In the Linux kernel, the following vulnerability has been resolved:
net/smc: fix NULL sndbuf_desc in smc_cdc_tx_handler()
When performing a stress test on SMC-R by rmmod mlx5_ib driver
during the wrk/nginx test, we found that there is a probability
of triggering a panic while terminating all link groups.
This issue dues to the race between smc_smcr_terminate_all()
and smc_buf_create().
smc_smcr_terminate_all
smc_buf_create
/* init */
conn->sndbuf_desc = NULL;
...
__smc_lgr_terminate
smc_conn_kill
smc_close_abort
smc_cdc_get_slot_and_msg_send
__softirqentry_text_start
smc_wr_tx_process_cqe
smc_cdc_tx_handler
READ(conn->sndbuf_desc->len);
/* panic dues to NULL sndbuf_desc */
conn->sndbuf_desc = xxx;
This patch tries to fix the issue by always to check the sndbuf_desc
before send any cdc msg, to make sure that no null pointer is
seen during cqe processing.
In the Linux kernel, the following vulnerability has been resolved:
ext4: update s_journal_inum if it changes after journal replay
When mounting a crafted ext4 image, s_journal_inum may change after journal
replay, which is obviously unreasonable because we have successfully loaded
and replayed the journal through the old s_journal_inum. And the new
s_journal_inum bypasses some of the checks in ext4_get_journal(), which
may trigger a null pointer dereference problem. So if s_journal_inum
changes after the journal replay, we ignore the change, and rewrite the
current journal_inum to the superblock.
In the Linux kernel, the following vulnerability has been resolved:
tty: serial: fsl_lpuart: fix race on RX DMA shutdown
From time to time DMA completion can come in the middle of DMA shutdown:
<process ctx>: <IRQ>:
lpuart32_shutdown()
lpuart_dma_shutdown()
del_timer_sync()
lpuart_dma_rx_complete()
lpuart_copy_rx_to_tty()
mod_timer()
lpuart_dma_rx_free()
When the timer fires a bit later, sport->dma_rx_desc is NULL:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004
pc : lpuart_copy_rx_to_tty+0xcc/0x5bc
lr : lpuart_timer_func+0x1c/0x2c
Call trace:
lpuart_copy_rx_to_tty
lpuart_timer_func
call_timer_fn
__run_timers.part.0
run_timer_softirq
__do_softirq
__irq_exit_rcu
irq_exit
handle_domain_irq
gic_handle_irq
call_on_irq_stack
do_interrupt_handler
...
To fix this fold del_timer_sync() into lpuart_dma_rx_free() after
dmaengine_terminate_sync() to make sure timer will not be re-started in
lpuart_copy_rx_to_tty() <= lpuart_dma_rx_complete().
In the Linux kernel, the following vulnerability has been resolved:
interconnect: fix mem leak when freeing nodes
The node link array is allocated when adding links to a node but is not
deallocated when nodes are destroyed.
In the Linux kernel, the following vulnerability has been resolved:
powerpc/iommu: 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:
xsk: Add missing overflow check in xdp_umem_reg
The number of chunks can overflow u32. Make sure to return -EINVAL on
overflow. Also remove a redundant u32 cast assigning umem->npgs.
In the Linux kernel, the following vulnerability has been resolved:
drm/i915/active: Fix misuse of non-idle barriers as fence trackers
Users reported oopses on list corruptions when using i915 perf with a
number of concurrently running graphics applications. Root cause analysis
pointed at an issue in barrier processing code -- a race among perf open /
close replacing active barriers with perf requests on kernel context and
concurrent barrier preallocate / acquire operations performed during user
context first pin / last unpin.
When adding a request to a composite tracker, we try to reuse an existing
fence tracker, already allocated and registered with that composite. The
tracker we obtain may already track another fence, may be an idle barrier,
or an active barrier.
If the tracker we get occurs a non-idle barrier then we try to delete that
barrier from a list of barrier tasks it belongs to. However, while doing
that we don't respect return value from a function that performs the
barrier deletion. Should the deletion ever fail, we would end up reusing
the tracker still registered as a barrier task. Since the same structure
field is reused with both fence callback lists and barrier tasks list,
list corruptions would likely occur.
Barriers are now deleted from a barrier tasks list by temporarily removing
the list content, traversing that content with skip over the node to be
deleted, then populating the list back with the modified content. Should
that intentionally racy concurrent deletion attempts be not serialized,
one or more of those may fail because of the list being temporary empty.
Related code that ignores the results of barrier deletion was initially
introduced in v5.4 by commit d8af05ff38ae ("drm/i915: Allow sharing the
idle-barrier from other kernel requests"). However, all users of the
barrier deletion routine were apparently serialized at that time, then the
issue didn't exhibit itself. Results of git bisect with help of a newly
developed igt@gem_barrier_race@remote-request IGT test indicate that list
corruptions might start to appear after commit 311770173fac ("drm/i915/gt:
Schedule request retirement when timeline idles"), introduced in v5.5.
Respect results of barrier deletion attempts -- mark the barrier as idle
only if successfully deleted from the list. Then, before proceeding with
setting our fence as the one currently tracked, make sure that the tracker
we've got is not a non-idle barrier. If that check fails then don't use
that tracker but go back and try to acquire a new, usable one.
v3: use unlikely() to document what outcome we expect (Andi),
- fix bad grammar in commit description.
v2: no code changes,
- blame commit 311770173fac ("drm/i915/gt: Schedule request retirement
when timeline idles"), v5.5, not commit d8af05ff38ae ("drm/i915: Allow
sharing the idle-barrier from other kernel requests"), v5.4,
- reword commit description.
(cherry picked from commit 506006055769b10d1b2b4e22f636f3b45e0e9fc7)