linux-stable.git/tools, branch v7.0.4

mm: various small mmap_prepare cleanups

2026-05-07T04:14:15+00:00

[ Upstream commit 3e4bb2706817710d9461394da8b75be79981586b ]

Patch series "mm: expand mmap_prepare functionality and usage", v4.

This series expands the mmap_prepare functionality, which is intended to
replace the deprecated f_op->mmap hook which has been the source of bugs
and security issues for some time.

This series starts with some cleanup of existing mmap_prepare logic, then
adds documentation for the mmap_prepare call to make it easier for
filesystem and driver writers to understand how it works.

It then importantly adds a vm_ops->mapped hook, a key feature that was
missing from mmap_prepare previously - this is invoked when a driver which
specifies mmap_prepare has successfully been mapped but not merged with
another VMA.

mmap_prepare is invoked prior to a merge being attempted, so you cannot
manipulate state such as reference counts as if it were a new mapping.

The vm_ops->mapped hook allows a driver to perform tasks required at this
stage, and provides symmetry against subsequent vm_ops->open,close calls.

The series uses this to correct the afs implementation which wrongly
manipulated reference count at mmap_prepare time.

It then adds an mmap_prepare equivalent of vm_iomap_memory() -
mmap_action_simple_ioremap(), then uses this to update a number of drivers.

It then splits out the mmap_prepare compatibility layer (which allows for
invocation of mmap_prepare hooks in an mmap() hook) in such a way as to
allow for more incremental implementation of mmap_prepare hooks.

It then uses this to extend mmap_prepare usage in drivers.

Finally it adds an mmap_prepare equivalent of vm_map_pages(), which lays
the foundation for future work which will extend mmap_prepare to DMA
coherent mappings.

This patch (of 21):

Rather than passing arbitrary fields, pass a vm_area_desc pointer to mmap
prepare functions to mmap prepare, and an action and vma pointer to mmap
complete in order to put all the action-specific logic in the function
actually doing the work.

Additionally, allow mmap prepare functions to return an error so we can
error out as soon as possible if there is something logically incorrect in
the input.

Update remap_pfn_range_prepare() to properly check the input range for the
CoW case.

Also remove io_remap_pfn_range_complete(), as we can simply set up the
fields correctly in io_remap_pfn_range_prepare() and use
remap_pfn_range_complete() for this.

While we're here, make remap_pfn_range_prepare_vma() a little neater, and
pass mmap_action directly to call_action_complete().

Then, update compat_vma_mmap() to perform its logic directly, as
__compat_vma_map() is not used by anything so we don't need to export it.

Also update compat_vma_mmap() to use vfs_mmap_prepare() rather than
calling the mmap_prepare op directly.

Finally, update the VMA userland tests to reflect the changes.

Link: https://lkml.kernel.org/r/cover.1774045440.git.ljs@kernel.org
Link: https://lkml.kernel.org/r/99f408e4694f44ab12bdc55fe0bd9685d3bd1117.1774045440.git.ljs@kernel.org
Signed-off-by: Lorenzo Stoakes (Oracle) 
Acked-by: Vlastimil Babka (SUSE) 
Cc: Alexander Shishkin 
Cc: Alexandre Torgue 
Cc: Al Viro 
Cc: Arnd Bergmann 
Cc: Bodo Stroesser 
Cc: Christian Brauner 
Cc: Clemens Ladisch 
Cc: David Hildenbrand 
Cc: David Howells 
Cc: Dexuan Cui 
Cc: Greg Kroah-Hartman 
Cc: Haiyang Zhang 
Cc: Jan Kara 
Cc: Jann Horn 
Cc: Jonathan Corbet 
Cc: K. Y. Srinivasan 
Cc: Liam Howlett 
Cc: Long Li 
Cc: Marc Dionne 
Cc: "Martin K. Petersen" 
Cc: Maxime Coquelin 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Miquel Raynal 
Cc: Pedro Falcato 
Cc: Richard Weinberger 
Cc: Ryan Roberts 
Cc: Suren Baghdasaryan 
Cc: Vignesh Raghavendra 
Cc: Wei Liu 
Signed-off-by: Andrew Morton 
Stable-dep-of: f96e1d5f15b7 ("mm: avoid deadlock when holding rmap on mmap_prepare error")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

perf loongarch: Fix build failure with CONFIG_LIBDW_DWARF_UNWIND

2026-05-07T04:14:15+00:00

commit 841dbf4871c57ce2da18c4ea7ffac5487d0eda16 upstream.

Building perf for LoongArch fails when CONFIG_LIBDW_DWARF_UNWIND is
enabled because unwind-libdw.o is still referenced in
arch/loongarch/util/Build.

Fixes: e62fae9d9e8 ("perf unwind-libdw: Fix a cross-arch unwinding bug")
Signed-off-by: WANG Rui 
Acked-by: Huacai Chen 
Signed-off-by: Namhyung Kim 
Cc: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

ktest: Fix the month in the name of the failure directory

2026-05-07T04:14:13+00:00

commit 768059ede35f197575a38b10797b52402d9d4d2f upstream.

The Perl localtime() function returns the month starting at 0 not 1. This
caused the date produced to create the directory for saving files of a
failed run to have the month off by one.

  machine-test-useconfig-fail-20260314073628

The above happened in April, not March. The correct name should have been:

  machine-test-useconfig-fail-20260414073628

This was somewhat confusing.

Cc: stable@vger.kernel.org
Cc: John 'Warthog9' Hawley 
Link: https://patch.msgid.link/20260420142426.33ad0293@fedora
Fixes: 7faafbd69639b ("ktest: Add open and close console and start stop monitor")
Signed-off-by: Steven Rostedt 
Signed-off-by: Greg Kroah-Hartman

tools/accounting: handle truncated taskstats netlink messages

2026-05-07T04:13:56+00:00

commit cc82b3dcc6a8fa259fbda12ab00d6fc00908a49e upstream.

procacct and getdelays use a fixed receive buffer for taskstats generic
netlink messages.  A multi-threaded process exit can emit a single
PID+TGID notification large enough to exceed that buffer on newer kernels.

Switch to recvmsg() so MSG_TRUNC is detected explicitly, increase the
message buffer size, and report truncated datagrams clearly instead of
misparsing them as fatal netlink errors.

Also print the taskstats version in debug output to make version
mismatches easier to diagnose while inspecting taskstats traffic.

Link: https://lkml.kernel.org/r/520308bb4cbbaf8dc2c7296b5f60f11e12fb30a5.1774810498.git.cyyzero16@gmail.com
Signed-off-by: Yiyang Chen 
Cc: Balbir Singh 
Cc: Dr. Thomas Orgis 
Cc: Fan Yu 
Cc: Wang Yaxin 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

selftests/landlock: Skip stale records in audit_match_record()

2026-05-07T04:13:53+00:00

commit 07c2572a87573b2a2f0fd6b9f538cd1aeef2eee7 upstream.

Domain deallocation records are emitted asynchronously from kworker
threads (via free_ruleset_work()).  Stale deallocation records from a
previous test can arrive during the current test's deallocation read
loop and be picked up by audit_match_record() instead of the expected
record, causing a domain ID mismatch.  The audit.layers test (which
creates 16 nested domains) is particularly vulnerable because it reads
16 deallocation records in sequence, providing a large window for stale
records to interleave.

The same issue affects audit_flags.signal, where deallocation records
from a previous test (audit.layers) can leak into the next test and be
picked up by audit_match_record() instead of the expected record.

Fix this by continuing to read records when the type matches but the
content pattern does not.  Stale records are silently consumed, and the
loop only stops when both type and pattern match (or the socket times
out with -EAGAIN).

Additionally, extend matches_log_domain_deallocated() with an
expected_domain_id parameter.  When set, the regex pattern includes the
specific domain ID as a literal hex value, so that deallocation records
for a different domain do not match the pattern at all.  This handles
the case where the stale record has the same denial count as the
expected one (e.g. both have denials=1), which the type+pattern loop
alone cannot distinguish.  Callers that already know the expected domain
ID (from a prior denial or allocation record) now pass it to filter
precisely.

When expected_domain_id is set, matches_log_domain_deallocated() also
temporarily increases the socket timeout to audit_tv_dom_drop (1 second)
to wait for the asynchronous kworker deallocation, and restores
audit_tv_default afterward.  This removes the need for callers to manage
the timeout switch manually.

Cc: Günther Noack 
Cc: stable@vger.kernel.org
Fixes: 6a500b22971c ("selftests/landlock: Add tests for audit flags and domain IDs")
Link: https://lore.kernel.org/r/20260402192608.1458252-5-mic@digikod.net
Signed-off-by: Mickaël Salaün 
Signed-off-by: Greg Kroah-Hartman

selftests/landlock: Fix snprintf truncation checks in audit helpers

2026-05-07T04:13:53+00:00

commit b566f7a4f0e4f15f78f2e5fac273fa954991e03a upstream.

snprintf() returns the number of characters that would have been
written, excluding the terminating NUL byte.  When the output is
truncated, this return value equals or exceeds the buffer size.  Fix
matches_log_domain_allocated() and matches_log_domain_deallocated() to
detect truncation with ">=" instead of ">".

Cc: Günther Noack 
Cc: stable@vger.kernel.org
Fixes: 6a500b22971c ("selftests/landlock: Add tests for audit flags and domain IDs")
Reviewed-by: Günther Noack 
Link: https://lore.kernel.org/r/20260402192608.1458252-2-mic@digikod.net
Signed-off-by: Mickaël Salaün 
Signed-off-by: Greg Kroah-Hartman

selftests/landlock: Fix format warning for __u64 in net_test

2026-05-07T04:13:53+00:00

commit a060ac0b8c3345639f5f4a01e2c435d34adf7e3d upstream.

On architectures where __u64 is unsigned long (e.g. powerpc64), using
%llx to format a __u64 triggers a -Wformat warning because %llx expects
unsigned long long.  Cast the argument to unsigned long long.

Cc: Günther Noack 
Cc: stable@vger.kernel.org
Fixes: a549d055a22e ("selftests/landlock: Add network tests")
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/r/202604020206.62zgOTeP-lkp@intel.com/
Reviewed-by: Günther Noack 
Link: https://lore.kernel.org/r/20260402192608.1458252-6-mic@digikod.net
Signed-off-by: Mickaël Salaün 
Signed-off-by: Greg Kroah-Hartman

selftests/landlock: Drain stale audit records on init

2026-05-07T04:13:52+00:00

commit 3647a4977fb73da385e5a29b9775a4749733470d upstream.

Non-audit Landlock tests generate audit records as side effects when
audit_enabled is non-zero (e.g. from boot configuration).  These records
accumulate in the kernel audit backlog while no audit daemon socket is
open.  When the next test opens a new netlink socket and registers as
the audit daemon, the stale backlog is delivered, causing baseline
record count checks to fail spuriously.

Fix this by draining all pending records in audit_init() right after
setting the receive timeout.  The 1-usec SO_RCVTIMEO causes audit_recv()
to return -EAGAIN once the backlog is empty, naturally terminating the
drain loop.

Domain deallocation records are emitted asynchronously from a work
queue, so they may still arrive after the drain.  Remove records.domain
== 0 checks that are not preceded by audit_match_record() calls, which
would otherwise consume stale records before the count.  Document this
constraint above audit_count_records().

Increasing the drain timeout to catch in-flight deallocation records was
considered but rejected: a longer timeout adds latency to every
audit_init() call even when no stale record is pending, and any fixed
timeout is still not guaranteed to catch all records under load.
Removing the unprotected checks is simpler and avoids the spurious
failures.

Cc: Günther Noack 
Cc: stable@vger.kernel.org
Fixes: 6a500b22971c ("selftests/landlock: Add tests for audit flags and domain IDs")
Reviewed-by: Günther Noack 
Link: https://lore.kernel.org/r/20260402192608.1458252-4-mic@digikod.net
Signed-off-by: Mickaël Salaün 
Signed-off-by: Greg Kroah-Hartman

landlock: Allow TSYNC with LOG_SUBDOMAINS_OFF and fd=-1

2026-05-07T04:13:52+00:00

commit e75e38055b9df5eafd663c6db00e634f534dc426 upstream.

LANDLOCK_RESTRICT_SELF_TSYNC does not allow
LANDLOCK_RESTRICT_SELF_LOG_SUBDOMAINS_OFF with ruleset_fd=-1, preventing
a multithreaded process from atomically propagating subdomain log muting
to all threads without creating a domain layer.  Relax the fd=-1
condition to accept TSYNC alongside LOG_SUBDOMAINS_OFF, and update the
documentation accordingly.

Add flag validation tests for all TSYNC combinations with ruleset_fd=-1,
and audit tests verifying both transition directions: muting via TSYNC
(logged to not logged) and override via TSYNC (not logged to logged).

Cc: Günther Noack 
Cc: stable@vger.kernel.org
Fixes: 42fc7e6543f6 ("landlock: Multithreading support for landlock_restrict_self()")
Reviewed-by: Günther Noack 
Link: https://lore.kernel.org/r/20260407164107.2012589-2-mic@digikod.net
Signed-off-by: Mickaël Salaün 
Signed-off-by: Greg Kroah-Hartman

landlock: Fix LOG_SUBDOMAINS_OFF inheritance across fork()

2026-05-07T04:13:52+00:00

commit 874c8f83826c95c62c21d9edfe9ef43e5c346724 upstream.

hook_cred_transfer() only copies the Landlock security blob when the
source credential has a domain.  This is inconsistent with
landlock_restrict_self() which can set LOG_SUBDOMAINS_OFF on a
credential without creating a domain (via the ruleset_fd=-1 path): the
field is committed but not preserved across fork() because the child's
prepare_creds() calls hook_cred_transfer() which skips the copy when
domain is NULL.

This breaks the documented use case where a process mutes subdomain logs
before forking sandboxed children: the children lose the muting and
their domains produce unexpected audit records.

Fix this by unconditionally copying the Landlock credential blob.

Cc: Günther Noack 
Cc: Jann Horn 
Cc: stable@vger.kernel.org
Fixes: ead9079f7569 ("landlock: Add LANDLOCK_RESTRICT_SELF_LOG_SUBDOMAINS_OFF")
Reviewed-by: Günther Noack 
Link: https://lore.kernel.org/r/20260407164107.2012589-1-mic@digikod.net
Signed-off-by: Mickaël Salaün 
Signed-off-by: Greg Kroah-Hartman