Commit Graph

1464927 Commits

Author SHA1 Message Date
Doruk Tan Ozturk
55c68ac93e
nfc: llcp: bound the connect_sn TLV walk to the skb
Commit 27256cdb290e ("nfc: llcp: bound SNL TLV parsing to the skb and
add length checks") fixed the unbounded TLV walk in nfc_llcp_recv_snl(),
and commit d8bd2dedbde5 ("nfc: llcp: fix OOB read and u8 offset wrap in
TLV parsers") subsequently bounded nfc_llcp_parse_gb_tlv() and
nfc_llcp_parse_connection_tlv(). One sibling parser sharing the same
pattern remains unbounded: nfc_llcp_connect_sn().

nfc_llcp_connect_sn() walks a TLV list, reading a two-byte header
(type, length) followed by length bytes of value, without checking that
the two header bytes or the declared length stay within the buffer. It
returns a pointer to a service name of up to 255 bytes that may point
past the end of the skb; it is subsequently consumed by memcmp() in
nfc_llcp_sock_from_sn(). In addition tlv_array_len was computed as
"skb->len - LLCP_HEADER_SIZE" in size_t, so a CONNECT/CC frame shorter
than the LLCP header underflows to a huge length and the walk runs far
past the buffer.

nfc_llcp_connect_sn() is reachable from nfc_llcp_recv_connect() and
nfc_llcp_recv_cc(), i.e. from received CONNECT and CC PDUs. A nearby
NFC device can reach this without authentication; LLCP link activation
happens automatically after NFC-DEP, and the nfc_llcp_rx_skb()
dispatcher applies no minimum-length guard.

Walk the TLV list by pointer, bounded by skb_tail_pointer(skb), and
validate each declared length before use, matching the approach already
used for nfc_llcp_recv_snl(). Starting the walk at
&skb->data[LLCP_HEADER_SIZE] against the tail pointer also removes the
size_t underflow for short frames.

Found by 0sec automated security-research tooling (https://0sec.ai).

Fixes: d646960f79 ("NFC: Initial LLCP support")
Cc: stable@vger.kernel.org
Assisted-by: 0sec:claude-opus-4-8
Signed-off-by: Doruk Tan Ozturk <doruk@0sec.ai>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260709131229.44477-1-doruk@0sec.ai
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:03 +02:00
Doruk Tan Ozturk
95674f506c
nfc: llcp: reject PDUs shorter than the LLCP header
Every LLCP PDU begins with a two-byte header (DSAP/SSAP + PTYPE), but the
receive path never checked that a frame is at least LLCP_HEADER_SIZE bytes
before parsing it.

nfc_llcp_rx_skb() reads the header via nfc_llcp_ptype()/nfc_llcp_dsap()/
nfc_llcp_ssap(), which dereference pdu->data[0] and pdu->data[1], and a
CONNECT or CC PDU then computes

	tlv_array_len = skb->len - LLCP_HEADER_SIZE;

as a size_t and hands it to the TLV walk. When the frame is shorter than
the header the subtraction wraps to a huge value and the walk runs far
past the buffer, an out-of-bounds read.

A nearby NFC device can reach this without authentication; LLCP link
activation happens automatically after NFC-DEP.

Guard the common receive choke point __nfc_llcp_recv(), shared by both the
target (nfc_llcp_data_received()) and initiator (nfc_llcp_recv()) paths, so
a short skb is dropped before the rx_work worker parses it. Use
pskb_may_pull() rather than a skb->len test so the two header bytes are
guaranteed to sit in the skb linear area even for a non-linear skb,
matching how the sibling NCI and HCI receive paths validate their headers.

Reproduced with a KFENCE out-of-bounds read via /dev/virtual_nci on
linux-next.

Found by 0sec automated security-research tooling (https://0sec.ai).

Fixes: d646960f79 ("NFC: Initial LLCP support")
Cc: stable@vger.kernel.org
Suggested-by: David Laight <david.laight.linux@gmail.com>
Signed-off-by: Doruk Tan Ozturk <doruk@0sec.ai>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20260714164631.75068-1-doruk@0sec.ai
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:03 +02:00
Linmao Li
1c7dd70c0a
nfc: digital: Do not dump a NULL response in command completion
digital_wq_cmd_complete() dumps the response data whenever cmd->resp is
not an error pointer.  However, a driver can legitimately complete a
command with no response skb at all.

digital_tg_send_psl_res() is the only caller that passes timeout=0,
meaning no response is expected once the command has been transmitted.
On that path trf7970a completes the command with

	trf->rx_skb = ERR_PTR(0);

which evaluates to NULL.  IS_ERR(NULL) is false, so the NULL response
passes the !IS_ERR() check and cmd->resp->data and cmd->resp->len are
dereferenced whenever the debug print site is enabled.  The driver
guards its own dump with "trf->rx_skb && !IS_ERR(trf->rx_skb)"; the
digital layer is missing the NULL half of that test.

Use IS_ERR_OR_NULL() so that NULL responses are skipped as well.  The
callback on that path, digital_tg_send_psl_res_complete(), never
dereferences resp and dev_kfree_skb() accepts NULL, so only the debug
dump needs fixing.

Fixes: 59ee2361c9 ("NFC Digital: Implement driver commands mechanism")
Signed-off-by: Linmao Li <lilinmao@kylinos.cn>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://patch.msgid.link/20260710061254.80975-1-lilinmao@kylinos.cn
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:03 +02:00
Yinhao Hu
47792358a6
nfc: pn533: hold a reference to the request skb during send_frame
__pn533_send_async() publishes the command and then calls
dev->phy_ops->send_frame(). Once dev->cmd is set, an incoming frame
can be matched to this command: the I2C threaded IRQ runs
pn533_recv_frame(), which queues cmd_complete_work, and
pn533_send_async_complete() frees cmd->req with consume_skb().

On the I2C transport, pn533_i2c_send_frame() still dereferences the same
skb after i2c_master_send() returns, so a completion that races the
send can free the skb while the transport is still using it.

The request skb is owned by the command object and may be freed by
command completion at any time after dev->cmd is published, so the
transport send path must not assume it stays alive. Hold a temporary
reference to the request skb across the send_frame() call so the
transport always sees a live skb even if completion races the send.
Add a pn533_send_cmd_frame() helper and use it from all three send
paths.

Fixes: 9815c7cf22 ("NFC: pn533: Separate physical layer from the core implementation")
Signed-off-by: Yinhao Hu <dddddd@hust.edu.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260626073434.3977525-1-dddddd@hust.edu.cn
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:03 +02:00
Samuel Page
8cbe06c1e6
nfc: nci: fix uninit-value in the RF discover/activated NTF handlers
nci_rf_discover_ntf_packet() and nci_rf_intf_activated_ntf_packet() each
parse a notification into an on-stack struct (nci_rf_discover_ntf /
nci_rf_intf_activated_ntf) that is not initialised. The RF
technology-specific parameters are only extracted when
rf_tech_specific_params_len is non-zero, so a notification that reports a
zero length leaves the rf_tech_specific_params union uninitialised - and
both handlers then pass it to nci_add_new_protocol(), which reads it:

 - discover:  nci_add_new_target() -> nci_add_new_protocol();
 - activated: nci_target_auto_activated() -> nci_add_new_protocol().

nci_add_new_protocol() uses nfca_poll->nfcid1_len as both a branch
condition and a memcpy() length and copies nfcid1/sens_res/sel_res into
ndev->targets, which is later exposed to user space via NFC_CMD_GET_TARGET.

  BUG: KMSAN: uninit-value in nci_add_new_protocol+0x624/0x6c0
   nci_add_new_protocol+0x624/0x6c0
   nci_ntf_packet+0x25b2/0x3c30
   nci_rx_work+0x318/0x5d0
   process_scheduled_works+0x84b/0x17a0
   worker_thread+0xc10/0x11b0
   kthread+0x376/0x500
  Local variable ntf.i created at:
   nci_ntf_packet+0xbc2/0x3c30

Zero-initialise both on-stack notifications so the union reads back as
zero when no technology-specific parameters are present.

Fixes: 019c4fbaa7 ("NFC: Add NCI multiple targets support")
Fixes: e8c0dacd98 ("NFC: Update names and structs to NCI spec 1.0 d18")
Link: https://lore.kernel.org/netdev/20260623172109.1105965-2-horms@kernel.org/
Cc: stable@vger.kernel.org
Assisted-by: Bynario AI
Signed-off-by: Samuel Page <sam@bynar.io>
Link: https://patch.msgid.link/20260626090301.2139500-1-sam@bynar.io
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:03 +02:00
Bryam Vargas
7ad21dcfeb
nfc: fdp: bound the device-reported read length and fix an skb leak
fdp_nci_i2c_read() takes the next packet length from two device-supplied
bytes and never validates it. The value is a u16 used as the
i2c_master_recv() count into a 261-byte on-stack buffer: a malicious,
counterfeit or malfunctioning controller (or an i2c bus interposer) can
drive it far past the buffer for a stack out-of-bounds write that
clobbers the canary and return address, or below the minimum frame size
(directly, or by truncating the computed sum) so the header/LRC strip
and the next length read run past a short receive. Reject a length
outside [FDP_NCI_I2C_MIN_PAYLOAD, FDP_NCI_I2C_MAX_PAYLOAD], as a
corrupted packet already is, and force resynchronization.

The same loop allocates one data skb per iteration and assumes a length
packet followed by a data packet; a device that sends two data packets
in one call leaks the first skb when the second allocation overwrites
it. Free a previously allocated skb before allocating the next.

Fixes: a06347c04c ("NFC: Add Intel Fields Peak NFC solution driver")
Cc: stable@vger.kernel.org
Suggested-by: Simon Horman <horms@kernel.org>
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Link: https://patch.msgid.link/20260616-b4-disp-b1f8ab4c-v2-1-2d1fe5955325@proton.me
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:02 +02:00
Samuel Page
ac200079db
nfc: nci: fix out-of-bounds write in nci_target_auto_activated()
nci_target_auto_activated() appends a target to the fixed-size array
ndev->targets[NCI_MAX_DISCOVERED_TARGETS] and increments ndev->n_targets
without first checking the array is full; unlike its sibling
nci_add_new_target(), which bails out when n_targets already equals
NCI_MAX_DISCOVERED_TARGETS.

ndev->n_targets is only cleared by nci_clear_target_list(), so an NFCC
that repeatedly re-runs discovery (RF_DISCOVER_RSP, which re-enters
NCI_DISCOVERY without clearing the target list) and reports an
auto-activated target (RF_INTF_ACTIVATED_NTF) drives n_targets past the
limit. The append then writes a struct nfc_target past the end of the
array (a slab out-of-bounds write), and nfc_targets_found() goes on to
walk the array with the inflated count:

  BUG: KASAN: slab-out-of-bounds in nci_add_new_protocol+0x94/0x2ac [nci]
  Write of size 2 at addr ffff0000c7299a18 by task kworker/u8:0/12
  Workqueue: nfc0_nci_rx_wq nci_rx_work [nci]
  Call trace:
   nci_add_new_protocol+0x94/0x2ac [nci]
   nci_ntf_packet+0xddc/0x11a0 [nci]
   nci_rx_work+0x15c/0x1e0 [nci]
   process_one_work+0x2dc/0x500
   worker_thread+0x240/0x460
   kthread+0x1c0/0x1d0
   ret_from_fork+0x10/0x20

  The buggy address belongs to the cache kmalloc-2k of size 2048
  The buggy address is located 1024 bytes to the right of
  allocated 1560-byte region [ffff0000c7299000, ffff0000c7299618)

Guard nci_target_auto_activated() with the same check used by
nci_add_new_target().

Fixes: 019c4fbaa7 ("NFC: Add NCI multiple targets support")
Cc: stable@vger.kernel.org
Assisted-by: Bynario AI
Signed-off-by: Samuel Page <sam@bynar.io>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260622145243.3167276-1-sam@bynar.io
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:02 +02:00
Bryam Vargas
0428fa2c22
nfc: nci: add data_len bound checks to activation parameter extractors
nci_extract_activation_params_iso_dep() and
nci_extract_activation_params_nfc_dep() read an inner length byte from
the NCI RF_INTF_ACTIVATED_NTF payload and use it to memcpy() into fixed
kernel buffers, but neither function receives the caller-validated
activation_params_len.  A crafted NCI notification with
activation_params_len=1 and an inner length byte of up to 20 (NFC-A) or
50 (NFC-B) causes memcpy() to read that many bytes past the one valid
byte in the activation params region -- a slab out-of-bounds read of
kernel memory adjacent to the NCI skb.

The sibling nci_extract_rf_params_*() family was given equivalent
protection by commit 571dcbeb8e ("net: nfc: nci: Fix parameter
validation for packet data"), but the two activation parameter
extractors were not updated at that time.

Add a data_len parameter to both functions, guard against an empty
region before consuming the inner length byte, decrement the remaining
count after consuming it, and clamp the copy length to what is actually
available.  Update both call sites to pass ntf.activation_params_len,
which is already validated against the skb at ntf.c:801.

Fixes: e8c0dacd98 ("NFC: Update names and structs to NCI spec 1.0 d18")
Cc: stable@vger.kernel.org
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Link: https://patch.msgid.link/20260612-b4-disp-6d52d8b0-v3-1-e26221f8826d@proton.me
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:02 +02:00
Muhammad Bilal
78b20c8eea
nfc: llcp: fix OOB read and u8 offset wrap in TLV parsers
nfc_llcp_parse_gb_tlv() and nfc_llcp_parse_connection_tlv() contain
three related bugs in their TLV parsing loops:

1. 'offset' is declared u8 but tlv_array_len is u16. When TLV data
   advances offset past 255 it silently wraps to zero, causing
   infinite loops or double-processing of buffer data.

2. Before reading tlv[0] (type) and tlv[1] (length) there is no
   check that offset+2 <= tlv_array_len. A truncated TLV causes
   an OOB read of one byte past the buffer end.

3. After reading the length field, the value bytes are accessed
   without checking offset+2+length <= tlv_array_len. A crafted
   length=0xFF on a short buffer causes up to 255 bytes of OOB
   read past the buffer end.

Both functions are reachable without authentication via
nfc_llcp_set_remote_gb() which feeds remote LLCP general bytes
directly into nfc_llcp_parse_gb_tlv() with no additional
validation.

Fix all three issues by widening offset from u8 to u16 and adding
bounds checks for both the TLV header and value field before each
access.

Fixes: 3df40eb3a2 ("nfc: constify several pointers to u8, char and sk_buff")
Cc: stable@vger.kernel.org
Signed-off-by: Muhammad Bilal <meatuni001@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260622131802.239035-1-meatuni001@gmail.com
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:02 +02:00
Doruk Tan Ozturk
f4c7f37f0a
nfc: llcp: bound SNL TLV parsing to the skb and add length checks
nfc_llcp_recv_snl() walked the SNL TLV list using a u16 offset/length
pair derived from skb->len, without bounding reads to the actual skb
data. Three problems followed:

  - For a short frame (skb->len < LLCP_HEADER_SIZE), tlv_len underflowed.
  - The per-TLV header (type, length) was read without checking that two
    bytes remained.
  - A declared TLV length could run past the end of the buffer, and an
    SDREQ with length == 0 made "service_name_len = length - 1" underflow
    (size_t), driving an out-of-bounds read in the following strncmp() /
    nfc_llcp_sock_from_sn(). The SDRES case likewise read tlv[2]/tlv[3]
    without a length check.

A nearby NFC device can reach this without authentication; LLCP link
activation happens automatically after NFC-DEP.

Walk the TLV list by pointer, bounded by skb_tail_pointer() over the
linear skb data, and validate each TLV declared length before use. Add
explicit length checks for SDREQ (>= 1) and SDRES (exactly 2).

Found by 0sec automated security-research tooling (https://0sec.ai).

Fixes: 19cfe5843e ("NFC: Initial SNL support")
Signed-off-by: Doruk Tan Ozturk <doruk@0sec.ai>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260609202543.42282-1-doruk@0sec.ai
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:02 +02:00
Doruk Tan Ozturk
344a56d7c8
nfc: digital: clamp SENSF_RES length to the destination buffer
digital_in_recv_sensf_res() memcpy()s resp->len bytes from a remote
NFC-F device response into the NFC_SENSF_RES_MAXSIZE-byte target.sensf_res
field without an upper-bound check. A nearby malicious NFC-F device can
send an oversized SENSF_RES response to overflow the stack-local struct
nfc_target.

Clamp resp->len to NFC_SENSF_RES_MAXSIZE before the copy.

Found by 0sec automated security-research tooling (https://0sec.ai).

Fixes: 8c0695e499 ("NFC Digital: Add NFC-F technology support")
Cc: stable@vger.kernel.org
Signed-off-by: Doruk Tan Ozturk <doruk@0sec.ai>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://patch.msgid.link/20260603141355.68156-1-doruk@0sec.ai
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:02 +02:00
Zhenghang Xiao
8265a626cc
nfc: nci: fix double completion race in nci_data_exchange_complete
nci_close_device() and nci_rx_work can both call
nci_data_exchange_complete() concurrently.  After commit 4527025d44
("nfc: nci: fix circular locking dependency in nci_close_device") moved
flush_workqueue(ndev->rx_wq) after mutex_unlock(&ndev->req_lock),
rx_work is no longer serialized with the explicit completion call in the
close path.  Both callers read the non-NULL callback pointer and invoke
rawsock_data_exchange_complete(), which calls sock_put() -- but only one
sock_hold() was taken, so the second sock_put() underflows the refcount
and frees the socket while it is still in use.

Replace the bare clear_bit(NCI_DATA_EXCHANGE) with
test_and_clear_bit() so that only the first caller proceeds to invoke
the callback.

Fixes: 4527025d44 ("nfc: nci: fix circular locking dependency in nci_close_device")
Signed-off-by: Zhenghang Xiao <kipreyyy@gmail.com>
Link: https://patch.msgid.link/20260526103121.47957-1-kipreyyy@gmail.com
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:02 +02:00
Breno Leitao
3681252705
nfc: llcp: read llcp_sock->local under the socket lock in getsockopt
nfc_llcp_getsockopt() read llcp_sock->local before lock_sock(sk) and
then dereferenced the cached pointer inside the locked region.
llcp_sock_bind() assigns and clears llcp_sock->local under the same
socket lock, dropping the last reference on its error path. A
getsockopt() racing an in-flight bind() can observe the pointer, block
on lock_sock(), and then dereference a freed nfc_llcp_local once bind()
has unwound.

Move the llcp_sock->local read and the NULL check inside the
lock_sock(sk) region so bind() cannot mutate or free the pointer between
the load and the use.

Fixes: 26fd76cab2 ("NFC: llcp: Implement socket options")
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260521-fix_llc-v2-2-ab44cc09179c@debian.org
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:02 +02:00
Breno Leitao
99985bfa83
nfc: llcp: avoid userspace overflow on invalid optlen
nfc_llcp_getsockopt() casts optval to (u32 __user *) for put_user(), so
the kernel always stores 4 bytes regardless of the caller-supplied
optlen. The existing min_t(u32, len, sizeof(u32)) only clamps the length
reported back to userspace; it does not constrain the store. A call with
optlen < 4 therefore writes past the user buffer, violating the
getsockopt(2) contract for all five supported optnames.

Reject any call with optlen < sizeof(u32) up front. 'len' is int, so a
plain size comparison would promote a negative optlen to size_t and slip
past the check; an explicit 'len < 0' test is added first to catch
negative values before the size compare.

Fixes: 26fd76cab2 ("NFC: llcp: Implement socket options")
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260521-fix_llc-v2-1-ab44cc09179c@debian.org
Signed-off-by: David Heidelberg <david@ixit.cz>
2026-08-11 18:10:01 +02:00
Linus Torvalds
db2ddb8714 Linux 7.2-rc7 2026-08-09 14:54:50 -07:00
Linus Torvalds
b9b3e33b70 tracing fixes for 7.2:
- Fix use-after-free in eventfs_remove_rec()
 
   The freeing of the eventfs_inode children used list_for_each_entry() where
   the child is freed via srcu, but there's still a chance that it gets freed.
   It should be using list_for_each_entry_safe().
 
 - Fix eventfs_inode SRCU use of list in freeing
 
   The iterator uses an SRCU protected list walk on the eventfs inodes. The
   eventfs inode uses its "list" field in a union with the RCU list head.
   When the inode gets added to the SRCU list it immediately corrupts the
   list pointer and can cause an issue with the iterator. Move the RCU list
   head to be shared with the children list head which allows the iterator to
   check the parent inode if is freed before referencing the child. Have the
   iterator check the parent "is_freed" field and break out if it is set.
   Also add memory barriers to make sure the ordering is correct.
 
 - Fix various RCU synchronization issues with direct_functions
 
   Updates to direct_functions have some missing RCU protection and
   synchronization. Restructure the code a bit to make sure updates to the
   direct_functions are protected.
 
 - Remove an unneeded comma from a scope_guard()
 
   There's a spurious comma in a scope_guard(). Remove it.
 
 - Fix race in per CPU buffer swap in the ring buffer
 
   When a per CPU buffer swap happens, it must make sure that it doesn't
   occur while a writer is active. Instead it returns an -EBUSY. But there's
   a small race window when a writer moves from one sub-buffer to the next
   that it resets the "committing" counter. If a swap happens at that moment,
   the buffer used for the commit of an event will not match the buffer the
   event is actually on. Instead of using the "committing" counter, use the
   recursive detection counter that does not get reset when the writer
   crosses sub-buffers.
 
 - Fix off-by-one in ftrace_free_mem()
 
   The function ftrace_free_mem() gets an "end_ptr" as a parameter that is
   exclusive to the rang to be freed. But its value is used to search for the
   records that expects an inclusive value. Subtract one from the parameter
   to convert it to an inclusive range.
 
 - Disable resizing of the ring buffer for persistent buffers
 
   Resizing the persistent buffer has undefined behavior. Prevent it from
   being resized.
 
 - Disable changing ring buffer subbuf order when resizing is disabled
 
   The ring buffer subbuffer order can not be changed during resizing. Use
   that instead of just checking if the buffer is mapped as mapped buffers
   also have resizing disabled.
 
 - Initialize subbuf_order of reader pages when they are created
 
   In rb_allocate_cpu_buffer() the bpage->order is not updated to the current
   subbuf_order leaving it as zero. This value is used when the page is freed.
 
 - Fix test_ringbuffer() to test for ERR_PTR before calling kthread_stop()
 
   The rb_threads[] array is assigned the output of kthread_run_on_cpu()
   which could return an ERR_PTR. At the end of the test, all threads in the
   array are cleaned up by kthread_stop() passing in the value in the array
   if it isn't zero. But if the array contains an ERR_PTR, kthread_stop()
   will not be able to handle it properly.
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Merge tag 'trace-v7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix use-after-free in eventfs_remove_rec()

   The freeing of the eventfs_inode children used list_for_each_entry()
   where the child is freed via srcu, but there's still a chance that it
   gets freed. It should be using list_for_each_entry_safe().

 - Fix eventfs_inode SRCU use of list in freeing

   The iterator uses an SRCU protected list walk on the eventfs inodes.
   The eventfs inode uses its "list" field in a union with the RCU list
   head. When the inode gets added to the SRCU list it immediately
   corrupts the list pointer and can cause an issue with the iterator.
   Move the RCU list head to be shared with the children list head which
   allows the iterator to check the parent inode if is freed before
   referencing the child. Have the iterator check the parent "is_freed"
   field and break out if it is set. Also add memory barriers to make
   sure the ordering is correct.

 - Fix various RCU synchronization issues with direct_functions

   Updates to direct_functions have some missing RCU protection and
   synchronization. Restructure the code a bit to make sure updates to
   the direct_functions are protected.

 - Remove an unneeded comma from a scope_guard()

   There's a spurious comma in a scope_guard(). Remove it.

 - Fix race in per CPU buffer swap in the ring buffer

   When a per CPU buffer swap happens, it must make sure that it doesn't
   occur while a writer is active. Instead it returns an -EBUSY. But
   there's a small race window when a writer moves from one sub-buffer
   to the next that it resets the "committing" counter. If a swap
   happens at that moment, the buffer used for the commit of an event
   will not match the buffer the event is actually on. Instead of using
   the "committing" counter, use the recursive detection counter that
   does not get reset when the writer crosses sub-buffers.

 - Fix off-by-one in ftrace_free_mem()

   The function ftrace_free_mem() gets an "end_ptr" as a parameter that
   is exclusive to the rang to be freed. But its value is used to search
   for the records that expects an inclusive value. Subtract one from
   the parameter to convert it to an inclusive range.

 - Disable resizing of the ring buffer for persistent buffers

   Resizing the persistent buffer has undefined behavior. Prevent it
   from being resized.

 - Disable changing ring buffer subbuf order when resizing is disabled

   The ring buffer subbuffer order can not be changed during resizing.
   Use that instead of just checking if the buffer is mapped as mapped
   buffers also have resizing disabled.

 - Initialize subbuf_order of reader pages when they are created

   In rb_allocate_cpu_buffer() the bpage->order is not updated to the
   current subbuf_order leaving it as zero. This value is used when the
   page is freed.

 - Fix test_ringbuffer() to test for ERR_PTR before calling
   kthread_stop()

   The rb_threads[] array is assigned the output of kthread_run_on_cpu()
   which could return an ERR_PTR. At the end of the test, all threads in
   the array are cleaned up by kthread_stop() passing in the value in
   the array if it isn't zero. But if the array contains an ERR_PTR,
   kthread_stop() will not be able to handle it properly.

* tag 'trace-v7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Fix crash passing ERR_PTR to kthread_stop()
  ring-buffer: Initialise reader page order in rb_allocate_cpu_buffer()
  ring-buffer: Prevent subbuf order change when resizing is disabled
  ring-buffer: Prevent resizing of persistent ring buffer
  ftrace: Fix off-by-one fentry site disable in ftrace_free_mem()
  ring-buffer: Use current_context for safe per-CPU buffer swap
  ftrace: Drop extra comma in trace_buffered_event_enable
  ftrace: Protect direct_functions in update_ftrace_direct_mod
  ftrace: Protect direct_functions in update_ftrace_direct_del
  ftrace: Protect direct_functions in ftrace_find_rec_direct
  eventfs: Use children field for rcu head and add memory barriers
  eventfs: Fix use-after-free in eventfs_remove_rec()
2026-08-09 08:47:31 -07:00
Linus Torvalds
b643e495ae s390 updates for 7.2-rc7
- Fix potential uninitialized memory reads and buffer overflows from
   malformed zcrypt CCA and EP11 requests by properly validating lengths
   and payloads
 
 - Fix possible out of bounds accesses in zcrypt EP11 domain handling by
   replacing fixed payload layout assumptions with parsing ASN.1 fields
   with bounds checks
 
 - Fix zcrypt CCA and EP11 request and reply buffer allocations missing
   required 4-byte padding, and scrub the full allocation on release
 
 - Fix zcrypt CCA and EP11 messages leaking up to 3 uninitialized bytes
   of memory by zeroing trailing alignment padding
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Merge tag 's390-7.2-7' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 fixes from Vasily Gorbik:

 - Fix potential uninitialized memory reads and buffer overflows from
   malformed zcrypt CCA and EP11 requests by properly validating lengths
   and payloads

 - Fix possible out of bounds accesses in zcrypt EP11 domain handling by
   replacing fixed payload layout assumptions with parsing ASN.1 fields
   with bounds checks

 - Fix zcrypt CCA and EP11 request and reply buffer allocations missing
   required 4-byte padding, and scrub the full allocation on release

 - Fix zcrypt CCA and EP11 messages leaking up to 3 uninitialized bytes
   of memory by zeroing trailing alignment padding

* tag 's390-7.2-7' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/zcrypt: Pad trailing CCA or EP11 message with zeros
  s390/zcrypt: Improve EP11 CPRB domain handling with ASN.1 parsing
  s390/zcrypt: Improve EP11 CPRB length and overflow checks
  s390/zcrypt: Improve CCA CPRB length and overflow checks
  s390/zcrypt: Fix CPRB memory allocation in zcrypt misc code
2026-08-09 06:31:16 -07:00
Hui Su
91542863ab ring-buffer: Fix crash passing ERR_PTR to kthread_stop()
In test_ringbuffer()'s out_free cleanup loop, the check
`!rb_threads[cpu]` only catches NULL entries and misses entries that
hold an ERR_PTR.

rb_threads[] is static, so unassigned slots are NULL. But when
kthread_run_on_cpu() fails for a cpu, it stores ERR_PTR(-ENOMEM) (or
-EINTR) in rb_threads[cpu] before the creation loop jumps to out_free.
That entry is non-NULL, so the old `!ptr` check does not break, and the
cleanup proceeds to call kthread_stop() on the ERR_PTR. kthread_stop()
then dereferences the bogus pointer, crashing the kernel during the
late_initcall self-test.

crash logs:
  BUG: kernel NULL pointer dereference, address: 000000000000001c
  Oops: 0002 [#1] SMP NOPTI
  CPU: 1 PID: 1 Comm: swapper/0 Not tainted 7.2.0-rc6-dirty #7 PREEMPT(lazy)
  RIP: 0010:kthread_stop+0x2e/0x220
  RBX: fffffffffffffff4
  CR2: 000000000000001c
  Call Trace:
   <TASK>
   test_ringbuffer+0x1ec/0x650
   do_one_initcall+0x6c/0x2c0
   kernel_init_freeable+0x21d/0x420
   kernel_init+0x15/0x1c0
   ret_from_fork+0x21b/0x320
   </TASK>
  Kernel panic - not syncing: Fatal exception

Cc: stable@vger.kernel.org
Fixes: 64ed3a049e ("ring-buffer: make use of the helper function kthread_run_on_cpu()")
Link: https://patch.msgid.link/20260807154145.2846521-2-sh_def@163.com
Signed-off-by: Hui Su <sh_def@163.com>
Reviewed-by: Vincent Donnefort <vdonnefort@google.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:26:30 -04:00
Vincent Donnefort
6d014e44b6 ring-buffer: Initialise reader page order in rb_allocate_cpu_buffer()
In rb_allocate_cpu_buffer(), bpage->order was omitted, leaving it as 0.
This is an issue for a ring-buffer with subbufs bigger than PAGE_SIZE if
when freed: free_buffer_page() relies on this value. Align the value
with the actual allocation size (buffer::subbuf_order).

Cc: stable@vger.kernel.org
Fixes: f9b94daa54 ("ring-buffer: Set new size of the ring buffer sub page")
Link: https://patch.msgid.link/20260806211306.3704194-4-vdonnefort@google.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:26:11 -04:00
Vincent Donnefort
bf98d7b0d5 ring-buffer: Prevent subbuf order change when resizing is disabled
Because ring_buffer_subbuf_order_set() frees buffer pages, we can't
allow it when resizing is disabled. A non-consuming reader is at risk of
use-after-free (rb_advance_iter()).

Return -EBUSY on resize_disabled, matching ring_buffer_resize()
behaviour.

Cc: stable@vger.kernel.org
Fixes: f9b94daa54 ("ring-buffer: Set new size of the ring buffer sub page")
Link: https://patch.msgid.link/20260806211306.3704194-3-vdonnefort@google.com
Reported-by: syzbot+e0cc44465d6bae735679@syzkaller.appspotmail.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:23:45 -04:00
Vincent Donnefort
7c727dfce6 ring-buffer: Prevent resizing of persistent ring buffer
Dynamically resizing a persistent ring buffer is not possible. Disable
the feature.

Cc: stable@vger.kernel.org
Fixes: be68d63a13 ("ring-buffer: Add ring_buffer_alloc_range()")
Link: https://patch.msgid.link/20260806211306.3704194-2-vdonnefort@google.com
Signed-off-by: Vincent Donnefort <vdonnefort@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:23:18 -04:00
Josh Poimboeuf
8b8292d648 ftrace: Fix off-by-one fentry site disable in ftrace_free_mem()
When a module's init text is freed, do_init_module() calls
ftrace_free_mem() with a half-open [start, end) range.  However the
ftrace_cmp_recs() comparator treats the upper bound as inclusive, as all
its other users do, passing 'ip + size - 1'.  So ftrace_free_mem() can
delete a record sitting exactly at 'end', which is outside the freed
range.

For a kernel without CFI or IBT, the first record of a function is at
the function start, which for the first function in a module is also the
base of its text allocation.  As the module allocator packs its regions,
that address is often the 'end' passed by a neighboring module's
do_init_module(), causing the first function's ftrace location to get
disabled, preventing an attempt to livepatch it:

  livepatch: failed to find location for function 'pcspkr_probe'

Convert the exclusive end to the inclusive 'end - 1' the comparator
expects, and return early for an empty range to avoid the subtraction
from underflowing when the init text size is zero.

Cc: stable@vger.kernel.org
Fixes: 42c269c88d ("ftrace: Allow for function tracing to record init functions on boot up")
Link: https://patch.msgid.link/1b5ccfa8095bdb1277f84af1c2c2e2205aca03ae.1785992188.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:22:41 -04:00
Tengda Wu
f27bdc4307 ring-buffer: Use current_context for safe per-CPU buffer swap
The ring_buffer_swap_cpu() function currently checks the per-CPU
committing counter to determine if a buffer is actively being written to
before performing the swap. However, there exists a race window where
this check can be bypassed:

    ring_buffer_lock_reserve
        cpu_buffer = buffer->buffers[cpu];       // cpu_buffer_a
        rb_reserve_next_event
            rb_start_commit // inc committing
            if (unlikely(READ_ONCE(cpu_buffer->buffer) != buffer)) {...}
            __rb_reserve_next
                rb_move_tail
                    rb_end_commit(cpu_buffer);   // dec committing => 0
                    /* interrupt hits here, successfully swaps! */
                    local_inc(&cpu_buffer->committing);

    ring_buffer_unlock_commit
        cpu_buffer = buffer->buffers[cpu];      // cpu_buffer_b
        rb_commit
            rb_end_commit
            RB_WARN_ON(cpu_buffer, !local_read(&cpu_buffer->committing))
                                                // triggers warning

The committing counter can temporarily drop to 0 during a single write
operation (within rb_move_tail), creating a window where swap can
succeed even though the write is still in progress. This leads to
inconsistent buffer state and triggers the RB_WARN_ON in rb_commit().

Replace the committing counter check with current_context checks, which
are set at the entry of ring_buffer_lock_reserve() and remain valid
throughout the entire write operation, providing a reliable indicator of
buffer busy state during swap.

Cc: stable@vger.kernel.org
Fixes: 4239c38fe0 ("ring-buffer: Process commits whenever moving to a new page.")
Link: https://patch.msgid.link/20260803005640.2445666-2-wutengda@huaweicloud.com
Signed-off-by: Tengda Wu <wutengda@huaweicloud.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 22:22:06 -04:00
Linus Torvalds
06cf61899d - Fix MCE CMCI discovery initialization ordering bug
(Breno Leitao)
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'x86-urgent-2026-08-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fix from Ingo Molnar:

 - Fix MCE CMCI discovery initialization ordering bug (Breno Leitao)

* tag 'x86-urgent-2026-08-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Set up the polling timer before CMCI discovery
2026-08-08 16:43:07 -07:00
Linus Torvalds
d4eee3bdb8 - Fix race in futex_pivot_pending() during private hash resize
that can cause stuck tasks (Yao Kai)
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'locking-urgent-2026-08-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull futex fix from Ingo Molnar:

 - Fix race in futex_pivot_pending() during private hash resize
   that can cause stuck tasks (Yao Kai)

* tag 'locking-urgent-2026-08-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  futex: Fix race in futex_pivot_pending() during private hash resize
2026-08-08 16:39:53 -07:00
Linus Torvalds
91a73db697 USB / Thunderbolt fixes for 7.2-rc7
Here are some small USB and Thunderbolt driver fixes for 7.2-rc7 that
 resolve some reported issues.  Included in here are:
   - new quirk for some broken USB devices
   - thunderbolt device fixes for reported issues
   - usb gadget driver fix
   - usb atm driver fix
   - xhci driver fixes.
   - other minor USB driver fixes
 
 All of these have been in linux-next this week with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB / Thunderbolt fixes from Greg KH:
 "Here are some small USB and Thunderbolt driver fixes for 7.2-rc7 that
  resolve some reported issues. Included in here are:

   - new quirk for some broken USB devices

   - thunderbolt device fixes for reported issues

   - usb gadget driver fix

   - usb atm driver fix

   - xhci driver fixes.

   - other minor USB driver fixes

  All of these have been in linux-next this week with no reported
  issues"

* tag 'usb-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: xhci: use BIT_ULL for CRCR bits to fix incorrect 64bit mask
  usb: quirks: Add ShanWan gamepad to quirk list
  usb: hub: Split announce_device() to log device identity before enumeration
  usb: core: Add quirk for 255-bytes initial config read
  usb: atm: cxacru: properly kill rcv_urb on error in cxacru_cm()
  usb: misc: usbio: check ibuf_len against rxbuf_len in bulk msg
  usb: gadget: f_ncm: Use unsigned int for ndp_index
  usb: cdnsp: fix incorrect endian conversions for APB timeout register
  thunderbolt: Initialize ->domain_released completion before it is being used
  thunderbolt: icm: Preserve USB4 proxy data-valid bit
  thunderbolt: Bound the DROM dual link port number before indexing sw->ports
  thunderbolt: Fix bandwidth group reservation indexing
  thunderbolt: stream: Unmap buffers with mapped size
2026-08-08 16:33:04 -07:00
Linus Torvalds
e4836b67ba TTY / Serial / VT driver fixes for 7.2-rc7
Here are some small serial and vt tty driver fixes for 7.2-rc7 that
 resolve some reported problems.  Included in here are:
   - 2 vt core fixes
   - amba-pl011 serial driver fixes
   - 8250_of and 8250_dma driver fixes
   - qcom-geni serial driver fix
   - sc16is7xx serial driver fix
 
 All of these have been in linux-next this week with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial / vt driver fixes from Greg KH:
 "Here are some small serial and vt tty driver fixes for 7.2-rc7 that
  resolve some reported problems. Included in here are:

   - two vt core fixes

   - amba-pl011 serial driver fixes

   - 8250_of and 8250_dma driver fixes

   - qcom-geni serial driver fix

   - sc16is7xx serial driver fix

  All of these have been in linux-next this week with no reported
  issues"

* tag 'tty-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: amba-pl011: synchronize DMA teardown
  serial: amba-pl011: cancel RS485 hrtimers after freeing IRQ
  serial: amba-pl011: fix indefinite RS485 post-send delay
  vt: add permission check for KDSKBMETA ioctl
  vt: stabilize tty reference in kbd_keycode with tty_port_tty_get
  serial: 8250_of: clear stuck empty-FIFO RX-timeout on LPC32xx
  serial: qcom-geni: fix TX DMA buffer flush
  serial: 8250_dma: Clear stale RX state on shutdown
  serial: sc16is7xx: enable THRI before filling TX FIFO
2026-08-08 16:31:15 -07:00
Linus Torvalds
e663f6deac Staging driver fixes for 7.2-rc7
Here are some more small staging driver fixes, just for the rtl8723bs
 driver, for some reported problems found with it now that people are
 starting to actually test the thing with "bad" networks.
 
 Nothing major, but good to have in the -final release.  All of these
 have been in linux-next for over a week with no reported problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging driver fixes from Greg KH:
 "Here are some more small staging driver fixes, just for the rtl8723bs
  driver, for some reported problems found with it now that people are
  starting to actually test the thing with "bad" networks.

  Nothing major, but good to have in the -final release. All of these
  have been in linux-next for over a week with no reported problems"

* tag 'staging-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: rtl8723bs: validate monitor transmit frame lengths
  staging: rtl8723bs: fix missing shared-key auth challenge length check
  staging: rtl8723bs: fix OOB read in WMM_param_handler()
  staging: rtl8723bs: fix OOB read in rtw_get_wpa_ie()
2026-08-08 16:29:33 -07:00
Linus Torvalds
5668ba2304 Char / Misc and documentation fixes for 7.2-rc7
Here are some small char/misc and nvmem and documentation fixes for
 7.2-rc7 to resolve some reported issues.  Included in here are:
   - updates to the documentation for the kernel threat model and
     security bugs to get the LLMs to actually follow what we have been
     asking them to do (i.e. not claim security issues for things we do
     not consider security issues.)
   - nvmem driver fixes which required a tiny "layout" driver to be
     added.
   - fastrpc driver fixes
   - mei driver fix
   - counter driver fix
   - binder driver fix
 
 All of these have been in linux-next this week with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char / misc and documentation fixes from Greg KH:
 "Here are some small char/misc and nvmem and documentation fixes for
  7.2-rc7 to resolve some reported issues.  Included in here are:

   - updates to the documentation for the kernel threat model and
     security bugs to get the LLMs to actually follow what we have been
     asking them to do (i.e. not claim security issues for things we do
     not consider security issues.)

   - nvmem driver fixes which required a tiny "layout" driver to be
     added.

   - fastrpc driver fixes

   - mei driver fix

   - counter driver fix

   - binder driver fix

  All of these have been in linux-next this week with no reported
  problems"

* tag 'char-misc-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  docs: security-bugs: clarify some mandatory steps for AI reports
  docs: coding-assistant: explain important steps when looking for bugs
  docs: security-bugs: clarify what counts as a valid version
  docs: threat-model: move fake devices out of "non production use"
  docs: threat-model: clarify "security bug" vs "vulnerability"
  counter: microchip-tcb-capture: Fix DT channel validation
  mei: pull kvfree out of spinlock
  rust_binder: do not query current thread for all ioctls
  nvmem: layouts: Add fixed-layout driver
  nvmem: apple-spmi-nvmem: wrap regmap calls to satisfy CFI
  misc: fastrpc: fix memory leak in fastrpc_channel_ctx_free
  misc: fastrpc: fix channel ctx ref leak when session alloc fails
  misc: fastrpc: take fl->lock when moving mmaps on interrupted invoke
  misc: fastrpc: Remove buffer from list prior to unmap operation
  misc: fastrpc: Fix initial memory allocation for Audio PD memory pool
2026-08-08 16:25:59 -07:00
Leon Hwang
48f2fd0d93 ftrace: Drop extra comma in trace_buffered_event_enable
Drop the extra comma in "scoped_guard()" to cleanup the code.

Link: https://patch.msgid.link/20260730150411.88667-5-leon.hwang@linux.dev
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 11:21:32 -04:00
Leon Hwang
092f8ec7db ftrace: Protect direct_functions in update_ftrace_direct_mod
Fix accessing the __rcu pointer direct_functions with RCU protection.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260730150411.88667-4-leon.hwang@linux.dev
Fixes: e93672f770 ("ftrace: Add update_ftrace_direct_mod function")
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 11:21:27 -04:00
Leon Hwang
f26e5fa75f ftrace: Protect direct_functions in update_ftrace_direct_del
Fix accessing the __rcu pointer direct_functions with RCU protection.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260730150411.88667-3-leon.hwang@linux.dev
Fixes: 8d2c1233f3 ("ftrace: Add update_ftrace_direct_del function")
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 11:21:23 -04:00
Leon Hwang
63444b7617 ftrace: Protect direct_functions in ftrace_find_rec_direct
Fix accessing the __rcu pointer direct_functions with RCU protection.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260730150411.88667-2-leon.hwang@linux.dev
Fixes: d05cb47066 ("ftrace: Fix modification of direct_function hash while in use")
Acked-by: Jiri Olsa <jolsa@kernel.org>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Leon Hwang <leon.hwang@linux.dev>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 11:21:04 -04:00
Linus Torvalds
a7c7074b58 fbdev core fixes for 7.2-rc7:
A few patches for the core fbdev layer which stabilize or fix potential
 issues with text font rendering after screen rotation or after user
 initiated font changes and locking fixes for sysfb during modifications
 of the graphics mode database.
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Merge tag 'fbdev-for-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev

Pull fbdev fixes from Helge Deller:
 "A few patches for the core fbdev layer which stabilize or fix
  potential issues with text font rendering after screen rotation or
  after user initiated font changes and locking fixes for sysfb during
  modifications of the graphics mode database"

* tag 'fbdev-for-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/linux-fbdev:
  fbdev: bitblit: bound-check glyph index in bit_cursor()
  fbdev: Fix out-of-bounds access when rotating console after font resize
  fbdev: core: Fix pointer desynchronization in fb_io_read()
  fbdev: serialize mode sysfs access with lock_fb_info()
  fbdev: clear fb_info->mode before deleting a videomode
  fbdev: bound mode sysfs output to the sysfs buffer
2026-08-08 07:47:52 -07:00
Steven Rostedt
f0ece16ffc eventfs: Use children field for rcu head and add memory barriers
When an eventfs inode is freed, it sets ei->is_freed and then uses its
ei->list to add it to the srcu link list as the list field is a union with
the rcu list head. As the ei->list is used to iterate over an SRCU
protected list without taking the eventfs_mutex, there's nothing stopping
the iteration over that list to see the ei->rcu instead of the ei->list
and it will read a corrupt target.

To fix this, change the union of the rcu list head with the children list.
On freeing the eventfs inode, set the is_free and execute a smp_wmb()
before adding the eventfs inode to the SRCU list.

On iteration of the ei->children list, at the start, execute a smp_rmb()
and then read the is_freed of the ei to see if the children list is still
valid. If is_freed is set, then the ei_child read is not valid and the
loop should exit immediately.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260808094215.4252430d@robin
Fixes: 704f960dbe ("eventfs: Read ei->entries before ei->children in eventfs_iterate()")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260806022719.375354-1-shuangpeng.kernel%40gmail.com
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 10:36:05 -04:00
Shuangpeng Bai
fd73b69170 eventfs: Fix use-after-free in eventfs_remove_rec()
eventfs_remove_rec() recursively removes the child at the current loop
position. After the recursive call returns, list_for_each_entry() advances
by reading list.next from the removed child.

If free_ei() drops the final reference, release_ei() reuses the list/rcu
union to queue an SRCU callback. The child may be freed before that read.
The eventfs_mutex serializes list updates, but it does not keep the removed
child alive or prevent the SRCU callback from running.

Use list_for_each_entry_safe() to save the next sibling before recursively
removing the current child.

Cc: stable@vger.kernel.org
Fixes: 43aa6f97c2 ("eventfs: Get rid of dentry pointers without refcounts")
Link: https://patch.msgid.link/20260806022719.375354-1-shuangpeng.kernel@gmail.com
Signed-off-by: Shuangpeng Bai <shuangpeng.kernel@gmail.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2026-08-08 10:35:33 -04:00
Linus Torvalds
361efac9e9 Driver core fixes for 7.2-rc7
- Fix Rust build failure on s390 by gating ioremap() / iounmap() helpers
   and the io::mem module on CONFIG_HAS_IOMEM; gate affected doctests as
   well.
 
 - Add missing kernel-doc for show_const / store_const union members in
   struct device_attribute.
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Merge tag 'driver-core-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core

Pull driver core fixes from Danilo Krummrich:

 - Fix Rust build failure on s390 by gating ioremap() / iounmap()
   helpers and the io::mem module on CONFIG_HAS_IOMEM; gate affected
   doctests as well.

 - Add missing kernel-doc for show_const / store_const union members in
   struct device_attribute.

* tag 'driver-core-7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
  rust: io: gate ioremap doctests on CONFIG_HAS_IOMEM
  rust: io: gate ioremap/iounmap on CONFIG_HAS_IOMEM
  driver core: add missing kernel-doc for union members
2026-08-08 07:13:29 -07:00
Linus Torvalds
7d8c681eef Input updates for v7.2-rc6
- Fixes for information leaks and OOB accesses across several drivers,
   including evdev, focaltech, edt-ft5x06, iforce, and cs40l50-vibra
 
 - Improvements to the synaptics-rmi4 driver to properly handle F54
   worker errors and prevent buffer overflows
 
 - Input validation fixes in the hynitron_cstxxx touchscreen driver to
   prevent issues with invalid finger IDs and touch counts
 
 - Fixes for use-after-free and initialization bugs in the byd mouse
   and psxpad-spi drivers
 
 - New quirks for the atkbd driver to make keyboard work on HONOR and
   Xiaomi laptops
 
 - Support for the ZENAIM LEVERLESS controller in the xpad driver.
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Merge tag 'input-for-v7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

Pull input updates from Dmitry Torokhov:

 - Fixes for information leaks and OOB accesses across several drivers,
   including evdev, focaltech, edt-ft5x06, iforce, and cs40l50-vibra

 - Improvements to the synaptics-rmi4 driver to properly handle F54
   worker errors and prevent buffer overflows

 - Input validation fixes in the hynitron_cstxxx touchscreen driver to
   prevent issues with invalid finger IDs and touch counts

 - Fixes for use-after-free and initialization bugs in the byd mouse and
   psxpad-spi drivers

 - New quirks for the atkbd driver to make keyboard work on HONOR and
   Xiaomi laptops

 - Support for the ZENAIM LEVERLESS controller in the xpad driver.

* tag 'input-for-v7.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: evdev - sanitize event type index when fetching event masks
  Input: synaptics-rmi4 - propagate F54 worker errors to V4L2 queue
  Input: synaptics-rmi4 - block s_input when F54 queue is busy
  Input: synaptics-rmi4 - bound the F54 report size to the allocated buffer
  Input: synaptics-rmi4 - zero report size on F54 work error
  Input: synaptics-rmi4 - fix F55 transmitter electrode count typo
  Input: hynitron_cstxxx - validate touch count and finger IDs
  Input: evdev - fix information leak in evdev_pass_values()
  fixp-arith: convert comments to kernel-doc format
  Input: focaltech - fix array out-of-bounds in focaltech_process_rel_packet
  Input: atkbd - skip deactivate for HONOR ZQC-P
  Input: atkbd - skip deactivate for Xiaomi Book Pro 14's internal keyboard
  Input: iforce - validate input packet lengths
  Input: psxpad-spi - set driver data before use
  Input: cs40l50-vibra - validate custom data from user space
  Input: xpad - add support for ZENAIM LEVERLESS
  Input: edt-ft5x06 - ignore contacts with an out-of-range slot id
  Input: byd - synchronize timer deletion before freeing private data
2026-08-08 07:09:35 -07:00
Linus Torvalds
afe80aebd3 powerpc fixes for 7.2 #4
- Couple of fixes for mem leak and underflow case
 
 Thanks to: George Wilson, R Nageswara Sastry
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Merge tag 'powerpc-7.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Madhavan Srinivasan:

 - A couple of fixes for a memory leak and a underflow case

Thanks to George Wilson and R Nageswara Sastry

* tag 'powerpc-7.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/pseries: lparcfg - fix kbuf[] underflow
  powerpc/pseries: pci - logic bug
  powerpc/pseries: papr-phy-attest - validate cmd.length, plug mem leak
2026-08-08 07:03:59 -07:00
Rik van Riel
e033cbf397 fbdev: bitblit: bound-check glyph index in bit_cursor()
bit_cursor() fetches the glyph under the cursor with

	c = scr_readw(vc_pos);
	src = vc_font.data + ((c & charmask) * w * height);

where charmask is 0x1ff when vc_hi_font_mask is set. The screen buffer
value comes directly from scr_readw() and may be larger than the current
font's glyph count.

Syzkaller triggers this via vcs_write(). The Call Trace shows
vcs_write() in vc_screen.c writing an arbitrary 16-bit value with
writev() to /dev/vcsa, which vcs_write_buf() in vc_screen.c stores via
vcs_scr_writew() without checking charcount. The stored value is later
read in bit_cursor() in bitblit.c.

When the font is changed from a font with 512 glyphs to a font with
256 glyphs, the screen buffer can retain characters with the high
bit set from the previous mode, which could also produce the same
out-of-bounds access.

  BUG: KASAN: global-out-of-bounds in soft_cursor+0x378/0x6bc drivers/video/fbdev/core/softcursor.c:70
  Read of size 16 at addr ffff800086c57970

  Call Trace:
   soft_cursor+0x378/0x6bc drivers/video/fbdev/core/softcursor.c:70
   bit_cursor+0xa90/0x1108 drivers/video/fbdev/core/bitblit.c:365
   fbcon_cursor+0x344/0x498 drivers/video/fbdev/core/fbcon.c:1427
   hide_cursor+0xdc/0x2d0 drivers/tty/vt/vt.c:883
   update_region+0x100/0x18c drivers/tty/vt/vt.c:669
   vcs_write+0x8ec/0xaf0 drivers/tty/vt/vc_screen.c:685

bit_putcs_aligned() and bit_putcs_unaligned() already clamp the glyph
index to vc_font.charcount. Apply the same clamp in bit_cursor() after
extracting the attribute and masking, before indexing fontdata.

The fix completes the bounds checking started in commit 18c4ef4e76
("fbdev: bitblit: bound-check glyph index in bit_putcs*"), which missed
the cursor path.

This change should be safe because the clamp reuses the existing
contract from fbcon: charcount is maintained under console_lock in
con_font_set() and fbcon_font_set(), and hi_font_mask is cleared when
switching from 512 to 256 glyphs. When stale screen data with high bits
remains after a font switch, or when vcs_write() stores an arbitrary
value, clamping the index to 0 prevents the out-of-bounds read without
changing cursor semantics — the same fallback bit_putcs uses.

Reported-by: syzbot+61b1db46218109869c14@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=61b1db46218109869c14
Link: https://lore.kernel.org/all/6a75205c.01d0871a.3a0d52.0032.GAE@google.com/
Fixes: 18c4ef4e76 ("fbdev: bitblit: bound-check glyph index in bit_putcs*")
Cc: stable@vger.kernel.org
Assisted-by: Hermes:muse-spark-1.2 syzkaller
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-08 08:08:58 +02:00
Zizhi Wo
ef7656e85f fbdev: Fix out-of-bounds access when rotating console after font resize
[BUG]
Recently, we encountered a KASAN warning as follows:

BUG: KASAN: slab-out-of-bounds in ccw_putcs+0x8bd/0xa80
Read of size 1 at addr ff11000110067100 by task bash/1209
CPU: 10 UID: 0 PID: 1209 Comm: bash Not tainted 7.2.0-rc3 #69 PREEMPT(full)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014
 Call Trace:
  <TASK>
  ...
  kasan_report+0xf0/0x120
  ? ccw_putcs+0x8bd/0xa80
  ccw_putcs+0x8bd/0xa80
  ? __pfx_ccw_putcs+0x10/0x10
  fbcon_putcs+0x338/0x410
  ? __pfx_ccw_putcs+0x10/0x10
  do_update_region+0x21d/0x450
  invert_screen+0x29d/0x5e0
  ? __kmalloc_noprof+0x493/0x640
  ? vc_do_resize+0x17c/0xe50
  clear_selection+0x4c/0x60
  vc_do_resize+0xaee/0xe50
  fbcon_modechanged+0x2bd/0x640
  rotate_all_store+0x298/0x380
  ...

reproduce:
1) issue two ioctls: first a KDFONTOP ioctl with op.op = KD_FONT_OP_SET,
op.width = 1 and op.height = 1, then a TIOCL_SETSEL ioctl
2) echo 2 > /sys/devices/virtual/graphics/fbcon/rotate_all
3) issue two ioctls: first a KDFONTOP ioctl with op.op = KD_FONT_OP_SET,
op.width = 8 and op.height = 1, then a TIOCL_SETSEL ioctl
4) echo 3 > /sys/devices/virtual/graphics/fbcon/rotate_all

[CAUSE]
The root cause is that fbcon_modechanged() first sets the current rotate's
corresponding ops. Subsequently, during vc_resize(), it may trigger
clear_selection(), and in fbcon_putcs->ccw_putcs[rotate=3], this can result
in an out-of-bounds access to "src". This happens because par->rotated.buf
is reallocated in fbcon_rotate_font():
1) When rotate=2, its size is (width + 7) / 8 * height
2) When rotate=3, its size is (height + 7) / 8 * width

And the call to fbcon_rotate_font() occurs after clear_selection(). In
other words, the fontbuffer is allocated using the size calculated from the
previous rotation 2, but before reallocating it with the new size,
con_putcs is already using the new rotation 3:

rotate_all_store
 fbcon_rotate_all
  fbcon_set_all_vcs
   fbcon_modechanged
    set_blitting_type
    ...
     par->bitops = &ccw_fbcon_bitops
    vc_resize
    ...
     clear_selection
      highlight
      ...
       do_update_region
	fbcon_putcs
	...
	 image.dy = vyres - ((xx + count) * vc->vc_font.width) [1]  // overflow!
	 ccw_putcs_aligned
	  // old buf size is still being used during the read!
	  src = par->rotated.buf + (scr_readw(s--) & charmask) * cellsize
	  fb_pad_aligned_buffer----[src KASAN!!!]	[2]
	  info->fbops->fb_imageblit(info, image)
	   sys_imageblit
	    fb_imageblit
	     fb_address_forward
	      // offset: image->dy * bits_per_line + image->dx * bpp
	      unsigned int bits = (unsigned int)adr->bits + offset
	      adr->address += (bits & ~(BITS_PER_LONG - 1u)) / BITS_PER_BYTE	[3]
	     fb_bitmap_imageblit
	     ...
	      fb_read_offset	// page fault!	[4]
    update_screen
     redraw_screen
     ...
      ccw_cursor
       soft_cursor
        memcpy(src, image->data, dsize)----[src KASAN again!!!]	[5]
     fbcon_switch
      fbcon_rotate_font
       font_data_rotate
	dst = kmalloc_array(charcount, d_cellsize, GFP_KERNEL)
       // the new size is allocated only here!
       par->rotated.buf = buf	[6]

[FIX]
A fairly obvious approach is to follow fbcon_switch(): in
fbcon_modechanged(), call rotate_font() before vc_resize() so that a
correctly sized buffer is allocated in time, as done in [6]. This fix is
necessary, but it is not sufficient on its own.

In [1] it causes an image.dy overflow (ccw_putcs: vyres = 768,
image.dy = 4294967040), because vc_cols has not been updated in time at
this point (it is likewise only updated after clear_selection()). This
allows (xx + count) * width to exceed vyres, causing image.dy to overflow.
Subsequently, address in [3] is incremented by an even larger amount, which
triggers a page fault at [4].

Therefore, a second fix is required in combination with the first: move
clear_selection() earlier, before set_blitting_type() in
fbcon_set_all_vcs(), to prevent the out-of-bounds access. fbcon_rotate()
has a similar problem, so add the same clear there. Since vc_is_sel() is
not exported, the fbdev side is currently forced to call clear_selection()
unconditionally, causing the global selection to be cleared prematurely.
And this will not cause any other significant impact.

Signed-off-by: Zizhi Wo <wozizhi@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-08 08:08:58 +02:00
Mingyu Wang
81cc73be40 fbdev: core: Fix pointer desynchronization in fb_io_read()
In fb_io_read(), if copy_to_user() performs a partial copy (e.g., due to
a faulty user buffer), the loop adjusts the chunk size 'c' and updates
the remaining 'count'. However, the hardware 'src' pointer has already
been eagerly advanced by the original chunk size.

If the loop is allowed to continue, the read will resume from an
incorrect, over-advanced offset. Since the remaining 'count' was only
decremented by the successful bytes, this desynchronization causes the
next iterations to execute more hardware reads than originally bounded,
eventually leading to out-of-bounds I/O reads.

Fix this by breaking out of the loop immediately upon a partial
copy_to_user(). A partial copy indicates a faulty user buffer, making
subsequent read attempts futile. Breaking out ensures we return the
number of successfully read bytes without risking out-of-bounds hardware
accesses in subsequent mismatched iterations.

Fixes: 6121cd9ef9 ("fbdev: Move I/O read and write code into helper functions")
Cc: stable@vger.kernel.org
Signed-off-by: Mingyu Wang <25181214217@stu.xidian.edu.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-08 08:08:58 +02:00
Melbin K Mathew
061db6b7a9 fbdev: serialize mode sysfs access with lock_fb_info()
show_mode(), show_modes(), and store_mode() access fb_info->modelist
and fb_info->mode without holding lock_fb_info(). store_modes() takes
lock_fb_info() while replacing the modelist and freeing the old one.

A concurrent reader or writer can load a pointer to an old modelist
entry before store_modes() frees it, then dereference freed memory or
store a stale freed pointer in fb_info->mode.

Take lock_fb_info() in show_mode(), show_modes(), and store_mode() to
serialize with store_modes(). In show_mode(), copy the mode to the
stack and format after dropping the lock. In store_mode(), split
activate() into a _locked variant to avoid double-locking, and hold
the locks for the modelist walk, mode conversion, activation, and
fb_info->mode assignment together.

Cc: stable@vger.kernel.org # v7.1+
Signed-off-by: Melbin K Mathew <mlbnkm1@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-08 08:08:58 +02:00
Melbin K Mathew
95e647d2a5 fbdev: clear fb_info->mode before deleting a videomode
fb_set_var() can delete a mode from info->modelist when userspace
passes FB_ACTIVATE_INV_MODE through FBIOPUT_VSCREENINFO. The code
checks that the mode being deleted is not the current info->var and
that fbcon is not using it, but it does not check fb_info->mode.

fb_info->mode may still point into the modelist entry being deleted.
If the entry is freed, later mode sysfs reads through show_mode() can
dereference a stale pointer.

Clear fb_info->mode before calling fb_delete_videomode() when it
matches the mode being removed.

Cc: stable@vger.kernel.org # v7.1+
Signed-off-by: Melbin K Mathew <mlbnkm1@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-08 08:08:58 +02:00
Melbin K Mathew
d15d51fb26 fbdev: bound mode sysfs output to the sysfs buffer
mode_string() uses snprintf() which can return a value larger than the
remaining buffer space. show_modes() accumulates the return value into i
without checking whether i has reached PAGE_SIZE, causing the offset to
advance past the sysfs buffer if the modelist is long enough.

Add a size parameter to mode_string() and use scnprintf() to return
only the bytes actually written. Add an early return when offset
already exceeds the buffer. In show_modes(), stop accumulating once
the buffer is full.

Cc: stable@vger.kernel.org # v7.1+
Signed-off-by: Melbin K Mathew <mlbnkm1@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-08-08 08:08:58 +02:00
George Wilson
fb442a6673 powerpc/pseries: lparcfg - fix kbuf[] underflow
In lparcfg_write(), a count of 0 results in kbuf[] being indexed at -1.
Check for count == 0 in the existing check for count > sizeof(kbuf) and
return -EINVAL if true.

Fixes: 74422e2b19 ("powerpc/pseries: Remove VLA from lparcfg_write()")
Acked-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: R Nageswara Sastry <rnsastry@linux.ibm.com>
Cc: stable@vger.kernel.org # 4.20
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
2026-08-08 10:34:28 +05:30
George Wilson
649c10bff5 powerpc/pseries: pci - logic bug
The checks on num_vfs in pseries_pci_sriov_enable() are ANDed where OR
was apparently intended.  Change it to OR.

Fixes: 9a7f6b4386 ("powerpc/pseries/pci: Associate PEs to VFs in configure SR-IOV")
Acked-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: R Nageswara Sastry <rnsastry@linux.ibm.com>
Cc: stable@vger.kernel.org # 4.16
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
2026-08-08 10:33:42 +05:30
George Wilson
5b17f3f343 powerpc/pseries: papr-phy-attest - validate cmd.length, plug mem leak
In papr_phy_attest_create_handle(), the params->cmd.length is not
validated before use, which can result in a buffer overlow.  Check it and
return -EINVAL if it is either 0 or exceeds sizeof(params->cmd).

Also, params is freed on the success path but not error. Free it on
errors after memory allocation.  And free it on negative fd.

Fixes: 86900ab620 ("powerpc/pseries: Add a char driver for physical-attestation RTAS")
Acked-by: Haren Myneni <haren@linux.ibm.com>
Acked-by: Nayna Jain <nayna@linux.ibm.com>
Tested-by: R Nageswara Sastry <rnsastry@linux.ibm.com>
Cc: stable@vger.kernel.org # 6.16
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
2026-08-08 10:32:26 +05:30
Linus Torvalds
a59f57e2aa watchdog fixes for v7.2-rc7
* at91sam9_wdt: prevent timer rearm during teardown
 
 * bd96801_wdt: Fix timeout for enabled WDG
 
 * atcwdt200: Fix return value when watchdog is enabled
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Merge tag 'watchdog-for-v7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull watchdog fixes from Guenter Roeck:

 - at91sam9_wdt: prevent timer rearm during teardown

 - bd96801_wdt: Fix timeout for enabled WDG

 - atcwdt200: Fix return value when watchdog is enabled

* tag 'watchdog-for-v7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  watchdog: at91sam9_wdt: prevent timer rearm during teardown
  watchdog: bd96801_wdt: Fix timeout for enabled WDG
  watchdog: atcwdt200: fix return value when watchdog is enabled
2026-08-07 17:29:59 -07:00
Linus Torvalds
5d78d199be hwmon fixes for v7.2-rc7
Various fixes, most of them fixing critical or high severity bugs
 reported by Sashiko.
 
 * ads7828
   - Fix external VREF regulator handling
 
 * corsair-psu
   - Fix linear11 calculation
   - Serialize debugfs access against hwmon
   - Fix possible out-of-bounds access on missing string termination
 
 * ltc4282
   - Fix parsing adi,current-limit-sense-microvolt
   - Clamp negative current limits
   - Avoid overflow in maximum power calculation
 
 * nzxt-smart2
   - Check return value of init_device() in probe
 
 * PMBus core
   - Fix type confusion in notification logic
   - Avoid race condition during probe
 
 * PMBus/lm25066
   - Fix PMBus coefficient calculations
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Merge tag 'hwmon-for-v7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:
 "Various fixes, most of them fixing critical or high severity bugs
  reported by Sashiko.

  ads7828:
   - Fix external VREF regulator handling

  corsair-psu:
   - Fix linear11 calculation
   - Serialize debugfs access against hwmon
   - Fix possible out-of-bounds access on missing string termination

  ltc4282:
   - Fix parsing adi,current-limit-sense-microvolt
   - Clamp negative current limits
   - Avoid overflow in maximum power calculation

  nzxt-smart2:
   - Check return value of init_device() in probe

  PMBus core:
   - Fix type confusion in notification logic
   - Avoid race condition during probe

  PMBus/lm25066:
   - Fix PMBus coefficient calculations"

* tag 'hwmon-for-v7.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (corsair-psu) Fix linear11 calculation
  hwmon: (corsair-psu) serialize debugfs access against hwmon
  hwmon: (ltc4282) Fix parsing adi,current-limit-sense-microvolt
  hwmon: (ltc4282) Clamp negative current limits
  hwmon: (ltc4282) Avoid overflow in maximum power calculation
  hwmon: (ads7828) Fix external VREF regulator handling
  hwmon: (corsair-psu) fix possible out-of-bounds access on missing string termination
  hwmon: (pmbus/lm25066) Fix PMBus coefficient calculations
  hwmon: (nzxt-smart2) Check return value of init_device() in probe
  hwmon: (pmbus) Fix type confusion in notification logic
  hwmon: (pmbus/core) Avoid race condition during probe
2026-08-07 17:14:05 -07:00