Age | Commit message (Collapse) | Author |
|
Use the helper function rather than reading it directly.
Reviewed-by: Yang Wang <kevinyang.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 0ec43fbece784215d3c4469973e4556d70bce915)
Cc: stable@vger.kernel.org
|
|
This helps to avoid a spurious PME event on hotplug to Azalia.
Cc: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Reported-and-tested-by: ionut_n2001@yahoo.com
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=215884
Tested-by: Gabriel Marcano <gabemarcano@yahoo.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://lore.kernel.org/r/20241211024414.7840-1-mario.limonciello@amd.com
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 3f6f237b9dd189e1fb85b8a3f7c97a8f27c1e49a)
Cc: stable@vger.kernel.org
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull selinux fix from Paul Moore:
"One small SELinux patch to get rid improve our handling of unknown
extended permissions by safely ignoring them.
Not only does this make it easier to support newer SELinux policy
on older kernels in the future, it removes to BUG() calls from the
SELinux code."
* tag 'selinux-pr-20241217' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: ignore unknown extended permissions
|
|
Commit a6021aa24f6417416d933 ("ACPI: EC: make EC support compile-time
conditional") only enable ACPI_EC on X86 by default, but the embedded
controller is also widely used on LoongArch laptops so we also enable
ACPI_EC for LoongArch.
The laptop driver cannot work without EC, so also update the dependency
of LOONGSON_LAPTOP to let it depend on APCI_EC.
Fixes: a6021aa24f6417416d933 ("ACPI: EC: make EC support compile-time conditional")
Reported-by: Xiaotian Wu <wuxiaotian@loongson.cn>
Tested-by: Binbin Zhou <zhoubinbin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Link: https://patch.msgid.link/20241217073704.3339587-1-chenhuacai@loongson.cn
[ rjw: Added Fixes: ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
|
The TP_printk() of a TRACE_EVENT() is a generic printf format that any
developer can create for their event. It may include pointers to strings
and such. A boot mapped buffer may contain data from a previous kernel
where the strings addresses are different.
One solution is to copy the event content and update the pointers by the
recorded delta, but a simpler solution (for now) is to just use the
print_fields() function to print these events. The print_fields() function
just iterates the fields and prints them according to what type they are,
and ignores the TP_printk() format from the event itself.
To understand the difference, when printing via TP_printk() the output
looks like this:
4582.696626: kmem_cache_alloc: call_site=getname_flags+0x47/0x1f0 ptr=00000000e70e10e0 bytes_req=4096 bytes_alloc=4096 gfp_flags=GFP_KERNEL node=-1 accounted=false
4582.696629: kmem_cache_alloc: call_site=alloc_empty_file+0x6b/0x110 ptr=0000000095808002 bytes_req=360 bytes_alloc=384 gfp_flags=GFP_KERNEL node=-1 accounted=false
4582.696630: kmem_cache_alloc: call_site=security_file_alloc+0x24/0x100 ptr=00000000576339c3 bytes_req=16 bytes_alloc=16 gfp_flags=GFP_KERNEL|__GFP_ZERO node=-1 accounted=false
4582.696653: kmem_cache_free: call_site=do_sys_openat2+0xa7/0xd0 ptr=00000000e70e10e0 name=names_cache
But when printing via print_fields() (echo 1 > /sys/kernel/tracing/options/fields)
the same event output looks like this:
4582.696626: kmem_cache_alloc: call_site=0xffffffff92d10d97 (-1831793257) ptr=0xffff9e0e8571e000 (-107689771147264) bytes_req=0x1000 (4096) bytes_alloc=0x1000 (4096) gfp_flags=0xcc0 (3264) node=0xffffffff (-1) accounted=(0)
4582.696629: kmem_cache_alloc: call_site=0xffffffff92d0250b (-1831852789) ptr=0xffff9e0e8577f800 (-107689770747904) bytes_req=0x168 (360) bytes_alloc=0x180 (384) gfp_flags=0xcc0 (3264) node=0xffffffff (-1) accounted=(0)
4582.696630: kmem_cache_alloc: call_site=0xffffffff92efca74 (-1829778828) ptr=0xffff9e0e8d35d3b0 (-107689640864848) bytes_req=0x10 (16) bytes_alloc=0x10 (16) gfp_flags=0xdc0 (3520) node=0xffffffff (-1) accounted=(0)
4582.696653: kmem_cache_free: call_site=0xffffffff92cfbea7 (-1831879001) ptr=0xffff9e0e8571e000 (-107689771147264) name=names_cache
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20241218141507.28389a1d@gandalf.local.home
Fixes: 07714b4bb3f98 ("tracing: Handle old buffer mappings for event strings and functions")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
An overflow occurred when performing the following calculation:
nr_pages = ((nr_subbufs + 1) << subbuf_order) - pgoff;
Add a check before the calculation to avoid this problem.
syzbot reported this as a slab-out-of-bounds in __rb_map_vma:
BUG: KASAN: slab-out-of-bounds in __rb_map_vma+0x9ab/0xae0 kernel/trace/ring_buffer.c:7058
Read of size 8 at addr ffff8880767dd2b8 by task syz-executor187/5836
CPU: 0 UID: 0 PID: 5836 Comm: syz-executor187 Not tainted 6.13.0-rc2-syzkaller-00159-gf932fb9b4074 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xc3/0x620 mm/kasan/report.c:489
kasan_report+0xd9/0x110 mm/kasan/report.c:602
__rb_map_vma+0x9ab/0xae0 kernel/trace/ring_buffer.c:7058
ring_buffer_map+0x56e/0x9b0 kernel/trace/ring_buffer.c:7138
tracing_buffers_mmap+0xa6/0x120 kernel/trace/trace.c:8482
call_mmap include/linux/fs.h:2183 [inline]
mmap_file mm/internal.h:124 [inline]
__mmap_new_file_vma mm/vma.c:2291 [inline]
__mmap_new_vma mm/vma.c:2355 [inline]
__mmap_region+0x1786/0x2670 mm/vma.c:2456
mmap_region+0x127/0x320 mm/mmap.c:1348
do_mmap+0xc00/0xfc0 mm/mmap.c:496
vm_mmap_pgoff+0x1ba/0x360 mm/util.c:580
ksys_mmap_pgoff+0x32c/0x5c0 mm/mmap.c:542
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The reproducer for this bug is:
------------------------8<-------------------------
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <asm/types.h>
#include <sys/mman.h>
int main(int argc, char **argv)
{
int page_size = getpagesize();
int fd;
void *meta;
system("echo 1 > /sys/kernel/tracing/buffer_size_kb");
fd = open("/sys/kernel/tracing/per_cpu/cpu0/trace_pipe_raw", O_RDONLY);
meta = mmap(NULL, page_size, PROT_READ, MAP_SHARED, fd, page_size * 5);
}
------------------------>8-------------------------
Cc: stable@vger.kernel.org
Fixes: 117c39200d9d7 ("ring-buffer: Introducing ring-buffer mapping functions")
Link: https://lore.kernel.org/tencent_06924B6674ED771167C23CC336C097223609@qq.com
Reported-by: syzbot+345e4443a21200874b18@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=345e4443a21200874b18
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull tracing fixes from Steven Rostedt:
"Replace trace_check_vprintf() with test_event_printk() and
ignore_event()
The function test_event_printk() checks on boot up if the trace event
printf() formats dereference any pointers, and if they do, it then
looks at the arguments to make sure that the pointers they dereference
will exist in the event on the ring buffer. If they do not, it issues
a WARN_ON() as it is a likely bug.
But this isn't the case for the strings that can be dereferenced with
"%s", as some trace events (notably RCU and some IPI events) save a
pointer to a static string in the ring buffer. As the string it points
to lives as long as the kernel is running, it is not a bug to
reference it, as it is guaranteed to be there when the event is read.
But it is also possible (and a common bug) to point to some allocated
string that could be freed before the trace event is read and the
dereference is to bad memory. This case requires a run time check.
The previous way to handle this was with trace_check_vprintf() that
would process the printf format piece by piece and send what it didn't
care about to vsnprintf() to handle arguments that were not strings.
This kept it from having to reimplement vsnprintf(). But it relied on
va_list implementation and for architectures that copied the va_list
and did not pass it by reference, it wasn't even possible to do this
check and it would be skipped. As 64bit x86 passed va_list by
reference, most events were tested and this kept out bugs where
strings would have been dereferenced after being freed.
Instead of relying on the implementation of va_list, extend the boot
up test_event_printk() function to validate all the "%s" strings that
can be validated at boot, and for the few events that point to strings
outside the ring buffer, flag both the event and the field that is
dereferenced as "needs_test". Then before the event is printed, a call
to ignore_event() is made, and if the event has the flag set, it
iterates all its fields and for every field that is to be tested, it
will read the pointer directly from the event in the ring buffer and
make sure that it is valid. If the pointer is not valid, it will print
a WARN_ON(), print out to the trace that the event has unsafe memory
and ignore the print format.
With this new update, the trace_check_vprintf() can be safely removed
and now all events can be verified regardless of architecture"
* tag 'trace-v6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Check "%s" dereference via the field and not the TP_printk format
tracing: Add "%s" check in test_event_printk()
tracing: Add missing helper functions in event pointer dereference check
tracing: Fix test_event_printk() to process entire print argument
|
|
Third time's the charm, I hope?
Fixes: d3116756a710 ("drm/ttm: rename bo->mem and make it a pointer")
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3837
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Michel Dänzer <mdaenzer@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 695c2c745e5dff201b75da8a1d237ce403600d04)
Cc: stable@vger.kernel.org
|
|
The VM pointer might already be outdated when that function is called.
Use the PASID instead to gather the information instead.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 57f812d171af4ba233d3ed7c94dfa5b8e92dcc04)
Cc: stable@vger.kernel.org
|
|
Use the helper function rather than reading it directly.
Reviewed-by: Yang Wang <kevinyang.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 8f2cd1067afe68372a1723e05e19b68ed187676a)
Cc: stable@vger.kernel.org
|
|
Use the helper function rather than reading it directly.
Reviewed-by: Yang Wang <kevinyang.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit f1fd1d0f40272948aa6ab82a3a82ecbbc76dff53)
Cc: stable@vger.kernel.org
|
|
Use the helper function rather than reading it directly.
Reviewed-by: Yang Wang <kevinyang.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 63bfd24088b42c6f55c2096bfc41b50213d419b2)
Cc: stable@vger.kernel.org
|
|
Use the helper function rather than reading it directly.
Reviewed-by: Yang Wang <kevinyang.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 2c8eeaaa0fe5841ccf07a0eb51b1426f34ef39f7)
Cc: stable@vger.kernel.org
|
|
Use the helper function rather than reading it directly.
Reviewed-by: Yang Wang <kevinyang.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 22b9555bc90df22b585bdd1f161b61584b13af51)
Cc: stable@vger.kernel.org
|
|
Since 2320c9e6a768 ("drm/sched: memset() 'job' in drm_sched_job_init()")
accessing job->base.sched can produce unexpected results as the initialisation
of (*job)->base.sched done in amdgpu_job_alloc is overwritten by the
memset.
This commit fixes an issue when a CS would fail validation and would
be rejected after job->num_ibs is incremented. In this case,
amdgpu_ib_free(ring->adev, ...) will be called, which would crash the
machine because the ring value is bogus.
To fix this, pass a NULL pointer to amdgpu_ib_free(): we can do this
because the device is actually not used in this function.
The next commit will remove the ring argument completely.
Fixes: 2320c9e6a768 ("drm/sched: memset() 'job' in drm_sched_job_init()")
Signed-off-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 2ae520cb12831d264ceb97c61f72c59d33c0dbd7)
|
|
If the kernel hasn't been compiled with PCIe hotplug support this
can lead to problems with dGPUs that use BOCO because they effectively
drop off the bus.
To prevent issues, disable BOCO support when compiled without PCIe hotplug.
Reported-by: Gabriel Marcano <gabemarcano@yahoo.com>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/1707#note_2696862
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://lore.kernel.org/r/20241211155601.3585256-1-superm1@kernel.org
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 1ad5bdc28bafa66db0f041cc6cdd278a80426aae)
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux
Pull hyperv fixes from Wei Liu:
- Various fixes to Hyper-V tools in the kernel tree (Dexuan Cui, Olaf
Hering, Vitaly Kuznetsov)
- Fix a bug in the Hyper-V TSC page based sched_clock() (Naman Jain)
- Two bug fixes in the Hyper-V utility functions (Michael Kelley)
- Convert open-coded timeouts to secs_to_jiffies() in Hyper-V drivers
(Easwar Hariharan)
* tag 'hyperv-fixes-signed-20241217' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
tools/hv: reduce resource usage in hv_kvp_daemon
tools/hv: add a .gitignore file
tools/hv: reduce resouce usage in hv_get_dns_info helper
hv/hv_kvp_daemon: Pass NIC name to hv_get_dns_info as well
Drivers: hv: util: Avoid accessing a ringbuffer not initialized yet
Drivers: hv: util: Don't force error code to ENODEV in util_probe()
tools/hv: terminate fcopy daemon if read from uio fails
drivers: hv: Convert open-coded timeouts to secs_to_jiffies()
tools: hv: change permissions of NetworkManager configuration file
x86/hyperv: Fix hv tsc page based sched_clock for hibernation
tools: hv: Fix a complier warning in the fcopy uio daemon
|
|
In 32-bit x86 builds CONFIG_STATIC_CALL_INLINE isn't set, leading to
static_call_initialized not being available.
Define it as "0" in that case.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 0ef8047b737d ("x86/static-call: provide a way to do very early static-call updates")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Fix error in remove progress:
[ 43.026148] Call trace:
[ 43.026370] klist_next+0x1c/0x1d4
[ 43.026671] device_for_each_child+0x48/0xac
[ 43.027049] spi_unregister_controller+0x30/0x130
[ 43.027469] rockchip_sfc_remove+0x48/0x80 [spi_rockchip_sfc]
Signed-off-by: Jon Lin <jon.lin@rock-chips.com>
Link: https://patch.msgid.link/20241218154741.901591-1-jon.lin@rock-chips.com
Signed-off-by: Mark Brown <broonie@kernel.org>
|
|
ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/superm1/linux
Merge amd-pstate driver fixes for 6.13-rc4 from Mario Liminciello:
"Fix a problem where systems without preferred cores were
misdetecting preferred cores.
Fix issues with with boost numerator handling leading to
inconsistently programmed CPPC max performance values."
* tag 'amd-pstate-v6.13-2024-12-11' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/superm1/linux:
cpufreq/amd-pstate: Use boost numerator for upper bound of frequencies
cpufreq/amd-pstate: Store the boost numerator as highest perf again
cpufreq/amd-pstate: Detect preferred core support before driver registration
|
|
If the 'hctx' isn't removed from cpuhp callback list, we can't reuse it,
otherwise use-after-free may be triggered.
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202412172217.b906db7c-lkp@intel.com
Tested-by: kernel test robot <oliver.sang@intel.com>
Fixes: 22465bbac53c ("blk-mq: move cpuhp callback registering out of q->sysfs_lock")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241218101617.3275704-3-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
acquiring sysfs_lock"
This reverts commit be26ba96421ab0a8fa2055ccf7db7832a13c44d2.
Commit be26ba96421a ("block: Fix potential deadlock while freezing queue and
acquiring sysfs_loc") actually reverts commit 22465bbac53c ("blk-mq: move cpuhp
callback registering out of q->sysfs_lock"), and causes the original resctrl
lockdep warning.
So revert it and we need to fix the issue in another way.
Cc: Nilay Shroff <nilay@linux.ibm.com>
Fixes: be26ba96421a ("block: Fix potential deadlock while freezing queue and acquiring sysfs_loc")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241218101617.3275704-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
The block layer already has support to validates proper block sizes
with blk_validate_block_size(), we can leverage that as well.
No functional changes.
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241218020212.3657139-3-mcgrof@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
We already have a helper for checking the limits on the block size
both low and high, just use that.
No functional changes.
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241218020212.3657139-2-mcgrof@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
|
|
The calibration procedure needs some time to finish.
This patch adds the delay time to ensure the calibration procedure is completed correctly.
Signed-off-by: Shuming Fan <shumingf@realtek.com>
Link: https://patch.msgid.link/20241218091307.96656-1-shumingf@realtek.com
Signed-off-by: Mark Brown <broonie@kernel.org>
|
|
The current implementation does not work if the thermal zone is
interrupt driven only.
The boundaries are not correctly checked and computed as it happens
only when the temperature is increasing or decreasing.
The problem arises because the routine to detect when we cross a
threshold is correlated with the computation of the boundaries. We
assume we have to recompute the boundaries when a threshold is crossed
but actually we should do that even if the it is not the case.
Mixing the boundaries computation and the threshold detection for the
sake of optimizing the routine is much more complex as it appears
intuitively and prone to errors.
This fix separates the boundaries computation and the threshold
crossing detection into different routines. The result is a code much
more simple to understand, thus easier to maintain.
The drawback is we browse the thresholds list several time but we can
consider that as neglictible because that happens when the temperature
is updated. There are certainly some aeras to improve in the
temperature update routine but it would be not adequate as this change
aims to fix the thresholds for v6.13.
Fixes: 445936f9e258 ("thermal: core: Add user thresholds support")
Tested-by: Daniel Lezcano <daniel.lezcano@linaro.org> # rock5b, Lenovo x13s
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://patch.msgid.link/20241216212644.1145122-1-daniel.lezcano@linaro.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
|
When the timer supports complementary output, the CCxNE bit must be set
additionally to the CCxE bit. So to not overwrite the latter use |=
instead of = to set the former.
Fixes: deaba9cff809 ("pwm: stm32: Implementation of the waveform callbacks")
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20241217150021.2030213-1-fabrice.gasnier@foss.st.com
[ukleinek: Slightly improve commit log]
Signed-off-by: Uwe Kleine-König <ukleinek@kernel.org>
|
|
This series fixes problems in the m_can_pci driver found on the Intel
Elkhart Lake processor.
Link: https://patch.msgid.link/e247f331cb72829fcbdfda74f31a59cbad1a6006.1728288535.git.matthias.schiffer@ew.tq-group.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
|
|
The interrupt line of PCI devices is interpreted as edge-triggered,
however the interrupt signal of the m_can controller integrated in Intel
Elkhart Lake CPUs appears to be generated level-triggered.
Consider the following sequence of events:
- IR register is read, interrupt X is set
- A new interrupt Y is triggered in the m_can controller
- IR register is written to acknowledge interrupt X. Y remains set in IR
As at no point in this sequence no interrupt flag is set in IR, the
m_can interrupt line will never become deasserted, and no edge will ever
be observed to trigger another run of the ISR. This was observed to
result in the TX queue of the EHL m_can to get stuck under high load,
because frames were queued to the hardware in m_can_start_xmit(), but
m_can_finish_tx() was never run to account for their successful
transmission.
On an Elkhart Lake based board with the two CAN interfaces connected to
each other, the following script can reproduce the issue:
ip link set can0 up type can bitrate 1000000
ip link set can1 up type can bitrate 1000000
cangen can0 -g 2 -I 000 -L 8 &
cangen can0 -g 2 -I 001 -L 8 &
cangen can0 -g 2 -I 002 -L 8 &
cangen can0 -g 2 -I 003 -L 8 &
cangen can0 -g 2 -I 004 -L 8 &
cangen can0 -g 2 -I 005 -L 8 &
cangen can0 -g 2 -I 006 -L 8 &
cangen can0 -g 2 -I 007 -L 8 &
cangen can1 -g 2 -I 100 -L 8 &
cangen can1 -g 2 -I 101 -L 8 &
cangen can1 -g 2 -I 102 -L 8 &
cangen can1 -g 2 -I 103 -L 8 &
cangen can1 -g 2 -I 104 -L 8 &
cangen can1 -g 2 -I 105 -L 8 &
cangen can1 -g 2 -I 106 -L 8 &
cangen can1 -g 2 -I 107 -L 8 &
stress-ng --matrix 0 &
To fix the issue, repeatedly read and acknowledge interrupts at the
start of the ISR until no interrupt flags are set, so the next incoming
interrupt will also result in an edge on the interrupt line.
While we have received a report that even with this patch, the TX queue
can become stuck under certain (currently unknown) circumstances on the
Elkhart Lake, this patch completely fixes the issue with the above
reproducer, and it is unclear whether the remaining issue has a similar
cause at all.
Fixes: cab7ffc0324f ("can: m_can: add PCI glue driver for Intel Elkhart Lake")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reviewed-by: Markus Schneider-Pargmann <msp@baylibre.com>
Link: https://patch.msgid.link/fdf0439c51bcb3a46c21e9fb21c7f1d06363be84.1728288535.git.matthias.schiffer@ew.tq-group.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
|
|
While an m_can controller usually already has the init flag from a
hardware reset, no such reset happens on the integrated m_can_pci of the
Intel Elkhart Lake. If the CAN controller is found in an active state,
m_can_dev_setup() would fail because m_can_niso_supported() calls
m_can_cccr_update_bits(), which refuses to modify any other configuration
bits when CCCR_INIT is not set.
To avoid this issue, set CCCR_INIT before attempting to modify any other
configuration flags.
Fixes: cd5a46ce6fa6 ("can: m_can: don't enable transceiver when probing")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Reviewed-by: Markus Schneider-Pargmann <msp@baylibre.com>
Link: https://patch.msgid.link/e247f331cb72829fcbdfda74f31a59cbad1a6006.1728288535.git.matthias.schiffer@ew.tq-group.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
|
|
Xiao Liang reported that the cited commit changed netns handling
in newlink() of netkit, veth, and vxcan.
Before the patch, if we don't find a netns attribute in the peer
device attributes, we tried to find another netns attribute in
the outer netlink attributes by passing it to rtnl_link_get_net().
Let's restore the original behaviour.
Fixes: 48327566769a ("rtnetlink: fix double call of rtnl_link_get_net_ifla()")
Reported-by: Xiao Liang <shaw.leon@gmail.com>
Closes: https://lore.kernel.org/netdev/CABAhCORBVVU8P6AHcEkENMj+gD2d3ce9t=A_o48E0yOQp8_wUQ@mail.gmail.com/#t
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Xiao Liang <shaw.leon@gmail.com>
Link: https://patch.msgid.link/20241216110432.51488-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
nsim_pp_hold_write() has two problems:
1) It may return with rtnl held, as found by syzbot.
2) Its return value does not propagate an error if any.
Fixes: 1580cbcbfe77 ("net: netdevsim: add some fake page pool use")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20241216083703.1859921-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
On x86-64 calling bpf_get_smp_processor_id() in a kernel with CONFIG_SMP
disabled can trigger the following bug, as pcpu_hot is unavailable:
[ 8.471774] BUG: unable to handle page fault for address: 00000000936a290c
[ 8.471849] #PF: supervisor read access in kernel mode
[ 8.471881] #PF: error_code(0x0000) - not-present page
Fix by inlining a return 0 in the !CONFIG_SMP case.
Fixes: 1ae6921009e5 ("bpf: inline bpf_get_smp_processor_id() helper")
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20241217195813.622568-1-arighi@nvidia.com
|
|
The Hexagon-specific constant extender optimization in LLVM may crash on
Linux kernel code [1], such as fs/bcache/btree_io.c after
commit 32ed4a620c54 ("bcachefs: Btree path tracepoints") in 6.12:
clang: llvm/lib/Target/Hexagon/HexagonConstExtenders.cpp:745: bool (anonymous namespace)::HexagonConstExtenders::ExtRoot::operator<(const HCE::ExtRoot &) const: Assertion `ThisB->getParent() == OtherB->getParent()' failed.
Stack dump:
0. Program arguments: clang --target=hexagon-linux-musl ... fs/bcachefs/btree_io.c
1. <eof> parser at end of file
2. Code generation
3. Running pass 'Function Pass Manager' on module 'fs/bcachefs/btree_io.c'.
4. Running pass 'Hexagon constant-extender optimization' on function '@__btree_node_lock_nopath'
Without assertions enabled, there is just a hang during compilation.
This has been resolved in LLVM main (20.0.0) [2] and backported to LLVM
19.1.0 but the kernel supports LLVM 13.0.1 and newer, so disable the
constant expander optimization using the '-mllvm' option when using a
toolchain that is not fixed.
Cc: stable@vger.kernel.org
Link: https://github.com/llvm/llvm-project/issues/99714 [1]
Link: https://github.com/llvm/llvm-project/commit/68df06a0b2998765cb0a41353fcf0919bbf57ddb [2]
Link: https://github.com/llvm/llvm-project/commit/2ab8d93061581edad3501561722ebd5632d73892 [3]
Reviewed-by: Brian Cain <bcain@quicinc.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
There is a race condition between exiting wb_on_itr and completion write
backs. For example, we are in wb_on_itr mode and a Tx completion is
generated by HW, ready to be written back, as we are re-enabling
interrupts:
HW SW
| |
| | idpf_tx_splitq_clean_all
| | napi_complete_done
| |
| tx_completion_wb | idpf_vport_intr_update_itr_ena_irq
That tx_completion_wb happens before the vector is fully re-enabled.
Continuing with this example, it is a UDP stream and the
tx_completion_wb is the last one in the flow (there are no rx packets).
Because the HW generated the completion before the interrupt is fully
enabled, the HW will not fire the interrupt once the timer expires and
the write back will not happen. NAPI poll won't be called. We have
indicated we're back in interrupt mode but nothing else will trigger the
interrupt. Therefore, the completion goes unprocessed, triggering a Tx
timeout.
To mitigate this, fire a SW triggered interrupt upon exiting wb_on_itr.
This interrupt will catch the rogue completion and avoid the timeout.
Add logic to set the appropriate bits in the vector's dyn_ctl register.
Fixes: 9c4a27da0ecc ("idpf: enable WB_ON_ITR")
Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
Signed-off-by: Joshua Hay <joshua.a.hay@intel.com>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
|
|
Currently the pending_async_copies count is decremented just
before a struct nfsd4_copy is destroyed. After commit aa0ebd21df9c
("NFSD: Add nfsd4_copy time-to-live") nfsd4_copy structures sticks
around for 10 lease periods after the COPY itself has completed,
the pending_async_copies count stays high for a long time. This
causes NFSD to avoid the use of background copy even though the
actual background copy workload might no longer be running.
In this patch, decrement pending_async_copies once async copy thread
is done processing the copy work.
Fixes: aa0ebd21df9c ("NFSD: Add nfsd4_copy time-to-live")
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
|
|
SW triggered interrupts are guaranteed to fire after their timer
expires, unlike Tx and Rx interrupts which will only fire after the
timer expires _and_ a descriptor write back is available to be processed
by the driver.
Add the necessary fields, defines, and initializations to enable a SW
triggered interrupt in the vector's dyn_ctl register.
Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
Signed-off-by: Joshua Hay <joshua.a.hay@intel.com>
Tested-by: Krishneil Singh <krishneil.k.singh@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
|
|
Set the cache-line-size parameter of the L2 cache for each core to the
correct value of 64 bytes.
Previously, the L2 cache line size was incorrectly set to 128 bytes
for the Broadcom BCM2712. This causes validation tests for the
Performance Application Programming Interface (PAPI) tool to fail as
they depend on sysfs accurately reporting cache line sizes.
The correct value of 64 bytes is stated in the official documentation of
the ARM Cortex A-72, which is linked in the comments of
arm64/boot/dts/broadcom/bcm2712.dtsi as the source for cache-line-size.
Fixes: faa3381267d0 ("arm64: dts: broadcom: Add minimal support for Raspberry Pi 5")
Signed-off-by: Willow Cunningham <willow.e.cunningham@maine.edu>
Link: https://lore.kernel.org/r/20241007212954.214724-1-willow.e.cunningham@maine.edu
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
|
|
[BUG]
There is a bug report in the mailing list where btrfs_run_delayed_refs()
failed to drop the ref count for logical 25870311358464 num_bytes
2113536.
The involved leaf dump looks like this:
item 166 key (25870311358464 168 2113536) itemoff 10091 itemsize 50
extent refs 1 gen 84178 flags 1
ref#0: shared data backref parent 32399126528000 count 0 <<<
ref#1: shared data backref parent 31808973717504 count 1
Notice the count number is 0.
[CAUSE]
There is no concrete evidence yet, but considering 0 -> 1 is also a
single bit flipped, it's possible that hardware memory bitflip is
involved, causing the on-disk extent tree to be corrupted.
[FIX]
To prevent us reading such corrupted extent item, or writing such
damaged extent item back to disk, enhance the handling of
BTRFS_EXTENT_DATA_REF_KEY and BTRFS_SHARED_DATA_REF_KEY keys for both
inlined and key items, to detect such 0 ref count and reject them.
CC: stable@vger.kernel.org # 5.4+
Link: https://lore.kernel.org/linux-btrfs/7c69dd49-c346-4806-86e7-e6f863a66f48@app.fastmail.com/
Reported-by: Frankie Fisher <frankie@terrorise.me.uk>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Btrfs like other file systems can't really deal with I/O not aligned to
it's internal block size (which strangely is called sector size in
btrfs, for historical reasons), but the block layer split helper doesn't
even know about that.
Round down the split boundary so that all I/Os are aligned.
Fixes: d5e4377d5051 ("btrfs: split zone append bios in btrfs_submit_bio")
CC: stable@vger.kernel.org # 6.12
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Otherwise it won't catch bios turned into regular writes by the block
level zone write plugging. The additional test it adds is for emulated
zone append.
Fixes: 9b1ce7f0c6f8 ("block: Implement zone append emulation")
CC: stable@vger.kernel.org # 6.12
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
We have been using the following check
if (generation <= root->root_key.offset)
to make decisions about whether or not to visit a node during snapshot
delete. This is because for normal subvolumes this is set to 0, and for
snapshots it's set to the creation generation. The idea being that if
the generation of the node is less than or equal to our creation
generation then we don't need to visit that node, because it doesn't
belong to us, we can simply drop our reference and move on.
However reloc roots don't have their generation stored in
root->root_key.offset, instead that is the objectid of their
corresponding fs root. This means we can incorrectly not walk into
nodes that need to be dropped when deleting a reloc root.
There are a variety of consequences to making the wrong choice in two
distinct areas.
visit_node_for_delete()
1. False positive. We think we are newer than the block when we really
aren't. We don't visit the node and drop our reference to the node
and carry on. This would result in leaked space.
2. False negative. We do decide to walk down into a block that we
should have just dropped our reference to. However this means that
the child node will have refs > 1, so we will switch to
UPDATE_BACKREF, and then the subsequent walk_down_proc() will notice
that btrfs_header_owner(node) != root->root_key.objectid and it'll
break out of the loop, and then walk_up_proc() will drop our reference,
so this appears to be ok.
do_walk_down()
1. False positive. We are in UPDATE_BACKREF and incorrectly decide that
we are done and don't need to update the backref for our lower nodes.
This is another case that simply won't happen with relocation, as we
only have to do UPDATE_BACKREF if the node below us was shared and
didn't have FULL_BACKREF set, and since we don't own that node
because we're a reloc root we actually won't end up in this case.
2. False negative. Again this is tricky because as described above, we
simply wouldn't be here from relocation, because we don't own any of
the nodes because we never set btrfs_header_owner() to the reloc root
objectid, and we always use FULL_BACKREF, we never actually need to
set FULL_BACKREF on any children.
Having spent a lot of time stressing relocation/snapshot delete recently
I've not seen this pop in practice. But this is objectively incorrect,
so fix this to get the correct starting generation based on the root
we're dropping to keep me from thinking there's a problem here.
CC: stable@vger.kernel.org
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
The 'select FB_CORE' statement moved from CONFIG_DRM to DRM_CLIENT_LIB,
but there are now configurations that have code calling into fb_core
as built-in even though the client_lib itself is a loadable module:
x86_64-linux-ld: drivers/gpu/drm/drm_fb_helper.o: in function `drm_fb_helper_set_suspend':
drm_fb_helper.c:(.text+0x2c6): undefined reference to `fb_set_suspend'
x86_64-linux-ld: drivers/gpu/drm/drm_fb_helper.o: in function `drm_fb_helper_resume_worker':
drm_fb_helper.c:(.text+0x2e1): undefined reference to `fb_set_suspend'
In addition to DRM_CLIENT_LIB, the 'select' needs to be at least in
DRM_KMS_HELPER and DRM_GEM_SHMEM_HELPER, so add it here.
This patch is the KMS_HELPER part of [1].
Fixes: dadd28d4142f ("drm/client: Add client-lib module")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/series/141411/ # 1
Link: https://patchwork.freedesktop.org/patch/msgid/20241216074450.8590-4-tzimmermann@suse.de
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ftrace fixes from Steven Rostedt:
- Always try to initialize the idle functions when graph tracer starts
A bug was found that when a CPU is offline when graph tracing starts
and then comes online, that CPU is not traced. The fix to that was to
move the initialization of the idle shadow stack over to the hot plug
online logic, which also handle onlined CPUs. The issue was that it
removed the initialization of the shadow stack when graph tracing
starts, but the callbacks to the hot plug logic do nothing if graph
tracing isn't currently running. Although that fix fixed the onlining
of a CPU during tracing, it broke the CPUs that were already online.
- Have microblaze not try to get the "true parent" in function tracing
If function tracing and graph tracing are both enabled at the same
time the parent of the functions traced by the function tracer may
sometimes be the graph tracing trampoline. The graph tracing hijacks
the return pointer of the function to trace it, but that can
interfere with the function tracing parent output.
This was fixed by using the ftrace_graph_ret_addr() function passing
in the kernel stack pointer using the ftrace_regs_get_stack_pointer()
function. But Al Viro reported that Microblaze does not implement the
kernel_stack_pointer(regs) helper function that
ftrace_regs_get_stack_pointer() uses and fails to compile when
function graph tracing is enabled.
It was first thought that this was a microblaze issue, but the real
cause is that this only works when an architecture implements
HAVE_DYNAMIC_FTRACE_WITH_ARGS, as a requirement for that config is to
have ftrace always pass a valid ftrace_regs to the callbacks. That
also means that the architecture supports
ftrace_regs_get_stack_pointer()
Microblaze does not set HAVE_DYNAMIC_FTRACE_WITH_ARGS nor does it
implement ftrace_regs_get_stack_pointer() which caused it to fail to
build. Only implement the "true parent" logic if an architecture has
that config set"
* tag 'ftrace-v6.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ftrace: Do not find "true_parent" if HAVE_DYNAMIC_FTRACE_WITH_ARGS is not set
fgraph: Still initialize idle shadow stacks when starting
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Alexander Gordeev:
- Fix DirectMap accounting in /proc/meminfo file
- Fix strscpy() return code handling that led to "unsigned 'len' is
never less than zero" warning
- Fix the calculation determining whether to use three- or four-level
paging: account KMSAN modules metadata
* tag 's390-6.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/mm: Consider KMSAN modules metadata for paging levels
s390/ipl: Fix never less than zero warning
s390/mm: Fix DirectMap accounting
|
|
Select FB_CORE if GEM's DMA and TTM implementations support fbdev
emulation. Fixes linker errors about missing symbols from the fbdev
subsystem.
Also see [1] for a related SHMEM fix.
Fixes: dadd28d4142f ("drm/client: Add client-lib module")
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/series/141411/ # 1
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20241216074450.8590-3-tzimmermann@suse.de
|
|
Do not select BACKLIGHT_CLASS_DEVICE from FB_BACKLIGHT. The latter
only controls backlight support within fbdev core code and data
structures.
Make fbdev drivers depend on BACKLIGHT_CLASS_DEVICE and let users
select it explicitly. Fixes warnings about recursive dependencies,
such as
error: recursive dependency detected!
symbol BACKLIGHT_CLASS_DEVICE is selected by FB_BACKLIGHT
symbol FB_BACKLIGHT is selected by FB_SH_MOBILE_LCDC
symbol FB_SH_MOBILE_LCDC depends on FB_DEVICE
symbol FB_DEVICE depends on FB_CORE
symbol FB_CORE is selected by DRM_GEM_DMA_HELPER
symbol DRM_GEM_DMA_HELPER is selected by DRM_PANEL_ILITEK_ILI9341
symbol DRM_PANEL_ILITEK_ILI9341 depends on BACKLIGHT_CLASS_DEVICE
BACKLIGHT_CLASS_DEVICE is user-selectable, so making drivers adapt to
it is the correct approach in any case. For most drivers, backlight
support is also configurable separately.
v3:
- Select BACKLIGHT_CLASS_DEVICE in PowerMac defconfigs (Christophe)
- Fix PMAC_BACKLIGHT module dependency corner cases (Christophe)
v2:
- s/BACKLIGHT_DEVICE_CLASS/BACKLIGHT_CLASS_DEVICE (Helge)
- Fix fbdev driver-dependency corner case (Arnd)
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20241216074450.8590-2-tzimmermann@suse.de
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs
Pull erofs fixes from Gao Xiang:
"The first one fixes a syzbot UAF report caused by a commit introduced
in this cycle, but it also addresses a longstanding memory leak. The
second one resolves a PSI memstall mis-accounting issue.
The remaining patches switch file-backed mounts to use buffered I/Os
by default instead of direct I/Os, since the page cache of underlay
files is typically valid and maybe even dirty. This change also aligns
with the default policy of loopback devices. A mount option has been
added to try to use direct I/Os explicitly.
Summary:
- Fix (pcluster) memory leak and (sbi) UAF after umounting
- Fix a case of PSI memstall mis-accounting
- Use buffered I/Os by default for file-backed mounts"
* tag 'erofs-for-6.13-rc4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: use buffered I/O for file-backed mounts by default
erofs: reference `struct erofs_device_info` for erofs_map_dev
erofs: use `struct erofs_device_info` for the primary device
erofs: add erofs_sb_free() helper
MAINTAINERS: erofs: update Yue Hu's email address
erofs: fix PSI memstall accounting
erofs: fix rare pcluster memory leak after unmounting
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull hardening fix from Kees Cook:
"Silence a GCC value-range warning that is being ironically triggered
by bounds checking"
* tag 'hardening-v6.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
fortify: Hide run-time copy size from value range tracking
|
|
The TP_printk() portion of a trace event is executed at the time a event
is read from the trace. This can happen seconds, minutes, hours, days,
months, years possibly later since the event was recorded. If the print
format contains a dereference to a string via "%s", and that string was
allocated, there's a chance that string could be freed before it is read
by the trace file.
To protect against such bugs, there are two functions that verify the
event. The first one is test_event_printk(), which is called when the
event is created. It reads the TP_printk() format as well as its arguments
to make sure nothing may be dereferencing a pointer that was not copied
into the ring buffer along with the event. If it is, it will trigger a
WARN_ON().
For strings that use "%s", it is not so easy. The string may not reside in
the ring buffer but may still be valid. Strings that are static and part
of the kernel proper which will not be freed for the life of the running
system, are safe to dereference. But to know if it is a pointer to a
static string or to something on the heap can not be determined until the
event is triggered.
This brings us to the second function that tests for the bad dereferencing
of strings, trace_check_vprintf(). It would walk through the printf format
looking for "%s", and when it finds it, it would validate that the pointer
is safe to read. If not, it would produces a WARN_ON() as well and write
into the ring buffer "[UNSAFE-MEMORY]".
The problem with this is how it used va_list to have vsnprintf() handle
all the cases that it didn't need to check. Instead of re-implementing
vsnprintf(), it would make a copy of the format up to the %s part, and
call vsnprintf() with the current va_list ap variable, where the ap would
then be ready to point at the string in question.
For architectures that passed va_list by reference this was possible. For
architectures that passed it by copy it was not. A test_can_verify()
function was used to differentiate between the two, and if it wasn't
possible, it would disable it.
Even for architectures where this was feasible, it was a stretch to rely
on such a method that is undocumented, and could cause issues later on
with new optimizations of the compiler.
Instead, the first function test_event_printk() was updated to look at
"%s" as well. If the "%s" argument is a pointer outside the event in the
ring buffer, it would find the field type of the event that is the problem
and mark the structure with a new flag called "needs_test". The event
itself will be marked by TRACE_EVENT_FL_TEST_STR to let it be known that
this event has a field that needs to be verified before the event can be
printed using the printf format.
When the event fields are created from the field type structure, the
fields would copy the field type's "needs_test" value.
Finally, before being printed, a new function ignore_event() is called
which will check if the event has the TEST_STR flag set (if not, it
returns false). If the flag is set, it then iterates through the events
fields looking for the ones that have the "needs_test" flag set.
Then it uses the offset field from the field structure to find the pointer
in the ring buffer event. It runs the tests to make sure that pointer is
safe to print and if not, it triggers the WARN_ON() and also adds to the
trace output that the event in question has an unsafe memory access.
The ignore_event() makes the trace_check_vprintf() obsolete so it is
removed.
Link: https://lore.kernel.org/all/CAHk-=wh3uOnqnZPpR0PeLZZtyWbZLboZ7cHLCKRWsocvs9Y7hQ@mail.gmail.com/
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20241217024720.848621576@goodmis.org
Fixes: 5013f454a352c ("tracing: Add check of trace event print fmts for dereferencing pointers")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
|