Linux kernel
============
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several of them using the reStructuredText markup notation.
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the problems which may result by upgrading your kernel.
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The change to have cpa_flush() call flush_kernel_pages() introduced
a bug where __cpa_addr() can access an address one larger than the
largest one in the cpa->pages array.
KASAN reports the issue like this:
BUG: KASAN: slab-out-of-bounds in __cpa_addr arch/x86/mm/pat/set_memory.c:309 [inline]
BUG: KASAN: slab-out-of-bounds in __cpa_addr+0x1d3/0x220 arch/x86/mm/pat/set_memory.c:306
Read of size 8 at addr ffff88801f75e8f8 by task syz.0.17/5978
This bug could cause cpa_flush() to not properly flush memory,
which somehow never showed any symptoms in my tests, possibly
because cpa_flush() is called so rarely, but could potentially
cause issues for other people.
Fix the issue by directly calculating the flush end address
from the start address.
Fixes: 86e6815b316e ("x86/mm: Change cpa_flush() to call flush_kernel_range() directly")
Reported-by: syzbot+afec6555eef563c66c97@syzkaller.appspotmail.com
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Kiryl Shutsemau <kas@kernel.org>
Link: https://lore.kernel.org/all/68e2ff90.050a0220.2c17c1.0038.GAE@google.com/
Users can create as many monitoring groups as the number of RMIDs supported
by the hardware. However, on AMD systems, only a limited number of RMIDs
are guaranteed to be actively tracked by the hardware. RMIDs that exceed
this limit are placed in an "Unavailable" state.
When a bandwidth counter is read for such an RMID, the hardware sets
MSR_IA32_QM_CTR.Unavailable (bit 62). When such an RMID starts being tracked
again the hardware counter is reset to zero. MSR_IA32_QM_CTR.Unavailable
remains set on first read after tracking re-starts and is clear on all
subsequent reads as long as the RMID is tracked.
resctrl miscounts the bandwidth events after an RMID transitions from the
"Unavailable" state back to being tracked. This happens because when the
hardware starts counting again after resetting the counter to zero, resctrl
in turn compares the new count against the counter value stored from the
previous time the RMID was tracked.
This results in resctrl computing an event value that is either undercounting
(when new counter is more than stored counter) or a mistaken overflow (when
new counter is less than stored counter).
Reset the stored value (arch_mbm_state::prev_msr) of MSR_IA32_QM_CTR to
zero whenever the RMID is in the "Unavailable" state to ensure accurate
counting after the RMID resets to zero when it starts to be tracked again.
Example scenario that results in mistaken overflow
==================================================
1. The resctrl filesystem is mounted, and a task is assigned to a
monitoring group.
$mount -t resctrl resctrl /sys/fs/resctrl
$mkdir /sys/fs/resctrl/mon_groups/test1/
$echo 1234 > /sys/fs/resctrl/mon_groups/test1/tasks
$cat /sys/fs/resctrl/mon_groups/test1/mon_data/mon_L3_*/mbm_total_bytes
21323 <- Total bytes on domain 0
"Unavailable" <- Total bytes on domain 1
Task is running on domain 0. Counter on domain 1 is "Unavailable".
2. The task runs on domain 0 for a while and then moves to domain 1. The
counter starts incrementing on domain 1.
$cat /sys/fs/resctrl/mon_groups/test1/mon_data/mon_L3_*/mbm_total_bytes
7345357 <- Total bytes on domain 0
4545 <- Total bytes on domain 1
3. At some point, the RMID in domain 0 transitions to the "Unavailable"
state because the task is no longer executing in that domain.
$cat /sys/fs/resctrl/mon_groups/test1/mon_data/mon_L3_*/mbm_total_bytes
"Unavailable" <- Total bytes on domain 0
434341 <- Total bytes on domain 1
4. Since the task continues to migrate between domains, it may eventually
return to domain 0.
$cat /sys/fs/resctrl/mon_groups/test1/mon_data/mon_L3_*/mbm_total_bytes
17592178699059 <- Overflow on domain 0
3232332 <- Total bytes on domain 1
In this case, the RMID on domain 0 transitions from "Unavailable" state to
active state. The hardware sets MSR_IA32_QM_CTR.Unavailable (bit 62) when
the counter is read and begins tracking the RMID counting from 0.
Subsequent reads succeed but return a value smaller than the previously
saved MSR value (7345357). Consequently, the resctrl's overflow logic is
triggered, it compares the previous value (7345357) with the new, smaller
value and incorrectly interprets this as a counter overflow, adding a large
delta.
In reality, this is a false positive: the counter did not overflow but was
simply reset when the RMID transitioned from "Unavailable" back to active
state.
Here is the text from APM [1] available from [2].
"In PQOS Version 2.0 or higher, the MBM hardware will set the U bit on the
first QM_CTR read when it begins tracking an RMID that it was not
previously tracking. The U bit will be zero for all subsequent reads from
that RMID while it is still tracked by the hardware. Therefore, a QM_CTR
read with the U bit set when that RMID is in use by a processor can be
considered 0 when calculating the difference with a subsequent read."
[1] AMD64 Architecture Programmer's Manual Volume 2: System Programming
Publication # 24593 Revision 3.41 section 19.3.3 Monitoring L3 Memory
Bandwidth (MBM).
[ bp: Split commit message into smaller paragraph chunks for better
consumption. ]
Fixes: 4d05bf71f157d ("x86/resctrl: Introduce AMD QOS feature")
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: stable@vger.kernel.org # needs adjustments for <= v6.17
Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 # [2]
Pull i2c fix from Wolfram Sang:
"One revert because of a regression in the I2C core which has sadly not
showed up during its time in -next"
* tag 'i2c-for-6.18-rc1-hotfix' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
Revert "i2c: boardinfo: Annotate code used in init phase only"
Pull irq fixes from Borislav Petkov:
- Skip interrupt ID 0 in sifive-plic during suspend/resume because
ID 0 is reserved and accessing reserved register space could result
in undefined behavior
- Fix a function's retval check in aspeed-scu-ic
* tag 'irq_urgent_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/sifive-plic: Avoid interrupt ID 0 handling during suspend/resume
irqchip/aspeed-scu-ic: Fix an IS_ERR() vs NULL check
This reverts commit 1a2b423be6a89dd07d5fc27ea042be68697a6a49 because we
got a regression report and need time to find out the details.
Reported-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Closes: https://lore.kernel.org/r/29ec0082-4dd4-4120-acd2-44b35b4b9487@oss.qualcomm.com
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Pull tracing fixes from Steven Rostedt:
"The previous fix to trace_marker required updating trace_marker_raw as
well. The difference between trace_marker_raw from trace_marker is
that the raw version is for applications to write binary structures
directly into the ring buffer instead of writing ASCII strings. This
is for applications that will read the raw data from the ring buffer
and get the data structures directly. It's a bit quicker than using
the ASCII version.
Unfortunately, it appears that our test suite has several tests that
test writes to the trace_marker file, but lacks any tests to the
trace_marker_raw file (this needs to be remedied). Two issues came
about the update to the trace_marker_raw file that syzbot found:
- Fix tracing_mark_raw_write() to use per CPU buffer
The fix to use the per CPU buffer to copy from user space was
needed for both the trace_maker and trace_maker_raw file.
The fix for reading from user space into per CPU buffers properly
fixed the trace_marker write function, but the trace_marker_raw
file wasn't fixed properly. The user space data was correctly
written into the per CPU buffer, but the code that wrote into the
ring buffer still used the user space pointer and not the per CPU
buffer that had the user space data already written.
- Stop the fortify string warning from writing into trace_marker_raw
After converting the copy_from_user_nofault() into a memcpy(),
another issue appeared. As writes to the trace_marker_raw expects
binary data, the first entry is a 4 byte identifier. The entry
structure is defined as:
struct {
struct trace_entry ent;
int id;
char buf[];
};
The size of this structure is reserved on the ring buffer with:
size = sizeof(*entry) + cnt;
Then it is copied from the buffer into the ring buffer with:
memcpy(&entry->id, buf, cnt);
This use to be a copy_from_user_nofault(), but now converting it to
a memcpy() triggers the fortify-string code, and causes a warning.
The allocated space is actually more than what is copied, as the
cnt used also includes the entry->id portion. Allocating
sizeof(*entry) plus cnt is actually allocating 4 bytes more than
what is needed.
Change the size function to:
size = struct_size(entry, buf, cnt - sizeof(entry->id));
And update the memcpy() to unsafe_memcpy()"
* tag 'trace-v6.18-3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: Stop fortify-string from warning in tracing_mark_raw_write()
tracing: Fix tracing_mark_raw_write() to use buf and not ubuf
According to the PLIC specification[1], global interrupt sources are
assigned small unsigned integer identifiers beginning at the value 1.
An interrupt ID of 0 is reserved to mean "no interrupt".
The current plic_irq_resume() and plic_irq_suspend() functions incorrectly
start the loop from index 0, which accesses the register space for the
reserved interrupt ID 0.
Change the loop to start from index 1, skipping the reserved
interrupt ID 0 as per the PLIC specification.
This prevents potential undefined behavior when accessing the reserved
register space during suspend/resume cycles.
Fixes: e80f0b6a2cf3 ("irqchip/irq-sifive-plic: Add syscore callbacks for hibernation")
Co-developed-by: Jia Wang <wangjia@ultrarisc.com>
Signed-off-by: Jia Wang <wangjia@ultrarisc.com>
Co-developed-by: Charles Mirabile <cmirabil@redhat.com>
Signed-off-by: Charles Mirabile <cmirabil@redhat.com>
Signed-off-by: Lucas Zampieri <lzampier@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://github.com/riscv/riscv-plic-spec/releases/tag/1.0.0
Pull RTC updates from Alexandre Belloni:
"This cycle, we have a new RTC driver, for the SpacemiT P1. The optee
driver gets alarm support. We also get a fix for a race condition that
was fairly rare unless while stress testing the alarms.
Subsystem:
- Fix race when setting alarm
- Ensure alarm irq is enabled when UIE is enabled
- remove unneeded 'fast_io' parameter in regmap_config
New driver:
- SpacemiT P1 RTC
Drivers:
- efi: Remove wakeup functionality
- optee: add alarms support
- s3c: Drop support for S3C2410
- zynqmp: Restore alarm functionality after kexec transition"
* tag 'rtc-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (29 commits)
rtc: interface: Ensure alarm irq is enabled when UIE is enabled
rtc: tps6586x: Fix initial enable_irq/disable_irq balance
rtc: cpcap: Fix initial enable_irq/disable_irq balance
rtc: isl12022: Fix initial enable_irq/disable_irq balance
rtc: interface: Fix long-standing race when setting alarm
rtc: pcf2127: fix watchdog interrupt mask on pcf2131
rtc: zynqmp: Restore alarm functionality after kexec transition
rtc: amlogic-a4: Optimize global variables
rtc: sd2405al: Add I2C address.
rtc: Kconfig: move symbols to proper section
rtc: optee: make optee_rtc_pm_ops static
rtc: optee: Fix error code in optee_rtc_read_alarm()
rtc: optee: fix error code in probe()
dt-bindings: rtc: Convert apm,xgene-rtc to DT schema
rtc: spacemit: support the SpacemiT P1 RTC
rtc: optee: add alarm related rtc ops to optee rtc driver
rtc: optee: remove unnecessary memory operations
rtc: optee: fix memory leak on driver removal
rtc: x1205: Fix Xicor X1205 vendor prefix
dt-bindings: rtc: Fix Xicor X1205 vendor prefix
...
Pull Kbuild fixes from Nathan Chancellor:
- Fix UAPI types check in headers_check.pl
- Only enable -Werror for hostprogs with CONFIG_WERROR / W=e
- Ignore fsync() error when output of gen_init_cpio is a pipe
- Several little build fixes for recent modules.builtin.modinfo series
* tag 'kbuild-fixes-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux:
kbuild: Use '--strip-unneeded-symbol' for removing module device table symbols
s390/vmlinux.lds.S: Move .vmlinux.info to end of allocatable sections
kbuild: Add '.rel.*' strip pattern for vmlinux
kbuild: Restore pattern to avoid stripping .rela.dyn from vmlinux
gen_init_cpio: Ignore fsync() returning EINVAL on pipes
scripts/Makefile.extrawarn: Respect CONFIG_WERROR / W=e for hostprogs
kbuild: uapi: Strip comments before size type check
The way tracing_mark_raw_write() records its data is that it has the
following structure:
struct {
struct trace_entry;
int id;
char buf[];
};
But memcpy(&entry->id, buf, size) triggers the following warning when the
size is greater than the id:
------------[ cut here ]------------
memcpy: detected field-spanning write (size 6) of single field "&entry->id" at kernel/trace/trace.c:7458 (size 4)
WARNING: CPU: 7 PID: 995 at kernel/trace/trace.c:7458 write_raw_marker_to_buffer.isra.0+0x1f9/0x2e0
Modules linked in:
CPU: 7 UID: 0 PID: 995 Comm: bash Not tainted 6.17.0-test-00007-g60b82183e78a-dirty #211 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-debian-1.17.0-1 04/01/2014
RIP: 0010:write_raw_marker_to_buffer.isra.0+0x1f9/0x2e0
Code: 04 00 75 a7 b9 04 00 00 00 48 89 de 48 89 04 24 48 c7 c2 e0 b1 d1 b2 48 c7 c7 40 b2 d1 b2 c6 05 2d 88 6a 04 01 e8 f7 e8 bd ff <0f> 0b 48 8b 04 24 e9 76 ff ff ff 49 8d 7c 24 04 49 8d 5c 24 08 48
RSP: 0018:ffff888104c3fc78 EFLAGS: 00010292
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 1ffffffff6b363b4 RDI: 0000000000000001
RBP: ffff888100058a00 R08: ffffffffb041d459 R09: ffffed1020987f40
R10: 0000000000000007 R11: 0000000000000001 R12: ffff888100bb9010
R13: 0000000000000000 R14: 00000000000003e3 R15: ffff888134800000
FS: 00007fa61d286740(0000) GS:ffff888286cad000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560d28d509f1 CR3: 00000001047a4006 CR4: 0000000000172ef0
Call Trace:
<TASK>
tracing_mark_raw_write+0x1fe/0x290
? __pfx_tracing_mark_raw_write+0x10/0x10
? security_file_permission+0x50/0xf0
? rw_verify_area+0x6f/0x4b0
vfs_write+0x1d8/0xdd0
? __pfx_vfs_write+0x10/0x10
? __pfx_css_rstat_updated+0x10/0x10
? count_memcg_events+0xd9/0x410
? fdget_pos+0x53/0x5e0
ksys_write+0x182/0x200
? __pfx_ksys_write+0x10/0x10
? do_user_addr_fault+0x4af/0xa30
do_syscall_64+0x63/0x350
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fa61d318687
Code: 48 89 fa 4c 89 df e8 58 b3 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd87fe0120 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fa61d286740 RCX: 00007fa61d318687
RDX: 0000000000000006 RSI: 0000560d28d509f0 RDI: 0000000000000001
RBP: 0000560d28d509f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
R13: 00007fa61d4715c0 R14: 00007fa61d46ee80 R15: 0000000000000000
</TASK>
---[ end trace 0000000000000000 ]---
This is because fortify string sees that the size of entry->id is only 4
bytes, but it is writing more than that. But this is OK as the
dynamic_array is allocated to handle that copy.
The size allocated on the ring buffer was actually a bit too big:
size = sizeof(*entry) + cnt;
But cnt includes the 'id' and the buffer data, so adding cnt to the size
of *entry actually allocates too much on the ring buffer.
Change the allocation to:
size = struct_size(entry, buf, cnt - sizeof(entry->id));
and the memcpy() to unsafe_memcpy() with an added justification.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20251011112032.77be18e4@gandalf.local.home
Fixes: 64cf7d058a00 ("tracing: Have trace_marker use per-cpu data to read user space")
Reported-by: syzbot+9a2ede1643175f350105@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68e973f5.050a0220.1186a4.0010.GAE@google.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
of_iomap() doesn't return error pointers, it returns NULL. Fix the error
checking to check for NULL pointers.
Fixes: 86cd4301c285 ("irqchip/aspeed-scu-ic: Refactor driver to support variant-based initialization")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pull SCSI fixes from James Bottomley:
"Fixes only in drivers (ufs, mvsas, qla2xxx, target) that came in just
before or during the merge window.
The most important one is the qla2xxx which reverts a conversion to
fix flexible array member warnings, that went up in this merge window
but which turned out on further testing to be causing data corruption"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: ufs: core: Include UTP error in INT_FATAL_ERRORS
scsi: ufs: sysfs: Make HID attributes visible
scsi: mvsas: Fix use-after-free bugs in mvs_work_queue
scsi: ufs: core: Fix PM QoS mutex initialization
scsi: ufs: core: Fix runtime suspend error deadlock
Revert "scsi: qla2xxx: Fix memcpy() field-spanning write issue"
scsi: target: target_core_configfs: Add length check to avoid buffer overflow
When setting a normal alarm, user-space is responsible for using
RTC_AIE_ON/RTC_AIE_OFF to control if alarm irq should be enabled.
But when RTC_UIE_ON is used, interrupts must be enabled so that the
requested irq events are generated.
When RTC_UIE_OFF is used, alarm irq is disabled if there are no other
alarms queued, so this commit brings symmetry to that.
Signed-off-by: Esben Haabendal <esben@geanix.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250516-rtc-uie-irq-fixes-v2-5-3de8e530a39e@geanix.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
After commit 5ab23c7923a1 ("modpost: Create modalias for builtin
modules"), relocatable RISC-V kernels with CONFIG_KASAN=y start failing
when attempting to strip the module device table symbols:
riscv64-linux-objcopy: not stripping symbol `__mod_device_table__kmod_irq_starfive_jh8100_intc__of__starfive_intc_irqchip_match_table' because it is named in a relocation
make[4]: *** [scripts/Makefile.vmlinux:97: vmlinux] Error 1
The relocation appears to come from .LASANLOC5 in .data.rel.local:
$ llvm-objdump --disassemble-symbols=.LASANLOC5 --disassemble-all -r drivers/irqchip/irq-starfive-jh8100-intc.o
drivers/irqchip/irq-starfive-jh8100-intc.o: file format elf64-littleriscv
Disassembly of section .data.rel.local:
0000000000000180 <.LASANLOC5>:
...
1d0: 0000 unimp
00000000000001d0: R_RISCV_64 __mod_device_table__kmod_irq_starfive_jh8100_intc__of__starfive_intc_irqchip_match_table
...
This section appears to come from GCC for including additional
information about global variables that may be protected by KASAN.
There appears to be no way to opt out of the generation of these symbols
through either a flag or attribute. Attempting to remove '.LASANLOC*'
with '--strip-symbol' results in the same error as above because these
symbols may refer to (thus have relocation between) each other.
Avoid this build breakage by switching to '--strip-unneeded-symbol' for
removing __mod_device_table__ symbols, as it will only remove the symbol
when there is no relocation pointing to it. While this may result in a
little more bloat in the symbol table in certain configurations, it is
not as bad as outright build failures.
Fixes: 5ab23c7923a1 ("modpost: Create modalias for builtin modules")
Reported-by: Charles Mirabile <cmirabil@redhat.com>
Closes: https://lore.kernel.org/20251007011637.2512413-1-cmirabil@redhat.com/
Suggested-by: Alexey Gladkov <legion@kernel.org>
Tested-by: Nicolas Schier <nsc@kernel.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
The fix to use a per CPU buffer to read user space tested only the writes
to trace_marker. But it appears that the selftests are missing tests to
the trace_maker_raw file. The trace_maker_raw file is used by applications
that writes data structures and not strings into the file, and the tools
read the raw ring buffer to process the structures it writes.
The fix that reads the per CPU buffers passes the new per CPU buffer to
the trace_marker file writes, but the update to the trace_marker_raw write
read the data from user space into the per CPU buffer, but then still used
then passed the user space address to the function that records the data.
Pass in the per CPU buffer and not the user space address.
TODO: Add a test to better test trace_marker_raw.
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>
Link: https://lore.kernel.org/20251011035243.386098147@kernel.org
Fixes: 64cf7d058a00 ("tracing: Have trace_marker use per-cpu data to read user space")
Reported-by: syzbot+9a2ede1643175f350105@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68e973f5.050a0220.1186a4.0010.GAE@google.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>