In the Linux kernel, the following vulnerability has been resolved:
media: pci: tw68: Fix null-ptr-deref bug in buf prepare and finish
When the driver calls tw68_risc_buffer() to prepare the buffer, the
function call dma_alloc_coherent may fail, resulting in a empty buffer
buf->cpu. Later when we free the buffer or access the buffer, null ptr
deref is triggered.
This bug is similar to the following one:
https://git.linuxtv.org/media_stage.git/commit/?id=2b064d91440b33fba5b452f2d1b31f13ae911d71.
We believe the bug can be also dynamically triggered from user side.
Similarly, we fix this by checking the return value of tw68_risc_buffer()
and the value of buf->cpu before buffer free.
In the Linux kernel, the following vulnerability has been resolved:
btrfs: set_page_extent_mapped after read_folio in btrfs_cont_expand
While trying to get the subpage blocksize tests running, I hit the
following panic on generic/476
assertion failed: PagePrivate(page) && page->private, in fs/btrfs/subpage.c:229
kernel BUG at fs/btrfs/subpage.c:229!
Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
CPU: 1 PID: 1453 Comm: fsstress Not tainted 6.4.0-rc7+ #12
Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20230301gitf80f052277c8-26.fc38 03/01/2023
pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : btrfs_subpage_assert+0xbc/0xf0
lr : btrfs_subpage_assert+0xbc/0xf0
Call trace:
btrfs_subpage_assert+0xbc/0xf0
btrfs_subpage_clear_checked+0x38/0xc0
btrfs_page_clear_checked+0x48/0x98
btrfs_truncate_block+0x5d0/0x6a8
btrfs_cont_expand+0x5c/0x528
btrfs_write_check.isra.0+0xf8/0x150
btrfs_buffered_write+0xb4/0x760
btrfs_do_write_iter+0x2f8/0x4b0
btrfs_file_write_iter+0x1c/0x30
do_iter_readv_writev+0xc8/0x158
do_iter_write+0x9c/0x210
vfs_iter_write+0x24/0x40
iter_file_splice_write+0x224/0x390
direct_splice_actor+0x38/0x68
splice_direct_to_actor+0x12c/0x260
do_splice_direct+0x90/0xe8
generic_copy_file_range+0x50/0x90
vfs_copy_file_range+0x29c/0x470
__arm64_sys_copy_file_range+0xcc/0x498
invoke_syscall.constprop.0+0x80/0xd8
do_el0_svc+0x6c/0x168
el0_svc+0x50/0x1b0
el0t_64_sync_handler+0x114/0x120
el0t_64_sync+0x194/0x198
This happens because during btrfs_cont_expand we'll get a page, set it
as mapped, and if it's not Uptodate we'll read it. However between the
read and re-locking the page we could have called release_folio() on the
page, but left the page in the file mapping. release_folio() can clear
the page private, and thus further down we blow up when we go to modify
the subpage bits.
Fix this by putting the set_page_extent_mapped() after the read. This
is safe because read_folio() will call set_page_extent_mapped() before
it does the read, and then if we clear page private but leave it on the
mapping we're completely safe re-setting set_page_extent_mapped(). With
this patch I can now run generic/476 without panicing.
In the Linux kernel, the following vulnerability has been resolved:
spi: imx: Don't skip cleanup in remove's error path
Returning early in a platform driver's remove callback is wrong. In this
case the dma resources are not released in the error path. this is never
retried later and so this is a permanent leak. To fix this, only skip
hardware disabling if waking the device fails.
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix warning in cifs_smb3_do_mount()
This fixes the following warning reported by kernel test robot
fs/smb/client/cifsfs.c:982 cifs_smb3_do_mount() warn: possible
memory leak of 'cifs_sb'
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Make it so that a waiting process can be aborted
When sendmsg() creates an rxrpc call, it queues it to wait for a connection
and channel to be assigned and then waits before it can start shovelling
data as the encrypted DATA packet content includes a summary of the
connection parameters.
However, sendmsg() may get interrupted before a connection gets assigned
and further sendmsg() calls will fail with EBUSY until an assignment is
made.
Fix this so that the call can at least be aborted without failing on
EBUSY. We have to be careful here as sendmsg() mustn't be allowed to start
the call timer if the call doesn't yet have a connection assigned as an
oops may follow shortly thereafter.
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211_hwsim: Fix possible NULL dereference
In a call to mac80211_hwsim_select_tx_link() the sta pointer might
be NULL, thus need to check that it is not NULL before accessing it.
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath9k: hif_usb: clean up skbs if ath9k_hif_usb_rx_stream() fails
Syzkaller detected a memory leak of skbs in ath9k_hif_usb_rx_stream().
While processing skbs in ath9k_hif_usb_rx_stream(), the already allocated
skbs in skb_pool are not freed if ath9k_hif_usb_rx_stream() fails. If we
have an incorrect pkt_len or pkt_tag, the input skb is considered invalid
and dropped. All the associated packets already in skb_pool should be
dropped and freed. Added a comment describing this issue.
The patch also makes remain_skb NULL after being processed so that it
cannot be referenced after potential free. The initialization of hif_dev
fields which are associated with remain_skb (rx_remain_len,
rx_transfer_len and rx_pad_len) is moved after a new remain_skb is
allocated.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: x_tables: fix percpu counter block leak on error path when creating new netns
Here is the stack where we allocate percpu counter block:
+-< __alloc_percpu
+-< xt_percpu_counter_alloc
+-< find_check_entry # {arp,ip,ip6}_tables.c
+-< translate_table
And it can be leaked on this code path:
+-> ip6t_register_table
+-> translate_table # allocates percpu counter block
+-> xt_register_table # fails
there is no freeing of the counter block on xt_register_table fail.
Note: xt_percpu_counter_free should be called to free it like we do in
do_replace through cleanup_entry helper (or in __ip6t_unregister_table).
Probability of hitting this error path is low AFAICS (xt_register_table
can only return ENOMEM here, as it is not replacing anything, as we are
creating new netns, and it is hard to imagine that all previous
allocations succeeded and after that one in xt_register_table failed).
But it's worth fixing even the rare leak.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/bnxt_re: wraparound mbox producer index
Driver is not handling the wraparound of the mbox producer index correctly.
Currently the wraparound happens once u32 max is reached.
Bit 31 of the producer index register is special and should be set
only once for the first command. Because the producer index overflow
setting bit31 after a long time, FW goes to initialization sequence
and this causes FW hang.
Fix is to wraparound the mbox producer index once it reaches u16 max.
In the Linux kernel, the following vulnerability has been resolved:
hugetlbfs: fix null-ptr-deref in hugetlbfs_parse_param()
Syzkaller reports a null-ptr-deref bug as follows:
======================================================
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:hugetlbfs_parse_param+0x1dd/0x8e0 fs/hugetlbfs/inode.c:1380
[...]
Call Trace:
<TASK>
vfs_parse_fs_param fs/fs_context.c:148 [inline]
vfs_parse_fs_param+0x1f9/0x3c0 fs/fs_context.c:129
vfs_parse_fs_string+0xdb/0x170 fs/fs_context.c:191
generic_parse_monolithic+0x16f/0x1f0 fs/fs_context.c:231
do_new_mount fs/namespace.c:3036 [inline]
path_mount+0x12de/0x1e20 fs/namespace.c:3370
do_mount fs/namespace.c:3383 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__x64_sys_mount+0x27f/0x300 fs/namespace.c:3568
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
[...]
</TASK>
======================================================
According to commit "vfs: parse: deal with zero length string value",
kernel will set the param->string to null pointer in vfs_parse_fs_string()
if fs string has zero length.
Yet the problem is that, hugetlbfs_parse_param() will dereference the
param->string, without checking whether it is a null pointer. To be more
specific, if hugetlbfs_parse_param() parses an illegal mount parameter,
such as "size=,", kernel will constructs struct fs_parameter with null
pointer in vfs_parse_fs_string(), then passes this struct fs_parameter to
hugetlbfs_parse_param(), which triggers the above null-ptr-deref bug.
This patch solves it by adding sanity check on param->string
in hugetlbfs_parse_param().