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Linux kernel
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Parsing reparse point buffer is generic for all SMB versions and is already
implemented by global function parse_reparse_point().
Getting reparse point buffer from the SMB response is SMB version specific,
so introduce for it a new callback get_reparse_point_buffer.
This functionality split is needed for followup change - getting reparse
point buffer without parsing it.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Like previous changes for file inode.c, handle directory name surrogate
reparse points generally also in reparse.c.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
IO_REPARSE_TAG_MOUNT_POINT is just a specific case of directory Name
Surrogate reparse point. As reparse_info_to_fattr() already handles all
directory Name Surrogate reparse point (done by the previous change),
there is no need to have explicit case for IO_REPARSE_TAG_MOUNT_POINT.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Like in UNICODE mode, SMB1 Session Setup Kerberos Request contains oslm and
domain strings.
Extract common code into ascii_oslm_strings() and ascii_domain_string()
functions (similar to unicode variants) and use these functions in
non-UNICODE code path in sess_auth_kerberos().
Decision if non-UNICODE or UNICODE mode is used is based on the
SMBFLG2_UNICODE flag in Flags2 packed field, and not based on the
capabilities of server. Fix this check too.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
After commit f7025d861694 ("smb: client: allocate crypto only for
primary server") and commit b0abcd65ec54 ("smb: client: fix UAF in
async decryption"), the channels started reusing AEAD TFM from primary
channel to perform synchronous decryption, but that can't done as
there could be multiple cifsd threads (one per channel) simultaneously
accessing it to perform decryption.
This fixes the following KASAN splat when running fstest generic/249
with 'vers=3.1.1,multichannel,max_channels=4,seal' against Windows
Server 2022:
BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xba/0x110
Read of size 8 at addr ffff8881046c18a0 by task cifsd/986
CPU: 3 UID: 0 PID: 986 Comm: cifsd Not tainted 6.15.0-rc1 #1
PREEMPT(voluntary)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-3.fc41
04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x5d/0x80
print_report+0x156/0x528
? gf128mul_4k_lle+0xba/0x110
? __virt_addr_valid+0x145/0x300
? __phys_addr+0x46/0x90
? gf128mul_4k_lle+0xba/0x110
kasan_report+0xdf/0x1a0
? gf128mul_4k_lle+0xba/0x110
gf128mul_4k_lle+0xba/0x110
ghash_update+0x189/0x210
shash_ahash_update+0x295/0x370
? __pfx_shash_ahash_update+0x10/0x10
? __pfx_shash_ahash_update+0x10/0x10
? __pfx_extract_iter_to_sg+0x10/0x10
? ___kmalloc_large_node+0x10e/0x180
? __asan_memset+0x23/0x50
crypto_ahash_update+0x3c/0xc0
gcm_hash_assoc_remain_continue+0x93/0xc0
crypt_message+0xe09/0xec0 [cifs]
? __pfx_crypt_message+0x10/0x10 [cifs]
? _raw_spin_unlock+0x23/0x40
? __pfx_cifs_readv_from_socket+0x10/0x10 [cifs]
decrypt_raw_data+0x229/0x380 [cifs]
? __pfx_decrypt_raw_data+0x10/0x10 [cifs]
? __pfx_cifs_read_iter_from_socket+0x10/0x10 [cifs]
smb3_receive_transform+0x837/0xc80 [cifs]
? __pfx_smb3_receive_transform+0x10/0x10 [cifs]
? __pfx___might_resched+0x10/0x10
? __pfx_smb3_is_transform_hdr+0x10/0x10 [cifs]
cifs_demultiplex_thread+0x692/0x1570 [cifs]
? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
? rcu_is_watching+0x20/0x50
? rcu_lockdep_current_cpu_online+0x62/0xb0
? find_held_lock+0x32/0x90
? kvm_sched_clock_read+0x11/0x20
? local_clock_noinstr+0xd/0xd0
? trace_irq_enable.constprop.0+0xa8/0xe0
? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
kthread+0x1fe/0x380
? kthread+0x10f/0x380
? __pfx_kthread+0x10/0x10
? local_clock_noinstr+0xd/0xd0
? ret_from_fork+0x1b/0x60
? local_clock+0x15/0x30
? lock_release+0x29b/0x390
? rcu_is_watching+0x20/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork+0x31/0x60
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Tested-by: David Howells <dhowells@redhat.com>
Reported-by: Steve French <stfrench@microsoft.com>
Closes: https://lore.kernel.org/r/CAH2r5mu6Yc0-RJXM3kFyBYUB09XmXBrNodOiCVR4EDrmxq5Szg@mail.gmail.com
Fixes: f7025d861694 ("smb: client: allocate crypto only for primary server")
Fixes: b0abcd65ec54 ("smb: client: fix UAF in async decryption")
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
MS-FSCC in section 2.1.2.7 LX SYMLINK REPARSE_DATA_BUFFER now contains
documentation about WSL symlink reparse point buffers.
https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-fscc/68337353-9153-4ee1-ac6b-419839c3b7ad
Fix the struct reparse_wsl_symlink_data_buffer to reflect buffer fields
according to the MS-FSCC documentation.
Fix the Linux SMB client to correctly fill the WSL symlink reparse point
buffer when creaing new WSL-style symlink. There was a mistake during
filling the data part of the reparse point buffer. It should starts with
bytes "\x02\x00\x00\x00" (which represents version 2) but this constant was
written as number 0x02000000 encoded in little endian, which resulted bytes
"\x00\x00\x00\x02". This change is fixing this mistake.
Fixes: 4e2043be5c14 ("cifs: Add support for creating WSL-style symlinks")
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
When mounting the same share twice, once with the "linux" mount parameter
(or equivalently "posix") and then once without (or e.g. with "nolinux"),
we were incorrectly reusing the same tree connection for both mounts.
This meant that the first mount of the share on the client, would
cause subsequent mounts of that same share on the same client to
ignore that mount parm ("linux" vs. "nolinux") and incorrectly reuse
the same tcon.
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
Fix regression in mounts to e.g. onedrive shares.
Generally, reparse points are processed by the SMB server during the
SMB OPEN request, but there are few reparse points which do not have
OPEN-like meaning for the SMB server and has to be processed by the SMB
client. Those are symlinks and special files (fifo, socket, block, char).
For Linux SMB client, it is required to process also name surrogate reparse
points as they represent another entity on the SMB server system. Linux
client will mark them as separate mount points. Examples of name surrogate
reparse points are NTFS junction points (e.g. created by the "mklink" tool
on Windows servers).
So after processing the name surrogate reparse points, clear the
-EOPNOTSUPP error code returned from the parse_reparse_point() to let SMB
server to process reparse points.
And remove printing misleading error message "unhandled reparse tag:" as
reparse points are handled by SMB server and hence unhandled fact is normal
operation.
Fixes: cad3fc0a4c8c ("cifs: Throw -EOPNOTSUPP error on unsupported reparse point type from parse_reparse_point()")
Fixes: b587fd128660 ("cifs: Treat unhandled directory name surrogate reparse points as mount directory nodes")
Cc: stable@vger.kernel.org
Reported-by: Junwen Sun <sunjw8888@gmail.com>
Tested-by: Junwen Sun <sunjw8888@gmail.com>
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
The "real" linux/types.h UAPI header gracefully degrades to a NOOP when
included from assembly code.
Mirror this behaviour in the tools/ variant.
Test for __ASSEMBLER__ over __ASSEMBLY__ as the former is provided by the
toolchain automatically.
Reported-by: Mark Brown <broonie@kernel.org>
Closes: https://lore.kernel.org/lkml/af553c62-ca2f-4956-932c-dd6e3a126f58@sirena.org.uk/
Fixes: c9fbaa879508 ("selftests: vDSO: parse_vdso: Use UAPI headers instead of libc headers")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://patch.msgid.link/20250321-uapi-consistency-v1-1-439070118dc0@linutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull turbostat updates from Len Brown:
- support up to 8192 processors
- add cpuidle governor debug telemetry, disabled by default
- update default output to exclude cpuidle invocation counts
- bug fixes
* tag 'turbostat-2025.05.06' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
tools/power turbostat: v2025.05.06
tools/power turbostat: disable "cpuidle" invocation counters, by default
tools/power turbostat: re-factor sysfs code
tools/power turbostat: Restore GFX sysfs fflush() call
tools/power turbostat: Document GNR UncMHz domain convention
tools/power turbostat: report CoreThr per measurement interval
tools/power turbostat: Increase CPU_SUBSET_MAXCPUS to 8192
tools/power turbostat: Add idle governor statistics reporting
tools/power turbostat: Fix names matching
tools/power turbostat: Allow Zero return value for some RAPL registers
tools/power turbostat: Clustered Uncore MHz counters should honor show/hide options
Pull soundwire fix from Vinod Koul:
- add missing config symbol CONFIG_SND_HDA_EXT_CORE required for asoc
driver CONFIG_SND_SOF_SOF_HDA_SDW_BPT
* tag 'soundwire-6.15-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/soundwire:
ASoC: SOF: Intel: Let SND_SOF_SOF_HDA_SDW_BPT select SND_HDA_EXT_CORE
Support up to 8192 processors
Add cpuidle governor debug telemetry, disabled by default
Update default output to exclude cpuidle invocation counts
Bug fixes
Signed-off-by: Len Brown <len.brown@intel.com>
Pull perf event fix from Ingo Molnar:
"Fix a perf events time accounting bug"
* tag 'perf-urgent-2025-04-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix child_total_time_enabled accounting bug at task exit
CONFIG_SND_HDA_EXT_CORE is required for CONFIG_SND_SOF_SOF_HDA_SDW_BPT.
Fixes: 5d5cb86fb46e ("ASoC: SOF: Intel: hda-sdw-bpt: add helpers for SoundWire BPT DMA")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202503170249.iPSBJSf5-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202503162042.2cNgaBmC-lkp@intel.com/
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20250321023032.7420-2-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Create "pct_idle" counter group, the sofware notion of residency
so it can now be singled out, independent of other counter groups.
Create "cpuidle" group, the cpuidle invocation counts.
Disable "cpuidle", by default.
Create "swidle" = "cpuidle" + "pct_idle".
Undocument "sysfs", the old name for "swidle", but keep it working
for backwards compatibilty.
Create "hwidle", all the HW idle counters
Modify "idle", enabled by default
"idle" = "hwidle" + "pct_idle" (and now excludes "cpuidle")
Signed-off-by: Len Brown <len.brown@intel.com>
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