORE, prepare_copy() is
stubbed out and msgrcv() returns -ENOSYS. The test currently reports this
as a failure even though it is simply a missing feature/configuration.
Skip the test when msgrcv() fails with ENOSYS.
Link: https://lkml.kernel.org/r/20260210135359.178636-1-jouyeol8739@gmail.com
Signed-off-by: UYeol Jo <jouyeol8739@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Easier to add new entries. It was sorted when added in 66b47b4a9d, but
later got wrong order for few entries. Sorted with en_US.UTF-8 locale.
Link: https://lkml.kernel.org/r/20260212144005.45052-1-pvorel@suse.cz
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Cc: Jonathan Camerom <Jonathan.Cameron@huawei.com>
Cc: WangYuli <wangyuli@uniontech.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
However there's a convention of assuming that __init-time allocations
cannot fail. Because if a kmalloc() were to fail at this time, the kernel
is hopelessly messed up anyway. So simply panic() if that kmalloc failed,
then make that 350-byte buffer __initdata.
Link: https://lkml.kernel.org/r/20260223035914.4033-1-rioo.tsukatsukii@gmail.com
Signed-off-by: Rio <rioo.tsukatsukii@gmail.com>
Cc: Joel Granados <joel.granados@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Wang Jinchao <wangjinchao600@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The buffer used to hold the taint string is statically allocated, which
requires updating whenever a new taint flag is added.
Instead, allocate the exact required length at boot once the allocator is
available in an init function. The allocation sums the string lengths in
taint_flags[], along with space for separators and formatting.
print_tainted() is switched to use this dynamically allocated buffer.
If allocation fails, print_tainted() warns about the failure and continues
to use the original static buffer as a fallback.
Link: https://lkml.kernel.org/r/20260222140804.22225-1-rioo.tsukatsukii@gmail.com
Signed-off-by: Rio <rioo.tsukatsukii@gmail.com>
Cc: Joel Granados <joel.granados@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Wang Jinchao <wangjinchao600@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The verbose 'Tainted: ...' string in print_tainted_seq can total to 327
characters while the buffer defined in _print_tainted is 320 bytes.
Increase its size to 350 characters to hold all flags, along with some
headroom.
[akpm@linux-foundation.org: fix spello, add comment]
Link: https://lkml.kernel.org/r/20260220151500.13585-1-rioo.tsukatsukii@gmail.com
Signed-off-by: Rio <rioo.tsukatsukii@gmail.com>
Cc: Joel Granados <joel.granados@kernel.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Wang Jinchao <wangjinchao600@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The output of bloat-o-meter already uses the words 'old' and 'new' for
symbol size in the table header, so reflect that in the corresponding
argument names.
Link: https://lkml.kernel.org/r/20260212213941.3984330-1-vkoskiv@gmail.com
Signed-off-by: Valtteri Koskivuori <vkoskiv@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The correct passive of "to bind" is "bound", not "binded". This is often
used in the context of the BSD socket bind(2) operation.
Link: https://lkml.kernel.org/r/20260214140854.42247-1-gnoack3000@gmail.com
Signed-off-by: Günther Noack <gnoack3000@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
task_sig() already wraps the SigQ rlimit read in an explicit RCU read-side
critical section. Drop the stale FIXME comment and keep using
task_ucounts() for the ucounts access.
No functional change.
Link: https://lkml.kernel.org/r/20260215124511.14227-1-jaime.saguillo@gmail.com
Signed-off-by: Jaime Saguillo Revilla <jaime.saguillo@gmail.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
During initialization of a VRF device, the VRF driver creates two dst
entries (for IPv4 and IPv6). They are attached to locally generated
packets that are transmitted out of the VRF ports (via the
l3mdev_l3_out() hook). Their purpose is to redirect packets towards the
VRF device instead of having the packets egress directly out of the VRF
ports. This is useful, for example, when a queuing discipline is
configured on the VRF device.
In order to avoid a NULL pointer dereference, commit b0e95ccdd7 ("net:
vrf: protect changes to private data with rcu") made the pointers to the
dst entries RCU protected. As far as I can tell, this was needed because
back then the dst entries were released (and the pointers reset to NULL)
before removing the VRF ports.
Later on, commit f630c38ef0 ("vrf: fix bug_on triggered by rx when
destroying a vrf") moved the removal of the VRF ports to the VRF
device's dellink() callback. As such, the tear down sequence of a VRF
device looks as follows:
1. VRF ports are removed.
2. VRF device is unregistered.
a. Device is closed.
b. An RCU grace period passes.
c. ndo_uninit() is called.
i. dst entries are released.
Given the above, the Tx path will always see the same fully initialized
dst entries and will never race with the ndo_uninit() callback.
Therefore, there is no need to make the pointers to the dst entries RCU
protected. Remove it as well as the unnecessary NULL checks in the Tx
path.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260326203233.1128554-4-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Use dst_dev_put() to clean up the device referenced by the dst entry
instead of partially open coding it. Internally, the helper uses the
blackhole device instead of the loopback device.
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260326203233.1128554-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The VRF driver always allocates an IPv4 dst entry for a VRF device and
prevents the device from being registered if the allocation fails.
Therefore, there is no need to check if the entry exists when tearing
down a VRF device. Remove the check.
Note that the same is not true for the IPv6 dst entry. Its creation can
be skipped if IPv6 is administratively disabled (i.e.,
'ipv6.disable=1').
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20260326203233.1128554-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Laurent Pinchart says:
====================
net: stmmac: Disable EEE on i.MX
This small patch series fixes a long-standing interrupt storm issue with
stmmac on NXP i.MX platforms.
The initial attempt to fix^Wwork around the problem in DT ([1]) was
painfully but rightfully rejected by Russell, who helped me investigate
the issue in depth. It turned out that the root cause is a mistake in
how interrupts are wired in the SoC, a hardware bug that has been
replicated in all i.MX SoCs that integrate an stmmac. The only viable
solution is to disable EEE on those devices.
Individual patches explain the issue in more details. Patch 1/2,
authored by Russell, adds a new STMMAC_FLAG to disable EEE, and patch
2/2 sets the flag for i.MX platforms.
[1] https://lore.kernel.org/r/20251026122905.29028-1-laurent.pinchart@ideasonboard.com
====================
Link: https://patch.msgid.link/20260325210003.2752013-1-laurent.pinchart@ideasonboard.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The i.MX8MP suffers from an interrupt storm related to the stmmac and
EEE. A long and tedious analysis ([1]) concluded that the SoC wires the
stmmac lpi_intr_o signal to an OR gate along with the main dwmac
interrupts, which causes an interrupt storm for two reasons.
First, there's a race condition due to the interrupt deassertion being
synchronous to the RX clock domain:
- When the PHY exits LPI mode, it restarts generating the RX clock
(clk_rx_i input signal to the GMAC).
- The MAC detects exit from LPI, and asserts lpi_intr_o. This triggers
the ENET_EQOS interrupt.
- Before the CPU has time to process the interrupt, the PHY enters LPI
mode again, and stops generating the RX clock.
- The CPU processes the interrupt and reads the GMAC4_LPI_CTRL_STATUS
registers. This does not clear lpi_intr_o as there's no clk_rx_i.
An attempt was made to fixing the issue by not stopping RX_CLK in Rx LPI
state ([2]). This alleviates the symptoms but doesn't fix the issue.
Since lpi_intr_o takes four RX_CLK cycles to clear, an interrupt storm
can still occur during that window. In 1000T mode this is harder to
notice, but slower receive clocks cause hundreds to thousands of
spurious interrupts.
Fix the issue by disabling EEE completely on i.MX8MP.
[1] https://lore.kernel.org/all/20251026122905.29028-1-laurent.pinchart@ideasonboard.com/
[2] https://lore.kernel.org/all/20251123053518.8478-1-laurent.pinchart@ideasonboard.com/
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/20260325210003.2752013-3-laurent.pinchart@ideasonboard.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Some platforms have problems when EEE is enabled, and thus need a way
to disable stmmac EEE support. Add a flag before the other LPI related
flags which tells stmmac to avoid populating the phylink LPI
capabilities, which causes phylink to call phy_disable_eee() for any
PHY that is attached to the affected phylink instance.
iMX8MP is an example - the lpi_intr_o signal is wired to an OR gate
along with the main dwmac interrupts. Since lpi_intr_o is synchronous
to the receive clock domain, and takes four clock cycles to clear, this
leads to interrupt storms as the interrupt remains asserted for some
time after the LPI control and status register is read.
This problem becomes worse when the receive clock from the PHY stops
when the receive path enters LPI state - which means that lpi_intr_o
can not deassert until the clock restarts. Since the LPI state of the
receive path depends on the link partner, this is out of our control.
We could disable RX clock stop at the PHY, but that doesn't get around
the slow-to-deassert lpi_intr_o mentioned in the above paragraph.
Previously, iMX8MP worked around this by disabling gigabit EEE, but
this is insufficient - the problem is also visible at 100M speeds,
where the receive clock is slower.
There is extensive discussion and investigation in the thread linked
below, the result of which is summarised in this commit message.
Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Closes: https://lore.kernel.org/r/20251026122905.29028-1-laurent.pinchart@ideasonboard.com
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Tested-by: Ovidiu Panait <ovidiu.panait.rb@renesas.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Link: https://patch.msgid.link/20260325210003.2752013-2-laurent.pinchart@ideasonboard.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Wei Fang says:
====================
net: enetc: add more checks to enetc_set_rxfh()
ENETC only supports Toeplitz algorithm, and VFs do not support setting
the RSS key, but enetc_set_rxfh() does not check these constraints and
silently accepts unsupported configurations. This may mislead users or
tools into believing that the requested RSS settings have been
successfully applied. So add checks to reject unsupported hash functions
and RSS key updates on VFs, and return "-EOPNOTSUPP" to user space.
====================
Link: https://patch.msgid.link/20260326075233.3628047-1-wei.fang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
VFs do not have privilege to configure the RSS key because the registers
are owned by the PF. Currently, if VF attempts to configure the RSS key,
enetc_set_rxfh() simply skips the configuration and does not generate a
warning, which may mislead users into thinking the feature is supported.
To improve this situation, add a check to reject RSS key configuration
on VFs.
Fixes: d382563f54 ("enetc: Add RFS and RSS support")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Clark Wang <xiaoning.wang@nxp.com>
Reviewed-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Link: https://patch.msgid.link/20260326075233.3628047-3-wei.fang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Both ENETC v1 and v4 only provide Toeplitz RSS support. This patch adds
a validation check to reject attempts to configure other RSS algorithms,
avoiding misleading configuration options for users.
Fixes: d382563f54 ("enetc: Add RFS and RSS support")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Clark Wang <xiaoning.wang@nxp.com>
Reviewed-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Link: https://patch.msgid.link/20260326075233.3628047-2-wei.fang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In commit 8110633db4 ("net: sfp-bus: allow SFP quirks to override
Autoneg and pause bits") we moved the setting of Autoneg and pause bits
before the call to SFP quirk when parsing SFP module support.
Since the quirk for Ubiquiti U-Fiber Instant SFP module zeroes the
support bits and sets 1000baseX_Full only, the above mentioned commit
changed the overall computed support from
1000baseX_Full, Autoneg, Pause, Asym_Pause
to just
1000baseX_Full.
This broke the SFP module for mvneta, which requires Autoneg for
1000baseX since commit c762b7fac1 ("net: mvneta: deny disabling
autoneg for 802.3z modes").
Fix this by setting back the Autoneg, Pause and Asym_Pause bits in the
quirk.
Fixes: 8110633db4 ("net: sfp-bus: allow SFP quirks to override Autoneg and pause bits")
Signed-off-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/20260326122038.2489589-1-kabel@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Previously we stored the end of the current VMA in curr_end, and then upon
iterating to the next VMA updated curr_start to curr_end to advance to the
next VMA.
However, this doesn't take into account the fact that a VMA might be
updated due to a merge by vma_modify_flags(), which can result in curr_end
being stale and thus, upon setting curr_start to curr_end, ending up with
an incorrect curr_start on the next iteration.
Resolve the issue by setting curr_end to vma->vm_end unconditionally to
ensure this value remains updated should this occur.
While we're here, eliminate this entire class of bug by simply setting
const curr_[start/end] to be clamped to the input range and VMAs, which
also happens to simplify the logic.
Link: https://lkml.kernel.org/r/20260327173104.322405-1-ljs@kernel.org
Fixes: 6c2da14ae1 ("mm/mseal: rework mseal apply logic")
Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Reported-by: Antonius <antonius@bluedragonsec.com>
Closes: https://lore.kernel.org/linux-mm/CAK8a0jwWGj9-SgFk0yKFh7i8jMkwKm5b0ao9=kmXWjO54veX2g@mail.gmail.com/
Suggested-by: David Hildenbrand (ARM) <david@kernel.org>
Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Jeff Xu <jeffxu@chromium.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
follow_pfnmap_start() suffers from two problems:
(1) We are not re-fetching the pmd/pud after taking the PTL
Therefore, we are not properly stabilizing what the lock actually
protects. If there is concurrent zapping, we would indicate to the
caller that we found an entry, however, that entry might already have
been invalidated, or contain a different PFN after taking the lock.
Properly use pmdp_get() / pudp_get() after taking the lock.
(2) pmd_leaf() / pud_leaf() are not well defined on non-present entries
pmd_leaf()/pud_leaf() could wrongly trigger on non-present entries.
There is no real guarantee that pmd_leaf()/pud_leaf() returns something
reasonable on non-present entries. Most architectures indeed either
perform a present check or make it work by smart use of flags.
However, for example loongarch checks the _PAGE_HUGE flag in pmd_leaf(),
and always sets the _PAGE_HUGE flag in __swp_entry_to_pmd(). Whereby
pmd_trans_huge() explicitly checks pmd_present(), pmd_leaf() does not do
that.
Let's check pmd_present()/pud_present() before assuming "the is a present
PMD leaf" when spotting pmd_leaf()/pud_leaf(), like other page table
handling code that traverses user page tables does.
Given that non-present PMD entries are likely rare in VM_IO|VM_PFNMAP, (1)
is likely more relevant than (2). It is questionable how often (1) would
actually trigger, but let's CC stable to be sure.
This was found by code inspection.
Link: https://lkml.kernel.org/r/20260323-follow_pfnmap_fix-v1-1-5b0ec10872b3@kernel.org
Fixes: 6da8e9634b ("mm: new follow_pfnmap API")
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
damon_sysfs_repeat_call_fn() calls damon_sysfs_upd_tuned_intervals(),
damon_sysfs_upd_schemes_stats(), and
damon_sysfs_upd_schemes_effective_quotas() without checking contexts->nr.
If nr_contexts is set to 0 via sysfs while DAMON is running, these
functions dereference contexts_arr[0] and cause a NULL pointer
dereference. Add the missing check.
For example, the issue can be reproduced using DAMON sysfs interface and
DAMON user-space tool (damo) [1] like below.
$ sudo damo start --refresh_interval 1s
$ echo 0 | sudo tee \
/sys/kernel/mm/damon/admin/kdamonds/0/contexts/nr_contexts
Link: https://patch.msgid.link/20260320163559.178101-3-objecting@objecting.org
Link: https://lkml.kernel.org/r/20260321175427.86000-4-sj@kernel.org
Link: https://github.com/damonitor/damo [1]
Fixes: d809a7c64b ("mm/damon/sysfs: implement refresh_ms file internal work")
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [6.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Multiple sysfs command paths dereference contexts_arr[0] without first
verifying that kdamond->contexts->nr == 1. A user can set nr_contexts to
0 via sysfs while DAMON is running, causing NULL pointer dereferences.
In more detail, the issue can be triggered by privileged users like
below.
First, start DAMON and make contexts directory empty
(kdamond->contexts->nr == 0).
# damo start
# cd /sys/kernel/mm/damon/admin/kdamonds/0
# echo 0 > contexts/nr_contexts
Then, each of below commands will cause the NULL pointer dereference.
# echo update_schemes_stats > state
# echo update_schemes_tried_regions > state
# echo update_schemes_tried_bytes > state
# echo update_schemes_effective_quotas > state
# echo update_tuned_intervals > state
Guard all commands (except OFF) at the entry point of
damon_sysfs_handle_cmd().
Link: https://lkml.kernel.org/r/20260321175427.86000-3-sj@kernel.org
Fixes: 0ac32b8aff ("mm/damon/sysfs: support DAMOS stats")
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [5.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "mm/damon/sysfs: fix memory leak and NULL dereference
issues", v4.
DAMON_SYSFS can leak memory under allocation failure, and do NULL pointer
dereference when a privileged user make wrong sequences of control. Fix
those.
This patch (of 3):
When damon_sysfs_new_test_ctx() fails in damon_sysfs_commit_input(),
param_ctx is leaked because the early return skips the cleanup at the out
label. Destroy param_ctx before returning.
Link: https://lkml.kernel.org/r/20260321175427.86000-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20260321175427.86000-2-sj@kernel.org
Fixes: f0c5118ebb ("mm/damon/sysfs: catch commit test ctx alloc failure")
Signed-off-by: Josh Law <objecting@objecting.org>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> [6.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The swap readahead path was recently refactored and while doing this, the
order between the charging of the folio in the memcg and the addition of
the folio in the swap cache was inverted.
Since the accounting of the folio is done while adding the folio to the
swap cache and the folio is not charged in the memcg yet, the accounting
is then done at the node level, which is wrong.
Fix this by charging the folio in the memcg before adding it to the swap cache.
Link: https://lkml.kernel.org/r/20260320050601.1833108-1-alex@ghiti.fr
Fixes: 2732acda82 ("mm, swap: use swap cache as the swap in synchronize layer")
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: Kairui Song <kasong@tencent.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Baoquan He <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
On arm64 server, we found folio that get from migration entry isn't locked
in softleaf_to_folio(). This issue triggers when mTHP splitting and
zap_nonpresent_ptes() races, and the root cause is lack of memory barrier
in softleaf_to_folio(). The race is as follows:
CPU0 CPU1
deferred_split_scan() zap_nonpresent_ptes()
lock folio
split_folio()
unmap_folio()
change ptes to migration entries
__split_folio_to_order() softleaf_to_folio()
set flags(including PG_locked) for tail pages folio = pfn_folio(softleaf_to_pfn(entry))
smp_wmb() VM_WARN_ON_ONCE(!folio_test_locked(folio))
prep_compound_page() for tail pages
In __split_folio_to_order(), smp_wmb() guarantees page flags of tail pages
are visible before the tail page becomes non-compound. smp_wmb() should
be paired with smp_rmb() in softleaf_to_folio(), which is missed. As a
result, if zap_nonpresent_ptes() accesses migration entry that stores tail
pfn, softleaf_to_folio() may see the updated compound_head of tail page
before page->flags.
This issue will trigger VM_WARN_ON_ONCE() in pfn_swap_entry_folio()
because of the race between folio split and zap_nonpresent_ptes()
leading to a folio incorrectly undergoing modification without a folio
lock being held.
This is a BUG_ON() before commit 93976a2034 ("mm: eliminate further
swapops predicates"), which in merged in v6.19-rc1.
To fix it, add missing smp_rmb() if the softleaf entry is migration entry
in softleaf_to_folio() and softleaf_to_page().
[tujinjiang@huawei.com: update function name and comments]
Link: https://lkml.kernel.org/r/20260321075214.3305564-1-tujinjiang@huawei.com
Link: https://lkml.kernel.org/r/20260319012541.4158561-1-tujinjiang@huawei.com
Fixes: e9b61f1985 ("thp: reintroduce split_huge_page()")
Signed-off-by: Jinjiang Tu <tujinjiang@huawei.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Barry Song <baohua@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nanyong Sun <sunnanyong@huawei.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
mana_gd_ring_doorbell() accesses offsets up to DOORBELL_OFFSET_EQ
(0xFF8) + 8 bytes = 4KB within each doorbell page. A db_page_size
smaller than SZ_4K is fundamentally incompatible with the driver:
doorbell pages would overlap and the device cannot function correctly.
Validate db_page_size at the source and fail the
probe early if the value is below SZ_4K. This ensures the doorbell ID
range check in mana_gd_register_device() can rely on db_page_size
being valid.
Fixes: 89fe91c659 ("net: mana: hardening: Validate doorbell ID from GDMA_REGISTER_DEVICE response")
Signed-off-by: Erni Sri Satya Vennela <ernis@linux.microsoft.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260325180423.1923060-1-ernis@linux.microsoft.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add a regression test for the divide-by-zero in rtsc_min() triggered
when m2sm() converts a large m1 value (e.g. 32gbit) to a u64 scaled
slope reaching 2^32. rtsc_min() stores the difference of two such u64
values (sm1 - sm2) in a u32 variable `dsm`, truncating 2^32 to zero
and causing a divide-by-zero oops in the concave-curve intersection
path. The test configures an HFSC class with m1=32gbit d=1ms m2=0bit,
sends a packet to activate the class, waits for it to drain and go
idle, then sends another packet to trigger reactivation through
rtsc_min().
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20260326204310.1549327-2-xmei5@asu.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
m2sm() converts a u32 slope to a u64 scaled value. For large inputs
(e.g. m1=4000000000), the result can reach 2^32. rtsc_min() stores
the difference of two such u64 values in a u32 variable `dsm` and
uses it as a divisor. When the difference is exactly 2^32 the
truncation yields zero, causing a divide-by-zero oops in the
concave-curve intersection path:
Oops: divide error: 0000
RIP: 0010:rtsc_min (net/sched/sch_hfsc.c:601)
Call Trace:
init_ed (net/sched/sch_hfsc.c:629)
hfsc_enqueue (net/sched/sch_hfsc.c:1569)
[...]
Widen `dsm` to u64 and replace do_div() with div64_u64() so the full
difference is preserved.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Weiming Shi <bestswngs@gmail.com>
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260326204310.1549327-1-xmei5@asu.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
While reviewing recent ext4 patch[1], Sashiko raised the following
concern[2]:
> If the filesystem is initially mounted with the discard option,
> deleting files will populate sbi->s_discard_list and queue
> s_discard_work. If it is then remounted with nodiscard, the
> EXT4_MOUNT_DISCARD flag is cleared, but the pending s_discard_work is
> neither cancelled nor flushed.
[1] https://lore.kernel.org/r/20260319094545.19291-1-qiang.zhang@linux.dev/
[2] https://sashiko.dev/#/patchset/20260319094545.19291-1-qiang.zhang%40linux.dev
The concern was valid, but it had nothing to do with the patch[1].
One of the problems with Sashiko in its current (early) form is that
it will detect pre-existing issues and report it as a problem with the
patch that it is reviewing.
In practice, it would be hard to hit deliberately (unless you are a
malicious syzkaller fuzzer), since it would involve mounting the file
system with -o discard, and then deleting a large number of files,
remounting the file system with -o nodiscard, and then immediately
unmounting the file system before the queued discard work has a change
to drain on its own.
Fix it because it's a real bug, and to avoid Sashiko from raising this
concern when analyzing future patches to mballoc.c.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Fixes: 55cdd0af2b ("ext4: get discard out of jbd2 commit kthread contex")
Cc: stable@kernel.org
Commit 4865c768b5 ("ext4: always allocate blocks only from groups
inode can use") restricts what blocks will be allocated for indirect
block based files to block numbers that fit within 32-bit block
numbers.
However, when using a review bot running on the latest Gemini LLM to
check this commit when backporting into an LTS based kernel, it raised
this concern:
If ac->ac_g_ex.fe_group is >= ngroups (for instance, if the goal
group was populated via stream allocation from s_mb_last_groups),
then start will be >= ngroups.
Does this allow allocating blocks beyond the 32-bit limit for
indirect block mapped files? The commit message mentions that
ext4_mb_scan_groups_linear() takes care to not select unsupported
groups. However, its loop uses group = *start, and the very first
iteration will call ext4_mb_scan_group() with this unsupported
group because next_linear_group() is only called at the end of the
iteration.
After reviewing the code paths involved and considering the LLM
review, I determined that this can happen when there is a file system
where some files/directories are extent-mapped and others are
indirect-block mapped. To address this, add a safety clamp in
ext4_mb_scan_groups().
Fixes: 4865c768b5 ("ext4: always allocate blocks only from groups inode can use")
Cc: Jan Kara <jack@suse.cz>
Reviewed-by: Baokun Li <libaokun@linux.alibaba.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://patch.msgid.link/20260326045834.1175822-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
ext4_split_extent_at() retries after ext4_ext_insert_extent() fails by
refinding the original extent and restoring its length. That recovery is
only safe for transient resource failures such as -ENOSPC, -EDQUOT, and
-ENOMEM.
When ext4_ext_insert_extent() fails because the extent tree is already
corrupted, ext4_find_extent() can return a leaf path without p_ext.
ext4_split_extent_at() then dereferences path[depth].p_ext while trying to
fix up the original extent length, causing a NULL pointer dereference while
handling a pre-existing filesystem corruption.
Do not enter the recovery path for corruption errors, and validate p_ext
after refinding the extent before touching it. This keeps the recovery path
limited to cases it can actually repair and turns the syzbot-triggered crash
into a proper corruption report.
Fixes: 716b9c23b8 ("ext4: refactor split and convert extents")
Reported-by: syzbot+1ffa5d865557e51cb604@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1ffa5d865557e51cb604
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: hongao <hongao@uniontech.com>
Link: https://patch.msgid.link/EF77870F23FF9C90+20260324015815.35248-1-hongao@uniontech.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
During code review, Joseph found that ext4_fc_replay_inode() calls
ext4_get_fc_inode_loc() to get the inode location, which holds a
reference to iloc.bh that must be released via brelse().
However, several error paths jump to the 'out' label without
releasing iloc.bh:
- ext4_handle_dirty_metadata() failure
- sync_dirty_buffer() failure
- ext4_mark_inode_used() failure
- ext4_iget() failure
Fix this by introducing an 'out_brelse' label placed just before
the existing 'out' label to ensure iloc.bh is always released.
Additionally, make ext4_fc_replay_inode() propagate errors
properly instead of always returning 0.
Reported-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Fixes: 8016e29f43 ("ext4: fast commit recovery path")
Signed-off-by: Baokun Li <libaokun@linux.alibaba.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260323060836.3452660-1-libaokun@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Currently there is a race in ext4 when reallocating freed inode
resulting in a deadlock:
Task1 Task2
ext4_evict_inode()
handle = ext4_journal_start();
...
if (IS_SYNC(inode))
handle->h_sync = 1;
ext4_free_inode()
ext4_new_inode()
handle = ext4_journal_start()
finds the bit in inode bitmap
already clear
insert_inode_locked()
waits for inode to be
removed from the hash.
ext4_journal_stop(handle)
jbd2_journal_stop(handle)
jbd2_log_wait_commit(journal, tid);
- deadlocks waiting for transaction handle Task2 holds
Fix the problem by removing inode from the hash already in
ext4_clear_inode() by which time all IO for the inode is done so reuse
is already fine but we are still before possibly blocking on transaction
commit.
Reported-by: "Lai, Yi" <yi1.lai@linux.intel.com>
Link: https://lore.kernel.org/all/abNvb2PcrKj1FBeC@ly-workstation
Fixes: 88ec797c46 ("fs: make insert_inode_locked() wait for inode destruction")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260320090428.24899-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Commit b98535d091 ("ext4: fix bug_on in start_this_handle during umount
filesystem") moved ext4_unregister_sysfs() before flushing s_sb_upd_work
to prevent new error work from being queued via /proc/fs/ext4/xx/mb_groups
reads during unmount. However, this introduced a use-after-free because
update_super_work calls ext4_notify_error_sysfs() -> sysfs_notify() which
accesses the kobject's kernfs_node after it has been freed by kobject_del()
in ext4_unregister_sysfs():
update_super_work ext4_put_super
----------------- --------------
ext4_unregister_sysfs(sb)
kobject_del(&sbi->s_kobj)
__kobject_del()
sysfs_remove_dir()
kobj->sd = NULL
sysfs_put(sd)
kernfs_put() // RCU free
ext4_notify_error_sysfs(sbi)
sysfs_notify(&sbi->s_kobj)
kn = kobj->sd // stale pointer
kernfs_get(kn) // UAF on freed kernfs_node
ext4_journal_destroy()
flush_work(&sbi->s_sb_upd_work)
Instead of reordering the teardown sequence, fix this by making
ext4_notify_error_sysfs() detect that sysfs has already been torn down
by checking s_kobj.state_in_sysfs, and skipping the sysfs_notify() call
in that case. A dedicated mutex (s_error_notify_mutex) serializes
ext4_notify_error_sysfs() against kobject_del() in ext4_unregister_sysfs()
to prevent TOCTOU races where the kobject could be deleted between the
state_in_sysfs check and the sysfs_notify() call.
Fixes: b98535d091 ("ext4: fix bug_on in start_this_handle during umount filesystem")
Cc: Jiayuan Chen <jiayuan.chen@linux.dev>
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jiayuan Chen <jiayuan.chen@shopee.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260319120336.157873-1-jiayuan.chen@linux.dev
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Yang Yang says:
====================
bridge/vxlan: harden ND option parsing paths
This series hardens ND option parsing in bridge and vxlan paths.
Patch 1 linearizes the request skb in br_nd_send() before walking ND
options. Patch 2 adds explicit ND option length validation in
br_nd_send(). Patch 3 adds matching ND option length validation in
vxlan_na_create().
====================
Link: https://patch.msgid.link/20260326034441.2037420-1-n05ec@lzu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
vxlan_na_create() walks ND options according to option-provided
lengths. A malformed option can make the parser advance beyond the
computed option span or use a too-short source LLADDR option payload.
Validate option lengths against the remaining NS option area before
advancing, and only read source LLADDR when the option is large enough
for an Ethernet address.
Fixes: 4b29dba9c0 ("vxlan: fix nonfunctional neigh_reduce()")
Cc: stable@vger.kernel.org
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Tested-by: Ao Zhou <n05ec@lzu.edu.cn>
Co-developed-by: Yuan Tan <tanyuan98@outlook.com>
Signed-off-by: Yuan Tan <tanyuan98@outlook.com>
Suggested-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Yang Yang <n05ec@lzu.edu.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260326034441.2037420-4-n05ec@lzu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
br_nd_send() walks ND options according to option-provided lengths.
A malformed option can make the parser advance beyond the computed
option span or use a too-short source LLADDR option payload.
Validate option lengths against the remaining NS option area before
advancing, and only read source LLADDR when the option is large enough
for an Ethernet address.
Fixes: ed842faeb2 ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports")
Cc: stable@vger.kernel.org
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Tested-by: Ao Zhou <n05ec@lzu.edu.cn>
Co-developed-by: Yuan Tan <tanyuan98@outlook.com>
Signed-off-by: Yuan Tan <tanyuan98@outlook.com>
Suggested-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Yang Yang <n05ec@lzu.edu.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260326034441.2037420-3-n05ec@lzu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
br_nd_send() parses neighbour discovery options from ns->opt[] and
assumes that these options are in the linear part of request.
Its callers only guarantee that the ICMPv6 header and target address
are available, so the option area can still be non-linear. Parsing
ns->opt[] in that case can access data past the linear buffer.
Linearize request before option parsing and derive ns from the linear
network header.
Fixes: ed842faeb2 ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports")
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Tested-by: Ao Zhou <n05ec@lzu.edu.cn>
Co-developed-by: Yuan Tan <tanyuan98@outlook.com>
Signed-off-by: Yuan Tan <tanyuan98@outlook.com>
Suggested-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Yang Yang <n05ec@lzu.edu.cn>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260326034441.2037420-2-n05ec@lzu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Now, only EXT4_KUNIT_TESTS=Y testcase will be compiled in 'extents.c'.
To solve this issue, the ext4 test code needs to be decoupled. The
'extents-test' module is compiled into 'ext4-test' module.
Fixes: cb1e0c1d1f ("ext4: kunit tests for extent splitting and conversion")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260314075258.1317579-4-yebin@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
