tjh.dev
Linux kernel
============
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Pull smb server fixes from Steve French:
"Six SMB3 server fixes for various races found by RO0T Lab of Huawei:
- Fix oops when racing between oplock break ack and freeing file
- Simultaneous request fixes for parallel logoffs, and for parallel
lock requests
- Fixes for tree disconnect race, session expire race, and close/open
race"
* tag '6.6-rc4-ksmbd-server-fixes' of git://git.samba.org/ksmbd:
ksmbd: fix race condition between tree conn lookup and disconnect
ksmbd: fix race condition from parallel smb2 lock requests
ksmbd: fix race condition from parallel smb2 logoff requests
ksmbd: fix uaf in smb20_oplock_break_ack
ksmbd: fix race condition with fp
ksmbd: fix race condition between session lookup and expire
Pull misc scheduler fixes from Ingo Molnar:
- Two EEVDF fixes: one to fix sysctl_sched_base_slice propagation, and
to fix an avg_vruntime() corner-case.
- A cpufreq frequency scaling fix
* tag 'sched-urgent-2023-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpufreq: schedutil: Update next_freq when cpufreq_limits change
sched/eevdf: Fix avg_vruntime()
sched/eevdf: Also update slice on placement
if thread A in smb2_write is using work-tcon, other thread B use
smb2_tree_disconnect free the tcon, then thread A will use free'd tcon.
Time
+
Thread A | Thread A
smb2_write | smb2_tree_disconnect
|
|
| kfree(tree_conn)
|
// UAF! |
work->tcon->share_conf |
+
This patch add state, reference count and lock for tree conn to fix race
condition issue.
Reported-by: luosili <rootlab@huawei.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull misc x86 fixes from Ingo Molnar:
- Fix SEV-SNP guest crashes that may happen on NMIs
- Fix a potential SEV platform memory setup overflow
* tag 'x86-urgent-2023-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/sev: Change npages to unsigned long in snp_accept_memory()
x86/sev: Use the GHCB protocol when available for SNP CPUID requests
When cpufreq's policy is 'single', there is a scenario that will
cause sg_policy's next_freq to be unable to update.
When the CPU's util is always max, the cpufreq will be max,
and then if we change the policy's scaling_max_freq to be a
lower freq, indeed, the sg_policy's next_freq need change to
be the lower freq, however, because the cpu_is_busy, the next_freq
would keep the max_freq.
For example:
The cpu7 is a single CPU:
unisoc:/sys/devices/system/cpu/cpufreq/policy7 # while true;do done& [1] 4737
unisoc:/sys/devices/system/cpu/cpufreq/policy7 # taskset -p 80 4737
pid 4737's current affinity mask: ff
pid 4737's new affinity mask: 80
unisoc:/sys/devices/system/cpu/cpufreq/policy7 # cat scaling_max_freq
2301000
unisoc:/sys/devices/system/cpu/cpufreq/policy7 # cat scaling_cur_freq
2301000
unisoc:/sys/devices/system/cpu/cpufreq/policy7 # echo 2171000 > scaling_max_freq
unisoc:/sys/devices/system/cpu/cpufreq/policy7 # cat scaling_max_freq
2171000
At this time, the sg_policy's next_freq would stay at 2301000, which
is wrong.
To fix this, add a check for the ->need_freq_update flag.
[ mingo: Clarified the changelog. ]
Co-developed-by: Guohua Yan <guohua.yan@unisoc.com>
Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
Signed-off-by: Guohua Yan <guohua.yan@unisoc.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230719130527.8074-1-xuewen.yan@unisoc.com
There is a race condition issue between parallel smb2 lock request.
Time
+
Thread A | Thread A
smb2_lock | smb2_lock
|
insert smb_lock to lock_list |
spin_unlock(&work->conn->llist_lock) |
|
| spin_lock(&conn->llist_lock);
| kfree(cmp_lock);
|
// UAF! |
list_add(&smb_lock->llist, &rollback_list) +
This patch swaps the line for adding the smb lock to the rollback list and
adding the lock list of connection to fix the race issue.
Reported-by: luosili <rootlab@huawei.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull parisc fixes from Helge Deller:
- fix random faults in mmap'd memory on pre PA8800 processors
- fix boot crash with nr_cpus=1 on kernel command line
* tag 'parisc-for-6.6-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Restore __ldcw_align for PA-RISC 2.0 processors
parisc: Fix crash with nr_cpus=1 option
In snp_accept_memory(), the npages variables value is calculated from
phys_addr_t variables but is an unsigned int. A very large range passed
into snp_accept_memory() could lead to truncating npages to zero. This
doesn't happen at the moment but let's be prepared.
Fixes: 6c3211796326 ("x86/sev: Add SNP-specific unaccepted memory support")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/6d511c25576494f682063c9fb6c705b526a3757e.1687441505.git.thomas.lendacky@amd.com
The expectation is that placing a task at avg_vruntime() makes it
eligible. Turns out there is a corner case where this is not the case.
Specifically, avg_vruntime() relies on the fact that integer division
is a flooring function (eg. it discards the remainder). By this
property the value returned is slightly left of the true average.
However! when the average is a negative (relative to min_vruntime) the
effect is flipped and it becomes a ceil, with the result that the
returned value is just right of the average and thus not eligible.
Fixes: af4cf40470c2 ("sched/fair: Add cfs_rq::avg_vruntime")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
If parallel smb2 logoff requests come in before closing door, running
request count becomes more than 1 even though connection status is set to
KSMBD_SESS_NEED_RECONNECT. It can't get condition true, and sleep forever.
This patch fix race condition problem by returning error if connection
status was already set to KSMBD_SESS_NEED_RECONNECT.
Reported-by: luosili <rootlab@huawei.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Pull smb client fixes from Steve French:
- protect cifs/smb3 socket connect from BPF address overwrite
- fix case when directory leases disabled but wasting resources with
unneeded thread on each mount
* tag '6.6-rc4-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
smb: client: do not start laundromat thread on nohandlecache
smb: use kernel_connect() and kernel_bind()
Back in 2005, Kyle McMartin removed the 16-byte alignment for
ldcw semaphores on PA 2.0 machines (CONFIG_PA20). This broke
spinlocks on pre PA8800 processors. The main symptom was random
faults in mmap'd memory (e.g., gcc compilations, etc).
Unfortunately, the errata for this ldcw change is lost.
The issue is the 16-byte alignment required for ldcw semaphore
instructions can only be reduced to natural alignment when the
ldcw operation can be handled coherently in cache. Only PA8800
and PA8900 processors actually support doing the operation in
cache.
Aligning the spinlock dynamically adds two integer instructions
to each spinlock.
Tested on rp3440, c8000 and a500.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Link: https://lore.kernel.org/linux-parisc/6b332788-2227-127f-ba6d-55e99ecf4ed8@bell.net/T/#t
Link: https://lore.kernel.org/linux-parisc/20050609050702.GB4641@roadwarrior.mcmartin.ca/
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
SNP retrieves the majority of CPUID information from the SNP CPUID page.
But there are times when that information needs to be supplemented by the
hypervisor, for example, obtaining the initial APIC ID of the vCPU from
leaf 1.
The current implementation uses the MSR protocol to retrieve the data from
the hypervisor, even when a GHCB exists. The problem arises when an NMI
arrives on return from the VMGEXIT. The NMI will be immediately serviced
and may generate a #VC requiring communication with the hypervisor.
Since a GHCB exists in this case, it will be used. As part of using the
GHCB, the #VC handler will write the GHCB physical address into the GHCB
MSR and the #VC will be handled.
When the NMI completes, processing resumes at the site of the VMGEXIT
which is expecting to read the GHCB MSR and find a CPUID MSR protocol
response. Since the NMI handling overwrote the GHCB MSR response, the
guest will see an invalid reply from the hypervisor and self-terminate.
Fix this problem by using the GHCB when it is available. Any NMI
received is properly handled because the GHCB contents are copied into
a backup page and restored on NMI exit, thus preserving the active GHCB
request or result.
[ bp: Touchups. ]
Fixes: ee0bfa08a345 ("x86/compressed/64: Add support for SEV-SNP CPUID table in #VC handlers")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/a5856fa1ebe3879de91a8f6298b6bbd901c61881.1690578565.git.thomas.lendacky@amd.com
Tasks that never consume their full slice would not update their slice value.
This means that tasks that are spawned before the sysctl scaling keep their
original (UP) slice length.
Fixes: 147f3efaa241 ("sched/fair: Implement an EEVDF-like scheduling policy")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230915124822.847197830@noisy.programming.kicks-ass.net
drop reference after use opinfo.
Signed-off-by: luosili <rootlab@huawei.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
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