In the Linux kernel, the following vulnerability has been resolved:
trace/fgraph: Fix the warning caused by missing unregister notifier
This warning was triggered during testing on v6.16:
notifier callback ftrace_suspend_notifier_call already registered
WARNING: CPU: 2 PID: 86 at kernel/notifier.c:23 notifier_chain_register+0x44/0xb0
...
Call Trace:
<TASK>
blocking_notifier_chain_register+0x34/0x60
register_ftrace_graph+0x330/0x410
ftrace_profile_write+0x1e9/0x340
vfs_write+0xf8/0x420
? filp_flush+0x8a/0xa0
? filp_close+0x1f/0x30
? do_dup2+0xaf/0x160
ksys_write+0x65/0xe0
do_syscall_64+0xa4/0x260
entry_SYSCALL_64_after_hwframe+0x77/0x7f
When writing to the function_profile_enabled interface, the notifier was
not unregistered after start_graph_tracing failed, causing a warning the
next time function_profile_enabled was written.
Fixed by adding unregister_pm_notifier in the exception path.
In the Linux kernel, the following vulnerability has been resolved:
net: rose: convert 'use' field to refcount_t
The 'use' field in struct rose_neigh is used as a reference counter but
lacks atomicity. This can lead to race conditions where a rose_neigh
structure is freed while still being referenced by other code paths.
For example, when rose_neigh->use becomes zero during an ioctl operation
via rose_rt_ioctl(), the structure may be removed while its timer is
still active, potentially causing use-after-free issues.
This patch changes the type of 'use' from unsigned short to refcount_t and
updates all code paths to use rose_neigh_hold() and rose_neigh_put() which
operate reference counts atomically.
In the Linux kernel, the following vulnerability has been resolved:
net: rose: include node references in rose_neigh refcount
Current implementation maintains two separate reference counting
mechanisms: the 'count' field in struct rose_neigh tracks references from
rose_node structures, while the 'use' field (now refcount_t) tracks
references from rose_sock.
This patch merges these two reference counting systems using 'use' field
for proper reference management. Specifically, this patch adds incrementing
and decrementing of rose_neigh->use when rose_neigh->count is incremented
or decremented.
This patch also modifies rose_rt_free(), rose_rt_device_down() and
rose_clear_route() to properly release references to rose_neigh objects
before freeing a rose_node through rose_remove_node().
These changes ensure rose_neigh structures are properly freed only when
all references, including those from rose_node structures, are released.
As a result, this resolves a slab-use-after-free issue reported by Syzbot.
In the Linux kernel, the following vulnerability has been resolved:
fs/smb: Fix inconsistent refcnt update
A possible inconsistent update of refcount was identified in `smb2_compound_op`.
Such inconsistent update could lead to possible resource leaks.
Why it is a possible bug:
1. In the comment section of the function, it clearly states that the
reference to `cfile` should be dropped after calling this function.
2. Every control flow path would check and drop the reference to
`cfile`, except the patched one.
3. Existing callers would not handle refcount update of `cfile` if
-ENOMEM is returned.
To fix the bug, an extra goto label "out" is added, to make sure that the
cleanup logic would always be respected. As the problem is caused by the
allocation failure of `vars`, the cleanup logic between label "finished"
and "out" can be safely ignored. According to the definition of function
`is_replayable_error`, the error code of "-ENOMEM" is not recoverable.
Therefore, the replay logic also gets ignored.
In the Linux kernel, the following vulnerability has been resolved:
bnxt_en: Fix memory corruption when FW resources change during ifdown
bnxt_set_dflt_rings() assumes that it is always called before any TC has
been created. So it doesn't take bp->num_tc into account and assumes
that it is always 0 or 1.
In the FW resource or capability change scenario, the FW will return
flags in bnxt_hwrm_if_change() that will cause the driver to
reinitialize and call bnxt_cancel_reservations(). This will lead to
bnxt_init_dflt_ring_mode() calling bnxt_set_dflt_rings() and bp->num_tc
may be greater than 1. This will cause bp->tx_ring[] to be sized too
small and cause memory corruption in bnxt_alloc_cp_rings().
Fix it by properly scaling the TX rings by bp->num_tc in the code
paths mentioned above. Add 2 helper functions to determine
bp->tx_nr_rings and bp->tx_nr_rings_per_tc.
In the Linux kernel, the following vulnerability has been resolved:
blk-mq: fix NULL dereference on q->elevator in blk_mq_elv_switch_none
After grabbing q->sysfs_lock, q->elevator may become NULL because of
elevator switch.
Fix the NULL dereference on q->elevator by checking it with lock.
In the Linux kernel, the following vulnerability has been resolved:
scsi: lpfc: Fix use-after-free KFENCE violation during sysfs firmware write
During the sysfs firmware write process, a use-after-free read warning is
logged from the lpfc_wr_object() routine:
BUG: KFENCE: use-after-free read in lpfc_wr_object+0x235/0x310 [lpfc]
Use-after-free read at 0x0000000000cf164d (in kfence-#111):
lpfc_wr_object+0x235/0x310 [lpfc]
lpfc_write_firmware.cold+0x206/0x30d [lpfc]
lpfc_sli4_request_firmware_update+0xa6/0x100 [lpfc]
lpfc_request_firmware_upgrade_store+0x66/0xb0 [lpfc]
kernfs_fop_write_iter+0x121/0x1b0
new_sync_write+0x11c/0x1b0
vfs_write+0x1ef/0x280
ksys_write+0x5f/0xe0
do_syscall_64+0x59/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
The driver accessed wr_object pointer data, which was initialized into
mailbox payload memory, after the mailbox object was released back to the
mailbox pool.
Fix by moving the mailbox free calls to the end of the routine ensuring
that we don't reference internal mailbox memory after release.
In the Linux kernel, the following vulnerability has been resolved:
usb: cdns3: Put the cdns set active part outside the spin lock
The device may be scheduled during the resume process,
so this cannot appear in atomic operations. Since
pm_runtime_set_active will resume suppliers, put set
active outside the spin lock, which is only used to
protect the struct cdns data structure, otherwise the
kernel will report the following warning:
BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:1163
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 651, name: sh
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
CPU: 0 PID: 651 Comm: sh Tainted: G WC 6.1.20 #1
Hardware name: Freescale i.MX8QM MEK (DT)
Call trace:
dump_backtrace.part.0+0xe0/0xf0
show_stack+0x18/0x30
dump_stack_lvl+0x64/0x80
dump_stack+0x1c/0x38
__might_resched+0x1fc/0x240
__might_sleep+0x68/0xc0
__pm_runtime_resume+0x9c/0xe0
rpm_get_suppliers+0x68/0x1b0
__pm_runtime_set_status+0x298/0x560
cdns_resume+0xb0/0x1c0
cdns3_controller_resume.isra.0+0x1e0/0x250
cdns3_plat_resume+0x28/0x40
In the Linux kernel, the following vulnerability has been resolved:
misc: vmw_balloon: fix memory leak with using debugfs_lookup()
When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time. To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic at
once.
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix i_disksize exceeding i_size problem in paritally written case
It is possible for i_disksize can exceed i_size, triggering a warning.
generic_perform_write
copied = iov_iter_copy_from_user_atomic(len) // copied < len
ext4_da_write_end
| ext4_update_i_disksize
| new_i_size = pos + copied;
| WRITE_ONCE(EXT4_I(inode)->i_disksize, newsize) // update i_disksize
| generic_write_end
| copied = block_write_end(copied, len) // copied = 0
| if (unlikely(copied < len))
| if (!PageUptodate(page))
| copied = 0;
| if (pos + copied > inode->i_size) // return false
if (unlikely(copied == 0))
goto again;
if (unlikely(iov_iter_fault_in_readable(i, bytes))) {
status = -EFAULT;
break;
}
We get i_disksize greater than i_size here, which could trigger WARNING
check 'i_size_read(inode) < EXT4_I(inode)->i_disksize' while doing dio:
ext4_dio_write_iter
iomap_dio_rw
__iomap_dio_rw // return err, length is not aligned to 512
ext4_handle_inode_extension
WARN_ON_ONCE(i_size_read(inode) < EXT4_I(inode)->i_disksize) // Oops
WARNING: CPU: 2 PID: 2609 at fs/ext4/file.c:319
CPU: 2 PID: 2609 Comm: aa Not tainted 6.3.0-rc2
RIP: 0010:ext4_file_write_iter+0xbc7
Call Trace:
vfs_write+0x3b1
ksys_write+0x77
do_syscall_64+0x39
Fix it by updating 'copied' value before updating i_disksize just like
ext4_write_inline_data_end() does.
A reproducer can be found in the buganizer link below.