'struct kobj_type' is not modified in this driver. It is only used with
kobject_init_and_add() which takes a "const struct kobj_type *" parameter.
Constifying this structure moves some data to a read-only section, so
increase overall security.
On a x86_64, with allmodconfig:
Before:
======
text data bss dec hex filename
22403 4184 24 26611 67f3 fs/nilfs2/sysfs.o
After:
=====
text data bss dec hex filename
22723 3928 24 26675 6833 fs/nilfs2/sysfs.o
Link: https://lkml.kernel.org/r/20240708143242.3296-1-konishi.ryusuke@gmail.com
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
According to the C standard 3.4.3p3, the result of signed integer overflow
is undefined. The macro nilfs_cnt32_ge(), which compares two sequence
numbers, uses signed integer subtraction that can overflow, and therefore
the result of the calculation may differ from what is expected due to
undefined behavior in different environments.
Similar to an earlier change to the jiffies-related comparison macros in
commit 5a581b367b ("jiffies: Avoid undefined behavior from signed
overflow"), avoid this potential issue by changing the definition of the
macro to perform the subtraction as unsigned integers, then cast the
result to a signed integer for comparison.
Link: https://lkml.kernel.org/r/20130727225828.GA11864@linux.vnet.ibm.com
Link: https://lkml.kernel.org/r/20240702183512.6390-1-konishi.ryusuke@gmail.com
Fixes: 9ff05123e3 ("nilfs2: segment constructor")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Neither ELF spec not ELF loader require program header to be placed right
after ELF header, but build-id code very much assumes such placement:
See
find_get_page(vma->vm_file->f_mapping, 0);
line and checks against PAGE_SIZE.
Returns errors for now until someone rewrites build-id parser
to be more inline with load_elf_binary().
Link: https://lkml.kernel.org/r/d58bc281-6ca7-467a-9a64-40fa214bd63e@p183
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kfifo/bytestream-example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kfifo/dma-example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kfifo/inttype-example.o
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/kfifo/record-example.o
Add the missing invocations of the MODULE_DESCRIPTION() macro.
Link: https://lkml.kernel.org/r/20240601-md-samples-kfifo-v1-1-de34345c5fd8@quicinc.com
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There were several instances of the string "assocat" in the kernel, which
should have been spelled "associat", with the various endings of -ive,
-ed, -ion, and sometimes beginnging with dis-.
Add to the spelling dictionary the corrections so that future instances
will be caught by checkpatch, and fix the instances found.
Originally noticed by accident with a 'git grep socat'.
Link: https://lkml.kernel.org/r/20240612001247.356867-1-jesse.brandeburg@intel.com
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Worst case scenario of plist_add() happens when the priority of the
inserted plist_node is going to be the largest after the insertion is
done. The cost is going to be more significant when the original plist is
longer, because the iterator is going to traverse the whole plist to find
the correct position to insert the new node.
The situation can be avoided by using a reverse iterator at the same time,
doing so the maximum possible number of iteration is going to shrink from
N to N/2.
The proposed change of plist_add pasts the test in lib/plist.c to validate
its correctness, also add the worst case scenario test for plist_add() in
plist_test().
The worst case test are tested with the size of test_data and test_node
growing from 200 to 1000. The result are showned in the following table,
in which we can observed that the proposed change of plist_add performs
better than the original version, and the difference between these two
implementations are more significant with the size of N growing.
The random case test [1], and best case test [2] are also provided, with
result showing the proposed change performs slightly better in random case
test while the original implementation performs slightly better in best
case test, while the difference in both test are minor, we can see them as
even in those two situations.
-----------------------------------------------------------
| Test size | 200 | 400 | 600 | 800 | 1000 |
-----------------------------------------------------------
| new_plist_add | 140911| 548681| 1220512| 2048493| 3763755|
-----------------------------------------------------------
| old_plist_add | 188198| 774222| 1643547| 3008929| 4947435|
-----------------------------------------------------------
Link: https://lkml.kernel.org/r/20240614154603.65203-1-richard120310@gmail.com
Signed-off-by: I Hsin Cheng <richard120310@gmail.com>
Signed-off-by: Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If hung_task_panic is enabled, don't consider the value of
hung_task_warnings and display the information of the hung tasks.
In some cases, hung_task_panic might not be initially set up, after
several hung tasks occur, the hung_task_warnings count reaches zero. If
hung_task_panic is set up later, it may not display any helpful hung task
info in dmesg, only showing messages like:
Kernel panic - not syncing: hung_task: blocked tasks
CPU: 3 PID: 58 Comm: khungtaskd Not tainted 6.10.0-rc3 #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
<TASK>
panic+0x2f3/0x320
watchdog+0x2dd/0x510
? __pfx_watchdog+0x10/0x10
kthread+0xe0/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2f/0x40
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Link: https://lkml.kernel.org/r/20240613033159.3446265-1-leonylgao@gmail.com
Signed-off-by: Yongliang Gao <leonylgao@tencent.com>
Reviewed-by: Huang Cun <cunhuang@tencent.com>
Cc: Joel Granados <j.granados@samsung.com>
Cc: John Siddle <jsiddle@redhat.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This check looks for common words that probably indicate a patch
is a fix. For now the regex is:
(?:(?:BUG: K.|UB)SAN: |Call Trace:|stable\@|syzkaller)/)
Why are stable patches encouraged to have a fixes tag? Some people mark
their stable patches as "# 5.10" etc. This is useful but a Fixes tag is
still a good idea. For example, the Fixes tag helps in review. It
helps people to not cherry-pick buggy patches without also
cherry-picking the fix.
Also if a bug affects the 5.7 kernel some people will round it up to
5.10+ because 5.7 is not supported on kernel.org. It's possible the Bad
Binder bug was caused by this sort of gap where companies outside of
kernel.org are supporting different kernels from kernel.org.
Should it be counted as a Fix when a patch just silences harmless
WARN_ON() stack trace. Yes. Definitely.
Is silencing compiler warnings a fix? It seems unfair to the original
authors, but we use -Werror now, and warnings break the build so let's
just add Fixes tags. I tell people that silencing static checker
warnings is not a fix but the rules on this vary by subsystem.
Is fixing a minor LTP issue (Linux Test Project) a fix? Probably? It's
hard to know what to do if the LTP test has technically always been
broken.
One clear false positive from this check is when someone updated their
debug output and included before and after Call Traces. Or when crashes
are introduced deliberately for testing. In those cases, you should
just ignore checkpatch.
Link: https://lkml.kernel.org/r/ZmhUgZBKeF_8ixA6@moroto
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Thorsten Leemhuis <linux@leemhuis.info>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Call mark_buffer_dirty() for segment summary and super root block buffers
on the backing device's page cache, thereby indirectly calling
inode_attach_wb().
Then remove the no longer needed call to inode_attach_wb() in
nilfs_attach_log_writer(), resolving the concern about its layer-violating
use.
Link: https://lkml.kernel.org/r/20240610160029.7673-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "nilfs2: eliminate the call to inode_attach_wb()".
This series eliminates the inode_attach_wb() call from nilfs2, which was
introduced as a workaround for a kernel bug but is suspected of layer
violation (in fact, it is undesirable since it exposes a reference to the
backing device).
Removal of the inode_attach_wb() call is done by simply using
mark_buffer_dirty() on the backing device's buffers. To use it safely,
this series will prepare it in patch 1/2, and perform the replacement
itself in patch 2/2.
This patch (of 2):
In preparation for inode_attach_wb(), which is currently called when
attaching the log writer, to be done via mark_buffer_dirty(), change the
order of preparation for log writing.
Specifically, the function call that adds checksums to segment summary and
super root blocks, which correspond to the log header and trailer, is made
before starting writeback of folios containing those blocks.
The current steps are as follows:
1. Put the folios of segment summary blocks in writeback state.
2. Put the folios of data blocks, metadata file blocks, and btree node
blocks (collectively called payload blocks) into writeback state.
3. Put the super root block folio in writeback state.
4. Add checksums.
Change these as follows:
1. Put the folios of payload blocks in writeback state.
2. Add checksums.
3. Put the folios of segment summary blocks in writeback state.
4. Put the super root block folio in writeback state.
In this order, the contents of segment summaries and super root block
that directly use buffer/folio of the backing device can be determined
including the addition of checksums, before preparing to write.
Step (1), which puts the payload block folios in writeback state, is
performed first because if there are memory-mapped data blocks, a valid
checksum can only be calculated after step (1).
Link: https://lkml.kernel.org/r/20240610160029.7673-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
make allmodconfig && make W=1 C=1 reports for lib/*kunit:
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/bitfield_kunit.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/checksum_kunit.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/cmdline_kunit.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/is_signed_type_kunit.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/overflow_kunit.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/stackinit_kunit.o
Add the missing invocations of the MODULE_DESCRIPTION() macro.
Link: https://lkml.kernel.org/r/20240601-md-lib-kunit-tests-v1-1-4493fe0032b9@quicinc.com
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
