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1,464,522 commits

Author SHA1 Message Date
Wentao Liang
3b09ff5411 net: qrtr: fix node refcount leak on ctrl packet alloc failure
qrtr_send_resume_tx() calls qrtr_node_lookup() which takes a
reference on the returned node. If the subsequent call to
qrtr_alloc_ctrl_packet() fails due to memory allocation failure, the
function returns -ENOMEM without calling qrtr_node_release() to
release the node reference.

Add qrtr_node_release(node) before returning on the allocation failure
path to properly release the reference.

Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://patch.msgid.link/20260528080019.1176700-1-vulab@iscas.ac.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:53:45 -07:00
David Thompson
e3c6508a46 net: lan743x: avoid netdev-based logging before netdev registration
This patch updates the lan743x driver to prevent the use of netdev-based
logging APIs (such as netdev_dbg) before the network device has been
successfully registered. Using netdev-based logging prior to registration
results in log messages referencing "(unnamed net_device) (uninitialized)",
which can be confusing and less informative.

The driver must use netif_msg_ APIs and device-based logging (e.g. dev_dbg)
until netdev registration is complete. This ensures log entries are
associated with the correct device context and improves log clarity. After
registration, netdev-based logging APIs can be used safely.

Signed-off-by: David Thompson <davthompson@nvidia.com>
Link: https://patch.msgid.link/20260528165017.421576-1-davthompson@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:52:24 -07:00
Linus Torvalds
4b5821f73b auxdisplay for v7.2-1
* Fix potential out-of-bound access in line-display library
 * Miscellaneous refactoring and cleaning up
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Merge tag 'auxdisplay-v7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/andy/linux-auxdisplay

Pull auxdisplay updates from Andy Shevchenko:

 - Fix potential out-of-bound access in line-display library

 - Miscellaneous refactoring and cleaning up

[ Andy says this could easily be delayed until 7.2, but it's _so_ tiny
  that it's more work for me to schedule it for later than to just take
  it now, and just doesn't seem worth delaying    - Linus ]

* tag 'auxdisplay-v7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/andy/linux-auxdisplay:
  auxdisplay: Kconfig: drop unneeded quotes in PANEL_BOOT_MESSAGE dep
  auxdisplay: line-display: fix OOB read on zero-length message_store()
  auxdisplay: max6959: use regmap_assign_bits() in max6959_enable()
2026-06-01 19:50:33 -07:00
Lee Jones
a213a89504 l2tp: pppol2tp: hold reference to session in pppol2tp_ioctl()
pppol2tp_ioctl() read sock->sk->sk_user_data directly without any
locks or reference counting.  If a controllable sleep was induced during
copy_from_user() (e.g. via a userfaultfd page fault sleep), a concurrent
socket close could trigger pppol2tp_session_close() asynchronously.  This
frees the l2tp_session structure via the l2tp_session_del_work workqueue.
Upon resuming, the ioctl thread dereferences the stale session pointer,
resulting in a Use-After-Free (UAF).

Fix this by securely fetching the session reference using the RCU-safe,
refcounted helper pppol2tp_sock_to_session(sk) on entry.  This locks the
session's refcount across the sleep.  We structured the function to exit
via standard err breaks, guaranteeing that l2tp_session_put() is cleanly
called on all return paths to drop the reference.

To preserve existing behavior we validate the session and its magic
signature only for the specific L2TP commands that require it.  This
ensures that generic/unknown ioctls called on an unconnected socket
still return -ENOIOCTLCMD and correctly fall back to generic handlers
(e.g. in sock_do_ioctl()).

Signed-off-by: Lee Jones <lee@kernel.org>
Fixes: fd558d186d ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Link: https://patch.msgid.link/20260527133630.2120612-1-lee@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:40:46 -07:00
Chenguang Zhao
9c89f975e6 net: txgbe: fix phylink leak on AML init failure
Destroy the phylink instance when fixed-link setup fails.

Signed-off-by: Chenguang Zhao <zhaochenguang@kylinos.cn>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Jiawen Wu <jiawenwu@trustnetic.com>
Link: https://patch.msgid.link/20260528013258.129146-1-zhaochenguang@kylinos.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:27:20 -07:00
Rosen Penev
996ea50ee9 net: fec_mpc52xx_phy: Add missing MODULE_DESCRIPTION()
Fixes error during modpost:

WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/net/ethernet/freescale/fec_mpc52xx_phy.o

Signed-off-by: Rosen Penev <rosenp@gmail.com>
Link: https://patch.msgid.link/20260527025139.10188-1-rosenp@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:25:24 -07:00
Jose Ignacio Tornos Martinez
ae733795e5 net: wwan: t7xx: Add delay between MD and SAP suspend
SAP (Service Access Point) suspend occasionally times out with error
-110 (ETIMEDOUT), followed by modem port errors and complete modem
failure requiring a system reboot to recover.

Error symptoms:
  mtk_t7xx 0000:72:00.0: [PM] SAP suspend error: -110
  mtk_t7xx 0000:72:00.0: can't suspend (...returned -110)
  mtk_t7xx 0000:07:00.0: Failed to send skb: -22
  mtk_t7xx 0000:07:00.0: Write error on MBIM port, -22

The modem firmware needs time after receiving the MD (modem) suspend
request to complete internal operations before it is ready to accept
the SAP suspend request. Without this delay, if runtime PM attempts
to suspend while the firmware is busy, the SAP suspend command times
out, leaving the modem in an unrecoverable state.

Root cause and userspace interaction:
ModemManager 1.24+ includes changes that reduce the likelihood of this
issue by ensuring the modem is in a low-power state before the kernel
attempts runtime suspend. However, the kernel driver should not depend
on specific userspace behavior or ModemManager versions. Older versions
(1.20-1.22) are still widely deployed, and the kernel should be robust
regardless of userspace implementation details.

There appears to be no hardware status register or other mechanism
available to query whether the firmware is ready for SAP suspend.
A delay between the two suspend requests is the most reliable solution
found through testing.

Add a 50ms delay between MD suspend and SAP suspend. This gives the
firmware adequate time to complete internal operations without adding
significant latency to the suspend path. This makes the driver robust
across all ModemManager versions and system conditions.

Testing: 96+ hours of continuous operation with ModemManager 1.20.2
and Fibocom FM350-GL modem. Zero SAP suspend timeouts observed across
2000+ successful suspend/resume cycles. Previously failed within
24 hours with 100% reproducibility.

Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@redhat.com>
Reviewed-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
Link: https://patch.msgid.link/20260527061451.12710-1-jtornosm@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:20:23 -07:00
Petr Wozniak
8fe125892f net: phy: sfp: probe for RollBall I2C-to-MDIO bridge in mdio-i2c
The "OEM"/"SFP-10G-T" quirk entry in sfp_fixup_rollball_cc()
unconditionally forces MDIO_I2C_ROLLBALL for all modules matching that
vendor/part-number combination.  This works for modules that genuinely
implement a RollBall I2C-to-MDIO bridge, but silently breaks modules
that share the same EEPROM strings without having such a bridge.

The Realtek RTL8261BE-CG is one such module: a pure copper 10G SFP+
media converter with no I2C-to-MDIO bridge.  Its EEPROM reports
vendor="OEM", part="SFP-10G-T-I", and -- critically -- Vendor OUI
00:00:00, making OUI-based differentiation impossible.  With
MDIO_I2C_ROLLBALL forced, the module silently ACKs the unlock password
write, the MDIO bus is created, but no PHY responds; the SFP state
machine cycles through the RollBall PHY-probe retry window before
reporting no PHY.

Move the probe into i2c_mii_init_rollball() in mdio-i2c.c, where the
RollBall protocol constants are already defined.  After sending the
unlock password, issue a CMD_READ and poll for CMD_DONE up to 200 ms
(10 x 20 ms, matching the existing rollball poll tolerance).  A genuine
RollBall bridge asserts CMD_DONE within that window; modules without a
bridge never do, so i2c_mii_init_rollball() returns -ENODEV.
mdio_i2c_alloc() propagates -ENODEV to the caller to signal that no
bridge is present and PHY probing should be skipped.
sfp_sm_add_mdio_bus() catches -ENODEV and transitions
sfp->mdio_protocol to MDIO_I2C_NONE so the rest of the state machine
skips PHY probing for this module.

Any I2C-level error (NACK, timeout) during the probe is also treated as
-ENODEV: if the module does not respond at I2C address 0x51 at all,
there is certainly no RollBall bridge there, and SFP initialization
should not abort.

The probe writes are safe with respect to SFP EEPROM integrity: only
modules explicitly listed in the quirk table enter this path, and the
RollBall password unlock write to 0x51 was already issued by
i2c_mii_init_rollball() before the probe for all such modules.  Any
module without a device at 0x51 NACKs the transfer and is treated as
-ENODEV.

Add "OEM"/"SFP-10G-T-I" to the quirk table so RTL8261BE modules enter
the probe path; genuine RollBall modules continue to work as before.

Signed-off-by: Petr Wozniak <petr.wozniak@gmail.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/20260527053909.2118-1-petr.wozniak@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:19:27 -07:00
Jakub Kicinski
925f3ec7d3 Merge branch 'mv88e6xxx-serdes-on-mv88e6321'
Fidan Aliyeva says:

====================
mv88e6xxx: SERDES on mv88e6321

This patch series add code support to be able to use SERDES feature of
mv88e6321 version of Marvel mv88e6xxx series. mv88e6321 has 2 ports to
support high speed SERDES but the support is lacking in the driver.

mv88e6321 version has a similar architecture to mv88e6352 version making it
possible to reuse its pcs functions. That's why the patch series consist of
2 parts:

1. Refactor the serdes functions and pcs_init of mv88e6352 to be more
generic (patches 1-2).
2. Add the SERDES support for mv88e6321 reusing 6352's pcs functions

The final code has been tested on mv88e6321 ethernet device directly by ip
ping tests, performance tests and also verifying the switch's expected
register values.

Referred document: 88E6321/88E6320 Functional Specification
====================

Link: https://patch.msgid.link/20260528210310.1365858-1-fidan.aliyeva.ext@ericsson.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:11:17 -07:00
Fidan Aliyeva
f456c9b936 mv88e6xxx: Add SERDES Support for mv88e6321
Add serdes and pcs_ops functions for mv88e6321. In mv88e6321
2 ports support serdes functionality; port 0 and port 1. These ports are
serdes-only ports.

Changes:

1. Add a function support to return the lane address for the port based on
cmode.
2. Reuse mv88e6352's serdes_get_regs* and pcs_init functions for mv88e6321.

Tested on mv88e6321 switch port 0.

Co-developed-by: Thomas Eckerman <thomas.eckerman.ext@ericsson.com>
Signed-off-by: Thomas Eckerman <thomas.eckerman.ext@ericsson.com>
Signed-off-by: Fidan Aliyeva <fidan.aliyeva.ext@ericsson.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260528210310.1365858-4-fidan.aliyeva.ext@ericsson.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:11:14 -07:00
Fidan Aliyeva
348a46c93e mv88e6xxx: Refactor 6352's serdes functions
Changes:
1. Replace serdes check by mv88e6352_g2_scratch_port_has_serdes in
mv88e6352_pcs_init function by mv88e6xxx_serdes_get_lane function making it
more generic.
2. Replace serdes checks in mv88e6352_serdes_get_* functions with
mv88e6xxx_serdes_get_lane making them more generic.
3. Add lane argument to mv88e6352_serdes_read so it can be reused later for
6321.

Co-developed-by: Thomas Eckerman <thomas.eckerman.ext@ericsson.com>
Signed-off-by: Thomas Eckerman <thomas.eckerman.ext@ericsson.com>
Signed-off-by: Fidan Aliyeva <fidan.aliyeva.ext@ericsson.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260528210310.1365858-3-fidan.aliyeva.ext@ericsson.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:11:14 -07:00
Fidan Aliyeva
1a79978dd2 mv88e6xxx: Add mv88e6352_serdes_get_lane
Changes:
1. Add mv88e6352_serdes_get_lane function which checks if the port
supports SERDES by calling mv88e6352_g2_scratch_port_has_serdes. Then
returns the address of the SERDES lane.
2. Add this function as .serdes_get_lane member to all the chip
versions which use mv88e6352_pcs_init.

Co-developed-by: Thomas Eckerman <thomas.eckerman.ext@ericsson.com>
Signed-off-by: Thomas Eckerman <thomas.eckerman.ext@ericsson.com>
Signed-off-by: Fidan Aliyeva <fidan.aliyeva.ext@ericsson.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260528210310.1365858-2-fidan.aliyeva.ext@ericsson.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:11:14 -07:00
Yizhou Zhao
2a58899d11 6lowpan: fix off-by-one in multicast context address compression
The second memcpy in lowpan_iphc_mcast_ctx_addr_compress() uses
&data[1] as destination and &ipaddr->s6_addr[11] as source, but
both should be offset by one: &data[2] and &ipaddr->s6_addr[12]
respectively.

This off-by-one has two consequences:
1. data[1] is overwritten with s6_addr[11], corrupting the RIID
   field in the compressed multicast address
2. data[5] is never written, so uninitialized kernel stack memory
   is transmitted over the network via lowpan_push_hc_data(),
   leaking kernel stack contents

The correct inline data layout must match what the decompression
function lowpan_uncompress_multicast_ctx_daddr() expects:
  data[0..1] = s6_addr[1..2]  (flags/scope + RIID)
  data[2..5] = s6_addr[12..15] (group ID)

Also zero-initialize the data array as a defensive measure against
similar bugs in the future.

Fixes: 5609c185f2 ("6lowpan: iphc: add support for stateful compression")
Reported-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Reported-by: Yuxiang Yang <yangyx22@mails.tsinghua.edu.cn>
Reported-by: Ao Wang <wangao@seu.edu.cn>
Reported-by: Xuewei Feng <fengxw06@126.com>
Reported-by: Qi Li <qli01@tsinghua.edu.cn>
Reported-by: Ke Xu <xuke@tsinghua.edu.cn>
Signed-off-by: Yizhou Zhao <zhaoyz24@mails.tsinghua.edu.cn>
Acked-by: Alexander Aring <aahringo@redhat.com>
Link: https://patch.msgid.link/20260527081806.42747-1-zhaoyz24@mails.tsinghua.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:10:16 -07:00
Jakub Kicinski
046c89c45e Merge branch 'net-mdio-realtek-rtl9300-soc-independent-command-runner'
Markus Stockhausen says:

====================
net: mdio: realtek-rtl9300: SoC independent command runner

The Realtek Otto switch platform consist of four different series

- RTL838x aka maple   : 28 port 1G Switches
- RTL839x aka cypress : 52 port 1G Switches
- RTL930x aka longan  : 28 port 1G/2.5G/10G Switches
- RTL931x aka mango   : 56 port 1G/2.5G/10G Switches

After establishing basic groundwork for multi device support, this series
harmonizes the command handling of the MDIO driver. It is the second step
to allow easier integration of the non RTL930x SoCs into this driver.
====================

Link: https://patch.msgid.link/20260527163449.1294961-1-markus.stockhausen@gmx.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:06:52 -07:00
Markus Stockhausen
2e3c28c715 net: mdio: realtek-rtl9300: use command runner for read_c22()
Convert the final missing read_c22() path to the new read enabled command
runner. Do it the same way as other implementations.

- bus calls otto_emdio_read_c22()
- this hands over to SoC specific otto_emdio_9300_read_c22()
- finally the registers are filled and the runner issued

With this cleanup remove the obsolete helper otto_emdio_wait_ready()

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260527163449.1294961-5-markus.stockhausen@gmx.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:06:50 -07:00
Markus Stockhausen
fcce51bfd4 net: mdio: realtek-rtl9300: use command runner for read_c45()
Convert the read_c45() path to the new command runner. This needs the
additional helper otto_emdio_read_cmd() that can issue the command runner
and process a read operation. It is basically nothing more than

- run the command
- read the command result thorugh the I/O register

With this in place convert the read_c45() like the alread existing write
C22/C45 implementation.

- bus calls otto_emdio_read_c45()
- this handed over to SoC specific otto_emdio_9300_read_c45()
- the registers are filled
- the otto_emdio_read_cmd() is issued
- that calls the command runner

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260527163449.1294961-4-markus.stockhausen@gmx.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:06:50 -07:00
Markus Stockhausen
9cd59932f2 net: mdio: realtek-rtl9300: use command runner for write_c22()
Now that the driver has a generic command runner make use of it in the
write_c22() path. For this.

- add generic otto_emdio_write_c22() helper that will be called by bus
- convert otto_emdio_9300_write_c22() to new command runner logic

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260527163449.1294961-3-markus.stockhausen@gmx.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:06:49 -07:00
Markus Stockhausen
9ccb438210 net: mdio: realtek-rtl9300: provide generic command runner
The current bus read/write commands for C22/C45 are RTL930x specific.
Avoid to duplicate those 200 lines of code for the RTL838x, RTL839x and
RTL931x targets. Instead provide a generic command runner that is SoC
independent. The implementation works as follows:

The runner will take a prepared list of the four MDIO registers. It will
feed the data into the registers. This generic write to all registers
(or to say "a little bit too much") is no issue. The hardware looks at
the to be executed command and will only take the pieces of data that
are really required. No side effects have been observed on any of the
four SoCs during the time this mechanism exists in downstream OpenWrt.

The last fed register is the C22/command register. This will be enriched
with the proper command flags from the caller. The hardware issues the
command and the runner will wait for its finalization.

Besides from feeding all registers the runner emulates the behaviour of
the old code as best as possible

- check defensively for a running command in advance
- Before this commit the driver had different MMIO timeout values.
  1000s for command preparation, 100us after writes and 1000us after
  reads. The new version uses a consistent 1000us timeout for all
  of these.
- return -ENXIO in case of hardware failure (fail bit)

As a first consumer of this runner convert the write_c45() function.
This is realized in a multi stage approach

- a generic otto_emdio_write_c45() will be called by the bus
- this will forward the request to the device specific writer. In this
  case otto_emdio_9300_write_c45().
- There the command data is filled in and the additional helper
  otto_emdio_write_cmd() will be called
- That adds the write flag and issues the generic command runner.

With all the above mentioned in place, there is not much left to do in
otto_emdio_9300_write_c45(). It just fills the register fields and
calls the write helper with the right command bits.

Signed-off-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260527163449.1294961-2-markus.stockhausen@gmx.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-01 19:06:49 -07:00
Chanwoo Lee
0600eec09a scsi: ufs: Remove redundant vops NULL check and trivial wrapper
ufshcd_variant_hba_init/exit() check 'if (!hba->vops)' before calling
vops wrappers, but the wrappers already do NULL check internally. Remove
the redundant checks. Also remove ufshcd_variant_hba_exit() entirely
since it only wraps ufshcd_vops_exit() with no added value.

Signed-off-by: Chanwoo Lee <cw9316.lee@samsung.com>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20260529061623.301291-1-cw9316.lee@samsung.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-06-01 22:01:54 -04:00
Chanwoo Lee
6bfc4bfd04 scsi: ufs: Remove unnecessary return in void vops wrappers
ufshcd_vops_exit(), ufshcd_vops_setup_task_mgmt(), and
ufshcd_vops_hibern8_notify() use 'return hba->vops->xxx()' while other
void vops wrappers call without return.  Remove the unnecessary return
keywords for consistency.

Signed-off-by: Chanwoo Lee <cw9316.lee@samsung.com>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20260529061503.301182-1-cw9316.lee@samsung.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-06-01 21:59:51 -04:00
Chanwoo Lee
2483ae0a56 scsi: ufs: Fix wrong value printed in unexpected UPIU response case
In ufshcd_transfer_rsp_status(), the default case of the inner switch
statement prints the UPIU response code when an unexpected response is
received. However, the code was printing 'result' variable which is
always 0 at that point, making the error message useless for debugging.

Fix this by printing the actual UPIU response code returned by
ufshcd_get_req_rsp().

Fixes: 08108d3112 ("scsi: ufs: Improve type safety")
Signed-off-by: Chanwoo Lee <cw9316.lee@samsung.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20260527092134.275887-1-cw9316.lee@samsung.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-06-01 21:59:00 -04:00
Chanwoo Lee
4cf752f6b9 scsi: ufs: core: Fix NULL pointer dereference in scsi_cmd_priv() calls
ufshcd_tag_to_cmd() may return NULL if no command is associated with the
given tag. However, several callers dereference the returned cmd pointer
via scsi_cmd_priv() without checking for NULL first, leading to a
potential NULL pointer dereference.

Fix this by adding NULL checks for cmd before calling scsi_cmd_priv()
and moving the lrbp initialization after the NULL check.

Signed-off-by: Chanwoo Lee <cw9316.lee@samsung.com>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20260529010739.295391-1-cw9316.lee@samsung.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-06-01 21:57:52 -04:00
Arnd Bergmann
c39a9a02bc scsi: megaraid_mbox: Avoid double kfree()
Smatch found a double-free after my recent change:

	drivers/scsi/megaraid/megaraid_mbox.c:3474 megaraid_cmm_register()
	error: double free of 'adp' (line 3468)

Since the object is no longer allocated in megaraid_cmm_register(),
remove the kfree() as well.

Fixes: c1f7275b61 ("scsi: megaraid_mbox: Reduce stack usage in megaraid_cmm_register()")
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260601210216.846809-1-arnd@kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-06-01 21:55:19 -04:00
Dan Carpenter
1b6f03b7ae scsi: pm8001: Fix error code in non_fatal_log_show()
The non_fatal_log_show() function is supposed to return negative error
codes on failure.  But because the error codes are saved in a u32 and
then cast to signed long, they end up being high positive values instead
of negative.  Remove the intermediary u32 variable to fix this bug.

Fixes: dba2cc03b9 ("scsi: pm80xx: sysfs attribute for non fatal dump")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://patch.msgid.link/ahs-bEsBJH0KhnsX@stanley.mountain
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-06-01 21:52:12 -04:00
Rosen Penev
056fca1f27 scsi: lpfc: Turn lpfc_queue q_pgs into a flexible array
The q_pgs pointer was assigned to point at the trailing memory allocated
past the struct. Convert it to a proper C99 flexible array member and
use struct_size() for the allocation.

Assisted-by: Claude:Opus-4.7
Signed-off-by: Rosen Penev <rosenp@gmail.com>
Reviewed-by: Justin Tee <justin.tee@broadcom.com>
Link: https://patch.msgid.link/20260523050241.190239-1-rosenp@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-06-01 21:46:50 -04:00
Daejun Park
06a34d9c1f scsi: ufs: core: Skip link param validation when lanes_per_direction is unset
ufshcd_validate_link_params(), added by commit e72323f3b0 ("scsi: ufs:
core: Configure only active lanes during link"), is called
unconditionally from ufshcd_link_startup() and fails link startup with
-ENOLINK when the connected lane count read from the device differs from
hba->lanes_per_direction.

lanes_per_direction is only set by ufshcd-pltfrm (default 2, or the
"lanes-per-direction" devicetree property); ufshcd-pci controllers
(e.g. Intel) leave it 0. As the device always reports >= 1 connected
lanes, the check can never match and link startup always fails.
Reproduced with QEMU's UFS device.

Skip the check when lanes_per_direction is unset: with no expected value
to validate against, restore the behaviour from before that commit.

Fixes: e72323f3b0 ("scsi: ufs: core: Configure only active lanes during link")
Signed-off-by: Daejun Park <daejun7.park@samsung.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://patch.msgid.link/20260520070009epcms2p6542f3abb7660839e9d8140b3f2f145c3@epcms2p6
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-06-01 21:44:21 -04:00
Alexei Starovoitov
51321158a3 Merge branch 'minimize-annotations-for-arena-programs'
Emil Tsalapatis says:

====================
Minimize annotations for arena programs

BPF programs must currently include code to address two limitations
of function signatures that include arena types. First, arena arguments
must be annotated with __arg_arena in the function signature in addition
to __arena. Second, it is currently not allowed to return an arena pointer
from a subprog, even though it is safe to do so. These limitations require
extra annotations and typecasts respectively, and have proven sources of
confusion to programmers.

The patchset improves arena-related function signatures in two ways.
First, it removes the need for __arg_arena in function signatures.
Second, it allows subprogs to directly return arena pointers to their
caller.

To do this we add a new type tag to the existing __arena annotation.
The annotation is currently an alias for __attribute__((address_space(1))),
which is not discoverable from BTF alone and so cannot be used to
determine whether a pointer variable is an arena pointer during
verification. With the new type tag, we can determine whether
either the arguments and or the return value of a function belong
in an arena.

We test the new code by modifying libarena to take advantage of these
relaxed limitations.

CHANGELOG
=========

v2 -> v3 (https://lore.kernel.org/bpf/20260530002259.4505-1-emil@etsalapatis.com/)

- Added Acks by Eduard
- Complete the __arg_arena removal by removing them from htab (Alexei)
- Add a test in verifier_arena_globals1.c to confirm the new __arena attribute
works as expected in function argument and return types
- Reject type tags on non-pointer types, currently only possible in handcrafted
  BTF (Eduard)
- Undo inaccurate change on verifier comment (AI)
- Fix error return value for invalid BTF return types during BTF parsing (Eduard)

v1 -> v2 (lore.kernel.org/bpf/20260527071457.4598-1-emil@etsalapatis.com/)

- Rebased to fix conflict
- Removed the typedef foo * foo_t typedefs. Those were necessary to avoid
annotating each instance of the type with __arena. The new version of the
patch instead removes typedefs and uses __arena everywhere directly (see
patch 4/5 for more details).
- Reorganized the patchset to frontload all kernel-side changes and place
the libarena changes at the end.
====================

Link: https://patch.msgid.link/20260602004120.17087-1-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:42:34 -07:00
Emil Tsalapatis
9fd5bf96ac selftests/bpf: Add tests for the new type-tag based __arena identifier
Add selftests that combine the new type-based __arena identifier with
the volatile qualifier both in functions' arguments and return values.
This way we test both that they are recognized as arena arguments and
that they are not sensitive to the position they are placed in the type
compared to other qualifiers.

Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260602004120.17087-7-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:42:34 -07:00
Emil Tsalapatis
367e6e4a81 selftests/bpf: libarena: Directly return arena pointers from functions
Now that the __arena annotation includes a BTF type tag, and the
verifier can identify arena pointers at BTF loading time, return
arena pointers as their true type instead of casting to u64. Remove the
preprocessor typecast wrappers used to hide this from the caller.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260602004120.17087-6-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:42:33 -07:00
Emil Tsalapatis
b9b23fe176 selftests/bpf: Remove __arg_arena from the codebase
Now that BPF __arg_arena has been subsumed by __arena, remove
__arg_arena from the codebase. This way the user has one fewer
annotation to worry about.

To remove __arg_arena we remove the typedefs we were previously
using to minimize __arena annotations. This is because __arena
now also includes a BTF type tag, which is ignored for non-pointer
types. As a result, we cannot capture the whole __arena annotation
inside a typedef and need to directly annotate the pointer type when
declaring the variable.

The extra verbosity is worth it because the use of the __arena tag
is intuitive to the programmer and removes the __arg_arena tag that
has been a consistent source of confusion for users. The typedefs
can be reintroduced later (without __arg_arena) once compilers start
supporting BTF type tags for non-pointer types.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260602004120.17087-5-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:42:33 -07:00
Emil Tsalapatis
3e924e9272 bpf: Allow subprogs to return arena pointers
BPF subprogs currently only return void or scalar values. However,
it is also safe to return arena pointers between subprogs in the same
BPF program: Arena pointers are guaranteed to be safe for both programs
at any point. Expand the verifier to permit returning an arena pointer
to the caller.

The main subprog is still not allowed to return an arena pointer because
arena pointers are internal to the BPF program, and the return values
permitted for each main subprog depend on the program type anyway.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260602004120.17087-4-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:42:33 -07:00
Emil Tsalapatis
5ab4bc67d8 verifier: parse BTF type tags for function arguments
The BTF parsing logic for function arguments goes through
the arguments' decl tags, but does not go into their type
tags. Add type tag parsing for function arguments.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260602004120.17087-3-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:42:33 -07:00
Emil Tsalapatis
a0fa68d8ce selftests/bpf: libarena: Add "arena" BTF type tag to __arena qualifier
The arena qualifier currently designates its associated type
as belonging to address space 1. This property affects code
generation, but is not reflected in the BTF information of
the function.

This lack of information at the BTF level prevents us from
returning arena pointers from global subprograms. Subprogs
cannot return any data structure more complex than a scalar,
so pointers to structs are rejected as a return type. We
have no way of marking the return type as a pointer to an
arena, which is safe provided the two subprogs have the same
arena.

Expand the __arena qualifier to also attach a BTF type tag
to the type. This lets us determine whether a variable belongs
to an arena from its type alone through BTF parsing.

Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260602004120.17087-2-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:42:33 -07:00
Ionut Nechita
be8fcd4a82 scsi: sas: Skip opt_sectors when DMA reports no real optimization hint
sas_host_setup() unconditionally sets shost->opt_sectors from
dma_opt_mapping_size().

When the IOMMU is disabled or in passthrough mode and no DMA ops provide
an opt_mapping_size callback, dma_opt_mapping_size() returns
min(dma_max_mapping_size(), SIZE_MAX) which equals
dma_max_mapping_size() — a hard upper bound, not an optimization hint.

On a Dell PowerEdge R750 with mpt3sas (Broadcom SAS3816, FW 33.15.00.00)
and intel_iommu=off the following values are observed:

  dma_opt_mapping_size()  = dma_max_mapping_size() (no real hint)
  shost->max_sectors      = 32767
  opt_sectors             = min(32767, huge >> 9) = 32767
  optimal_io_size         = 32767 << 9 = 16776704
                          → round_down(16776704, 4096) = 16773120

The SAS disk (SAMSUNG MZILT800HBHQ0D3) does not report an Optimal
Transfer Length in VPD page B0, so sdkp->opt_xfer_blocks remains 0.

sd_revalidate_disk() then uses min_not_zero(0, opt_sectors) =
opt_sectors, propagating the bogus value into the block device's
optimal_io_size (visible as OPT-IO = 16773120 in lsblk --topology).

mkfs.xfs picks up optimal_io_size and minimum_io_size and computes:

  swidth = 16773120 / 4096 = 4095
  sunit  = 8192 / 4096     = 2

Since 4095 % 2 != 0, XFS rejects the geometry:

  SB stripe unit sanity check failed

This makes it impossible to create XFS filesystems (e.g. for
/var/lib/docker) during system bootstrap.

Fix this by introducing a sas_dma_setup_opt_sectors() helper that sets
opt_sectors only when dma_opt_mapping_size() is strictly less than
dma_max_mapping_size(), indicating a genuine DMA optimization
constraint.

The helper computes min(opt_sectors, max_sectors) first, then rounds
down to a power of two so that filesystem geometry calculations always
produce clean results.

When the two DMA values are equal, no backend provided a real hint, so
opt_sectors stays at 0 ("no preference").

[mkp: implemented hch's suggestion]

Fixes: 4cbfca5f77 ("scsi: scsi_transport_sas: cap shost opt_sectors according to DMA optimal limit")
Cc: stable@vger.kernel.org
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Ionut Nechita <ionut.nechita@windriver.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://patch.msgid.link/20260519135238.373784-2-ionut.nechita@windriver.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-06-01 21:42:09 -04:00
Alexei Starovoitov
b6aa0abf9f Merge branch 'more-gen_loader-fixes'
Daniel Borkmann says:

====================
More gen_loader fixes

Follow-up fixes for the signed loader, includes also the recent
sashiko findings.

v1->v2:
  - Fixed up verifier_map_ptr selftest
  - Added patch 1/2/6/7 with a new map-in-map fix and a
    redundant hash_buf memcpy cleanup as well as selftests
====================

Link: https://patch.msgid.link/20260601150248.394863-1-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:36:41 -07:00
Daniel Borkmann
32f725458a selftests/bpf: Test that exclusive maps are rejected in map-in-map
Add a subtest to map_excl that verifies an exclusive map (created with
excl_prog_hash) cannot be used in a map-of-maps, covering both kernel
enforcement points: i) the inner-map template at map-of-maps creation
and, ii) the element inserted into an existing map-of-maps.

  # LDLIBS=-static PKG_CONFIG='pkg-config --static' ./vmtest.sh -- ./test_progs -t map_excl
  ./test_progs -t map_excl
  [    1.728106] bpf_testmod: loading out-of-tree module taints kernel.
  [    1.730473] bpf_testmod: module verification failed: signature and/or required key missing - tainting kernel
  #215/1   map_excl/map_excl_allowed:OK
  #215/2   map_excl/map_excl_denied:OK
  #215/3   map_excl/map_excl_no_map_in_map:OK
  #215     map_excl:OK
  Summary: 1/3 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20260601150248.394863-8-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:36:41 -07:00
KP Singh
38498c0eba selftests/bpf: Adjust verifier_map_ptr for the map's excl field
Adding the u32 excl field at offset 32 of struct bpf_map right after the
sha[SHA256_DIGEST_SIZE] hash shifts the ops pointer from offset 32 to 40.
Therefore, fix up the test case.

  # LDLIBS=-static PKG_CONFIG='pkg-config --static' ./vmtest.sh -- ./test_progs -t verifier_map_ptr
  [...]
  #637/1   verifier_map_ptr/bpf_map_ptr: read with negative offset rejected:OK
  #637/2   verifier_map_ptr/bpf_map_ptr: read with negative offset rejected @unpriv:OK
  #637/3   verifier_map_ptr/bpf_map_ptr: write rejected:OK
  #637/4   verifier_map_ptr/bpf_map_ptr: write rejected @unpriv:OK
  #637/5   verifier_map_ptr/bpf_map_ptr: read non-existent field rejected:OK
  #637/6   verifier_map_ptr/bpf_map_ptr: read non-existent field rejected @unpriv:OK
  #637/7   verifier_map_ptr/bpf_map_ptr: read ops field accepted:OK
  #637/8   verifier_map_ptr/bpf_map_ptr: read ops field accepted @unpriv:OK
  [...]
  Summary: 2/18 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: KP Singh <kpsingh@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20260601150248.394863-7-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:36:40 -07:00
Daniel Borkmann
60214435b3 libbpf: Skip max_entries override on signed loaders
bpf_gen__map_create() lets the host-supplied loader ctx override a
map's max_entries at runtime (map_desc[idx].max_entries, when non-zero).
This is how the light skeleton sizes maps to the target machine, but
it happens after emit_signature_match() and is covered by neither the
signed loader instructions nor the hashed blob.

For a signed loader this means an untrusted host can re-dimension the
program's maps, outside what the signature attests to. Gate the override
on gen_hash so signed loaders use the signer-provided max_entries baked
into the blob.

Fixes: ea923080c1 ("libbpf: Embed and verify the metadata hash in the loader")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20260601150248.394863-6-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:36:40 -07:00
Daniel Borkmann
61e0841523 libbpf: Skip initial_value override on signed loaders
bpf_gen__map_update_elem() emits code that, when the host-supplied
loader ctx provides a non-NULL map_desc[idx].initial_value, overwrites
the blob value with bytes read from the host (bpf_copy_from_user /
bpf_probe_read_kernel) before the BPF_MAP_UPDATE_ELEM that populates
the program's .data/.rodata/.bss maps.

This override runs after emit_signature_match() has validated map->sha[],
and initial_value is part of neither the signed loader instructions nor
the hashed data blob. For a signed loader this lets an untrusted host
substitute global-variable contents into a program whose code carries
a valid signature, thus weakening what the signature attests to.

The blob already contains the signer-provided value (added via add_data()
and covered by the embedded, signed hash), so simply skip emitting the
override for signed loaders (gen_hash). Runtime initialization stays
available for the unsigned light-skeleton path as before. The jump
offsets within the override block are internal to it, so guarding the
whole block leaves them unchanged.

Fixes: ea923080c1 ("libbpf: Embed and verify the metadata hash in the loader")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20260601150248.394863-5-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:36:40 -07:00
KP Singh
0fb6c9ed64 libbpf: Reject non-exclusive metadata maps in the signed loader
The loader verifies map->sha against the metadata hash in its
instructions. map->sha is calculated when BPF_OBJ_GET_INFO_BY_FD is
called on the frozen map.

While the map is frozen, the /signed loader/ must also ensure the map
is exclusive, as, without exclusivity (which a hostile host could just
omit when loading the loader), another BPF program with map access can
mutate the contents afterwards, so the check passes on stale data.

With the extra check as part of the signed loader, it now refuses to
move on with map->sha validation if the host set it up wrongly.

Fixes: fb2b0e2901 ("libbpf: Update light skeleton for signing")
Signed-off-by: KP Singh <kpsingh@kernel.org>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20260601150248.394863-4-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:36:40 -07:00
Daniel Borkmann
c48c3a7e7d bpf: Drop redundant hash_buf from map_get_hash operation
bpf_map_get_info_by_fd() is the only caller of the ->map_get_hash
and always invokes it with hash_buf == map->sha and hash_buf_size
of SHA256_DIGEST_SIZE. array_map_get_hash() in turn lets sha256()
write the digest directly into that buffer (map->sha) and then
performs a trailing memcpy(), which evaluates to memcpy(map->sha,
map->sha, 32): a redundant self-copy. The hash_buf_size argument
was never used at all. Simplify this a bit, no functional change.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20260601150248.394863-3-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:36:40 -07:00
Daniel Borkmann
9a3c3c49c3 bpf: Reject exclusive maps as inner maps in map-in-map
An exclusive map (created with excl_prog_hash) is bound to a single
program by hash: check_map_prog_compatibility() refuses to load any
program whose digest does not match map->excl_prog_sha. That check
only runs for maps a program references directly, i.e. its used_maps.
A map reached at runtime through a map-of-maps is never in used_maps,
and bpf_map_meta_equal() does not consider excl_prog_sha, so an
exclusive map can be inserted into a non-exclusive outer map and
then looked up and mutated by an unrelated program, bypassing the
exclusivity guarantee.

For the signed loader this defeats the metadata map exclusivity check
added in the signed loader: the cached map->sha[] is validated against
the signed hash while another program on a hostile host rewrites the
frozen map's contents through the outer map.

Fixes: baefdbdf68 ("bpf: Implement exclusive map creation")
Reported-by: sashiko <sashiko@sashiko.dev>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20260601150248.394863-2-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:36:40 -07:00
Alexei Starovoitov
3d781fffdc Merge branch 'refactor-verifier-object-relationship-tracking'
Amery Hung says:

====================
Refactor verifier object relationship tracking

Hi all,

This patchset cleans up dynptr handling, refactors object relationship
tracking in the verifier by introducing parent_id and folding ref_obj_id
into id, and fixes dynptr use-after-free bugs where file/skb dynptrs
are not invalidated when the parent referenced object is freed.

* Motivation *

In BPF qdisc programs, an skb can be freed through kfuncs. However,
since dynptr does not track the parent referenced object (e.g., skb),
the verifier does not invalidate the dynptr after the skb is freed,
resulting in use-after-free. The same issue also affects file dynptr.

The figure below shows the current state of object tracking. The
verifier tracks objects using three fields: id for nullness tracking,
ref_obj_id for lifetime tracking, and dynptr_id for tracking the parent
dynptr of a slice (PTR_TO_MEM only). While dynptr_id links slices to
their parent dynptr, there is no field that links a dynptr back to its
parent skb. When the skb is freed via release_reference(ref_obj_id=1),
only objects with ref_obj_id=1 are invalidated. Since skb dynptr is
non-referenced (ref_obj_id=0), the dynptr and its derived slices remain
accessible.

Current: object (id, ref_obj_id, dynptr_id)
  id         = unique id of the object (for nullness tracking)
  ref_obj_id = id of the referenced object (for lifetime tracking)
  dynptr_id  = id of the parent dynptr (only for PTR_TO_MEM slices)

                      skb (0,1,0)
                             ^^
                          ! No link from dynptr to skb !
                             |+------------------------------+
                             |           bpf_dynptr_clone    |
                 dynptr A (2,0,0)                dynptr C (4,0,0)
                           ^                               ^
        bpf_dynptr_slice   |                               |
                           |                               |
              slice B (3,0,2)                 slice D (5,0,4)

* Why not simply use ref_obj_id to track the parent? *

A natural first approach is to link dynptr to its parent by sharing
the parent's ref_obj_id and propagating it to slices. Now, releasing
the skb via release_reference(ref_obj_id=1) correctly invalidates all
derived objects.

Attempted fix: share parent's ref_obj_id

                      skb (0,1,0)
                             ^^
                             ||
                             |+------------------------------+
                             |           bpf_dynptr_clone    |
                 dynptr A (2,1,0)                dynptr C (4,1,0)
                           ^                               ^
        bpf_dynptr_slice   |                               |
                           |                               |
              slice B (3,1,2)                 slice D (5,1,4)

However, this approach does not generalize to all dynptr types.
Referenced dynptrs such as file dynptr acquire their own ref_obj_id to
track the dynptr's lifetime. Since ref_obj_id is already used for the
dynptr's own reference, it cannot also be used to point to the parent
file object. While it is possible to add specialized handling for
individual dynptr types [0], it adds complexity and does not generalize.

An alternative approach is to avoid introducing a new field and instead
repurpose ref_obj_id as parent_id by folding lifetime tracking into id
[1]. In this design, each object is represented as (id, ref_obj_id)
where id is used for both nullness and lifetime tracking, and ref_obj_id
tracks the parent object's id.

Attempted: object (id, ref_obj_id)
  id         = id of the object (for nullness and lifetime tracking)
  ref_obj_id = id of the parent object
  '          = id is referenced

                        skb (1',0)
                             ^^
                             ||
        bpf_dynptr_from_skb  |+------------------------------+
                             |      bpf_dynptr_clone(A, C)   |
                 dynptr A (2,1')                 dynptr C (4,1')
                           ^                               ^
        bpf_dynptr_slice   |                               |
                           |                               |
                slice B (3,2)                   slice D (5,4)

However, this design cannot express the relationship between referenced
socket pointers and their casted counterparts. After pointer casting,
the original and casted pointers need the same lifetime (same ref_obj_id
in the current design) but different nullness (different id). The casted
pointer may be NULL even if the original is valid. With id serving as
the only field for both nullness and lifetime, and ref_obj_id repurposed
as parent, there is no way to express "different identity, same
lifetime."

Referenced socket pointer (expressed using current design):

                                C = ptr_casting_function(A)
                ptr A (1,1,0)                     ptr C (2,1,0)
                         ^                                 ^
                         |                                 |
                        ptr C may be NULL even if ptr A is valid
                        but they have the same lifetime

* New Design: parent_id with branch splitting and intermediate reference *

The patchset folds ref_obj_id into id and adds parent_id to
bpf_reg_state (patch 5). A child object's parent_id points to the
parent object's id. This replaces the PTR_TO_MEM-specific dynptr_id.
Whether a register is referenced is determined by checking if its id
appears in the reference array via reg_is_referenced() rather than
reading a dedicated ref_obj_id field.

Pointer casting:

The challenge with pointer casting is that a cast result may be NULL
even when the source is valid, requiring distinct identity but shared
lifetime. This is solved using branch splitting: when a helper like
bpf_sk_fullsock() is called with a referenced pointer, the verifier
pushes an explicit NULL branch and assigns the cast result the same id
as the source. Since the cast may return NULL for a non-NULL input, the
NULL case is explored as a separate verifier branch. This allows
releasing any of the original or cast pointers to invalidate all others,
while avoiding the need for a separate tracking mechanism.

Referenced dynptrs:

The challenge with referenced dynptrs is that clones of a referenced
dynptr have the same lifetime but different identities. When a
referenced dynptr is overwritten, only slices derived from it will be
invalidated. To solve this, the verifier creates an intermediate
reference. This reference serves as a shared lifetime anchor for the
dynptr and all its clones. All clones share the same parent_id but get
unique ids for independent slice tracking. Releasing a referenced dynptr
releases the intermediate reference, which in turn invalidates all
clones and their derived slices. If the parent object is released while
the intermediate reference still exists, it is reported as a leaked
reference.

Release cascading:

When releasing an object, release_reference() performs a stack-based DFS
to invalidate all descendants. It walks the object tree via parent_id
links, invalidating registers and dynptr stack slots. Child references
encountered during traversal are reported as leaked references.

parent_id is also added to bpf_reference_state to enable intermediate
reference. When acquiring a reference, a parent_id can be specified to
link the new reference to an existing one (e.g., file dynptr's
intermediate reference has parent_id linking to the file's reference).

Final: object (id, parent_id)
  id        = unique id of the object (for nullness and lifetime
              tracking)
  parent_id = id of the parent object (for object relationship
              tracking)
  I         = intermediate reference serving as lifetime anchor in
              acquired_refs
  '         = id is referenced (appears in reference array)

                          skb (1',0)
                               ^^
                               ||
          bpf_dynptr_from_skb  |+------------------------------+
                               |      bpf_dynptr_clone(A, C)   |
                   dynptr A (2,1')                 dynptr C (4,1')
                             ^                               ^
          bpf_dynptr_slice   |                               |
                             |                               |
                  slice B (3,2)                   slice D (5,4)

* Preserving reg->id after null-check *

For parent_id tracking to work, child objects need to refer to the
parent's id. This requires two preparatory changes: assigning reg->id
when reading referenced kptrs from program context (patch 3), and
preserving reg->id of pointer objects after null-check (patch 4).
Previously, null-check would clear reg->id, making it impossible for
children to reference the parent afterward. The latter causes a slight
increase in verified states for some programs. One selftest object
sees +19 states (+5.01%). For Meta BPF objects, the increase is
also minor, with the largest being +34 states (+3.63%).

* Object relationship in different scenarios (for reference) *

The figures below show how the final design handles all four
combinations of referenced/non-referenced dynptr with
referenced/non-referenced parent.

(1) Non-referenced dynptr with referenced parent (e.g., skb in Qdisc):

                          skb (1',0)
                               ^^
                               ||
          bpf_dynptr_from_skb  |+------------------------------+
                               |      bpf_dynptr_clone(A, C)   |
                   dynptr A (2,1')                 dynptr C (4,1')

                         dynptr A and C live independently

(2) Non-referenced dynptr with non-referenced parent (e.g., skb in TC,
    always valid):

      bpf_dynptr_from_skb
                                  bpf_dynptr_clone(A, C)
             dynptr A (1,0)                    dynptr C (2,0)

                         dynptr A and C live independently

(3) Referenced dynptr with referenced parent:

                     file (1',0)
                           ^
     bpf_dynptr_from_file  |
                     I (2',1')  <-- intermediate reference
                        ^^
                        ||
                        |+-------------------------------+
                        |       bpf_dynptr_clone(A, C)   |
            dynptr A (3,2')                  dynptr C (4,2')

                        dynptr A and C have the same lifetime

  Releasing either dynptr releases I, invalidating both.
  Releasing file (1') detects I as a leaked reference.

(4) Referenced dynptr with non-referenced parent:

 bpf_ringbuf_reserve_dynptr
                     I (1',0)  <-- intermediate reference
                        ^^
                        ||
                        |+--------------------------------+
                        |       bpf_dynptr_clone(A, C)    |
            dynptr A (2,1')                   dynptr C (3,1')

                      dynptr A and C have the same lifetime

[0] https://lore.kernel.org/bpf/20250414161443.1146103-2-memxor@gmail.com/
[1] https://github.com/ameryhung/bpf/commits/obj_relationship_v2_no_parent_id/

Changelog:

v5 -> v6
  - Squash "bpf: Fold ref_obj_id into id and introduce virtual references"
    (v5 patch 9) into "bpf: Refactor object relationship tracking and
    fix dynptr UAF bug" (now patch 5). ref_obj_id is removed in the same
    patch that introduces parent_id, eliminating the intermediate state
    where both coexist (Eduard)
  - Drop virtual references for pointer casting. Instead, cast results
    reuse the source pointer's id and use branch splitting to explore
    the NULL case as a separate verifier branch. This avoids adding
    virtual reference infrastructure for a case that can be handled more
    simply (Eduard, Andrii)
  - Address nit from Eduard
  Link: https://lore.kernel.org/bpf/20260519181314.2731658-1-ameryhung@gmail.com/

v4 -> v5
  - Add patch 9 folding ref_obj_id into id and introducing virtual
    references for pointer casting and referenced dynptr clones (Eduard, Andrii)
  - Add patch 10 fixing dynptr ref counting to scan all call frames
    instead of only the current frame (Eduard)
  - Add utility function validate_ref_obj() (Eduard)
  Link: https://lore.kernel.org/bpf/20260506142709.2298255-1-ameryhung@gmail.com/

v3 -> v4
  - Add patch 1 clean up mark_stack_slot_obj_read() and callers
    (to address v3 ignoring err returned from mark_dynptr_read) (Andrii)
  - Fix release_reference() and move the logic allowing destroying a
    referenced object when refcnt > 1 from
    destroy_if_stack_slots_dynptr() to release_reference() (Mykyta)
  - Add patch 7 introducing ref_obj_desc and unifying ref_obj handling
    (to address Eduard's concern about unclear meta->{id,ref_obj_id}
    initialization/use and confusing function arguments of
    process_dynptr_func())
  - Add patch 8 unifying release_regno handling so that bpf_kptr_xchg
    also use release_reference()
  Link: https://lore.kernel.org/bpf/20260421221016.2967924-1-ameryhung@gmail.com/

v2 -> v3
  - Rebase to bpf-next/master
  - Update veristat numbers
  - Update commit msg to explain multiple dropped checks (Mykyta, Andrii)
  - Reuse idmap as idstack in release_reference() and check for
    duplicate id (Mykyta, Andrii)
  - Change to use RUN_TEST for qdisc dynptr selftest (Eduard)
  Link: https://lore.kernel.org/bpf/20260307064439.3247440-1-ameryhung@gmail.com/

v1 -> v2
  - Redesign: Use object (id, ref_obj_id, parent_id) instead of
    (id, ref_obj_id) as it cannot express ptr casting without
    introducing specialized code to handle the case
  - Use stack-based DFS to release objects to avoid recursion (Andrii)
  - Keep reg->id after null check
  - Add dynptr cleanup
  - Fix dynptr kfunc arg type determination
  - Add a file dynptr UAF selftest
  Link: https://lore.kernel.org/bpf/20260202214817.2853236-1-ameryhung@gmail.com/
---
====================

Link: https://patch.msgid.link/20260529014936.2811085-1-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:31:43 -07:00
Amery Hung
60c7c3b880 selftests/bpf: Test using dynptr after freeing the underlying object
Make sure the verifier invalidates the dynptr and dynptr slice derived
from an skb after the skb is freed.

Signed-off-by: Amery Hung <ameryhung@gmail.com>
Link: https://lore.kernel.org/r/20260529014936.2811085-14-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:31:42 -07:00
Amery Hung
3f75a757a3 selftests/bpf: Test using file dynptr after the reference on file is dropped
File dynptr and slice should be invalidated when the parent file's
reference is dropped in the program. Without the verifier tracking
dyntpr's parent referenced object, the dynptr would continute to be
incorrectly used even if the underlying file is being tear down or gone.

Signed-off-by: Amery Hung <ameryhung@gmail.com>
Link: https://lore.kernel.org/r/20260529014936.2811085-13-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:31:42 -07:00
Amery Hung
925320666e selftests/bpf: Test using slice after invalidating dynptr clone
The parent object of a cloned dynptr is skb not the original dynptr.
Invalidate the original dynptr should not prevent the program from
using the slice derived from the cloned dynptr.

Signed-off-by: Amery Hung <ameryhung@gmail.com>
Link: https://lore.kernel.org/r/20260529014936.2811085-12-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:31:42 -07:00
Amery Hung
fbcc68af60 selftests/bpf: Test creating dynptr from dynptr data and slice
The verifier currently does not allow creating dynptr from dynptr data
or slice. Add a selftest to test this explicitly.

Signed-off-by: Amery Hung <ameryhung@gmail.com>
Link: https://lore.kernel.org/r/20260529014936.2811085-11-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:31:42 -07:00
Amery Hung
2eee6fe8ac bpf: Fix dynptr ref counting to scan all call frames
When checking whether a referenced dynptr can be overwritten,
destroy_if_dynptr_stack_slot only counted sibling dynptrs in the
current call frame. If a clone sharing the same virtual ref parent
existed in a different frame (e.g., passed to a subprog), it would
not be counted, causing the verifier to incorrectly reject the
overwrite with "cannot overwrite referenced dynptr".

Fix by extracting the counting into dynptr_ref_cnt() which uses
bpf_for_each_reg_in_vstate_mask() to scan dynptr stack slots across
all call frames.

Fixes: 017f5c4ef7 ("bpf: Allow overwriting referenced dynptr when refcnt > 1")
Reported-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Link: https://lore.kernel.org/r/20260529014936.2811085-10-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:31:41 -07:00
Amery Hung
bcfcb15fde bpf: Unify release handling for helpers and kfuncs
Introduce release_reg() to consolidate the release logic shared by both
helpers and kfuncs: dynptr release, kptr_xchg percpu-to-RCU conversion,
regular reference release, and NULL pass-through. NULL pass-through is
only allowed if the prototype indicates the argument may be null.

Determine release_regno from the function prototype/metadata before
argument checking, rather than discovering it dynamically during
argument processing. For helpers, scan the arg_type array in
check_func_proto() via check_proto_release_reg(). For kfuncs, set
release_regno to BPF_REG_1 in bpf_fetch_kfunc_arg_meta() when
KF_RELEASE is set. In the future when we start adding decl_tag to
kfunc arguments, we can just look at the function prototype instead
of a release_regno.

Extract ref_convert_alloc_rcu_protected() and
invalidate_rcu_protected_refs() to make it more clear what the code is
doing. For ref_convert_alloc_rcu_protected(), it pre-converts
MEM_ALLOC | MEM_PERCPU registers to MEM_RCU (clearing id so they
survive), then calls release_reference() to invalidate the remaining
registers and release the reference state.

Add KF_RELEASE to bpf_dynptr_file_discard() so its release_regno is set
via fetch_kfunc_meta rather than being assigned manually in the dynptr
argument processing. Set arg_type to ARG_PTR_TO_DYNPTR for
KF_ARG_PTR_TO_DYNPTR so that check_func_arg_reg_off() correctly allows
non-zero stack offsets for dynptr release arguments same as helper.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Link: https://lore.kernel.org/r/20260529014936.2811085-9-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:31:41 -07:00
Amery Hung
b7dd2b3886 bpf: Unify referenced object tracking in verifier
Helpers and kfuncs independently tracked referenced object metadata
using standalone id fields in their respective arg_meta structs.
This led to duplicated logic and inconsistent error handling between the
two paths.

Introduce struct ref_obj_desc to consolidate id and parent_id along with
a count of how many arguments carry a reference. Add update_ref_obj() to
populate it from a bpf_reg_state, replacing open-coded assignments in
check_func_arg(), check_kfunc_args(), and process_iter_arg(). Add
validate_ref_obj() to check for ambiguous ref_obj before using it.

For ref_obj releasing helpers and kfuncs, keep checking it before
calling update_ref_obj() for now. A later patch will make these
functions not depending on ref_obj. For other users of ref_obj, move the
checks to the use locations. For helper, this means moving the checks
inside helper_multiple_ref_obj_use() to use locations.
is_acquire_function() is dropped as ref_obj is never used.

Pass ref_obj_desc into process_dynptr_func()/mark_stack_slots_dynptr()
instead of a bare parent_id to make it less confusing.

Drop the selftest introduced in 7ec899ac90 ("selftests/bpf: Negative
test case for ref_obj_id in args") since the verifier no longer
complains about ambiguous ref_obj if it is not used.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Link: https://lore.kernel.org/r/20260529014936.2811085-8-ameryhung@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-01 18:31:41 -07:00