In the Linux kernel, the following vulnerability has been resolved:
btrfs: reinitialize delayed ref list after deleting it from the list
At insert_delayed_ref() if we need to update the action of an existing
ref to BTRFS_DROP_DELAYED_REF, we delete the ref from its ref head's
ref_add_list using list_del(), which leaves the ref's add_list member
not reinitialized, as list_del() sets the next and prev members of the
list to LIST_POISON1 and LIST_POISON2, respectively.
If later we end up calling drop_delayed_ref() against the ref, which can
happen during merging or when destroying delayed refs due to a transaction
abort, we can trigger a crash since at drop_delayed_ref() we call
list_empty() against the ref's add_list, which returns false since
the list was not reinitialized after the list_del() and as a consequence
we call list_del() again at drop_delayed_ref(). This results in an
invalid list access since the next and prev members are set to poison
pointers, resulting in a splat if CONFIG_LIST_HARDENED and
CONFIG_DEBUG_LIST are set or invalid poison pointer dereferences
otherwise.
So fix this by deleting from the list with list_del_init() instead.
In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: Initialization of the dangling pointer occurring in vsk->trans
During loopback communication, a dangling pointer can be created in
vsk->trans, potentially leading to a Use-After-Free condition. This
issue is resolved by initializing vsk->trans to NULL.
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: remove entry once instead of null-ptr-dereference in ocfs2_xa_remove()
Syzkaller is able to provoke null-ptr-dereference in ocfs2_xa_remove():
[ 57.319872] (a.out,1161,7):ocfs2_xa_remove:2028 ERROR: status = -12
[ 57.320420] (a.out,1161,7):ocfs2_xa_cleanup_value_truncate:1999 ERROR: Partial truncate while removing xattr overlay.upper. Leaking 1 clusters and removing the entry
[ 57.321727] BUG: kernel NULL pointer dereference, address: 0000000000000004
[...]
[ 57.325727] RIP: 0010:ocfs2_xa_block_wipe_namevalue+0x2a/0xc0
[...]
[ 57.331328] Call Trace:
[ 57.331477] <TASK>
[...]
[ 57.333511] ? do_user_addr_fault+0x3e5/0x740
[ 57.333778] ? exc_page_fault+0x70/0x170
[ 57.334016] ? asm_exc_page_fault+0x2b/0x30
[ 57.334263] ? __pfx_ocfs2_xa_block_wipe_namevalue+0x10/0x10
[ 57.334596] ? ocfs2_xa_block_wipe_namevalue+0x2a/0xc0
[ 57.334913] ocfs2_xa_remove_entry+0x23/0xc0
[ 57.335164] ocfs2_xa_set+0x704/0xcf0
[ 57.335381] ? _raw_spin_unlock+0x1a/0x40
[ 57.335620] ? ocfs2_inode_cache_unlock+0x16/0x20
[ 57.335915] ? trace_preempt_on+0x1e/0x70
[ 57.336153] ? start_this_handle+0x16c/0x500
[ 57.336410] ? preempt_count_sub+0x50/0x80
[ 57.336656] ? _raw_read_unlock+0x20/0x40
[ 57.336906] ? start_this_handle+0x16c/0x500
[ 57.337162] ocfs2_xattr_block_set+0xa6/0x1e0
[ 57.337424] __ocfs2_xattr_set_handle+0x1fd/0x5d0
[ 57.337706] ? ocfs2_start_trans+0x13d/0x290
[ 57.337971] ocfs2_xattr_set+0xb13/0xfb0
[ 57.338207] ? dput+0x46/0x1c0
[ 57.338393] ocfs2_xattr_trusted_set+0x28/0x30
[ 57.338665] ? ocfs2_xattr_trusted_set+0x28/0x30
[ 57.338948] __vfs_removexattr+0x92/0xc0
[ 57.339182] __vfs_removexattr_locked+0xd5/0x190
[ 57.339456] ? preempt_count_sub+0x50/0x80
[ 57.339705] vfs_removexattr+0x5f/0x100
[...]
Reproducer uses faultinject facility to fail ocfs2_xa_remove() ->
ocfs2_xa_value_truncate() with -ENOMEM.
In this case the comment mentions that we can return 0 if
ocfs2_xa_cleanup_value_truncate() is going to wipe the entry
anyway. But the following 'rc' check is wrong and execution flow do
'ocfs2_xa_remove_entry(loc);' twice:
* 1st: in ocfs2_xa_cleanup_value_truncate();
* 2nd: returning back to ocfs2_xa_remove() instead of going to 'out'.
Fix this by skipping the 2nd removal of the same entry and making
syzkaller repro happy.
In the Linux kernel, the following vulnerability has been resolved:
USB: serial: io_edgeport: fix use after free in debug printk
The "dev_dbg(&urb->dev->dev, ..." which happens after usb_free_urb(urb)
is a use after free of the "urb" pointer. Store the "dev" pointer at the
start of the function to avoid this issue.
In the Linux kernel, the following vulnerability has been resolved:
usb: musb: sunxi: Fix accessing an released usb phy
Commit 6ed05c68cbca ("usb: musb: sunxi: Explicitly release USB PHY on
exit") will cause that usb phy @glue->xceiv is accessed after released.
1) register platform driver @sunxi_musb_driver
// get the usb phy @glue->xceiv
sunxi_musb_probe() -> devm_usb_get_phy().
2) register and unregister platform driver @musb_driver
musb_probe() -> sunxi_musb_init()
use the phy here
//the phy is released here
musb_remove() -> sunxi_musb_exit() -> devm_usb_put_phy()
3) register @musb_driver again
musb_probe() -> sunxi_musb_init()
use the phy here but the phy has been released at 2).
...
Fixed by reverting the commit, namely, removing devm_usb_put_phy()
from sunxi_musb_exit().
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: fix possible UAF in amdgpu_cs_pass1()
Since the gang_size check is outside of chunk parsing
loop, we need to reset i before we free the chunk data.
Suggested by Ye Zhang (@VAR10CK) of Baidu Security.
A flaw was found within the parsing of extended attributes in the kernel ksmbd module. The issue results from the lack of proper validation of user-supplied data, which can result in a read past the end of an allocated buffer. An attacker can leverage this to disclose sensitive information on affected installations of Linux. Only systems with ksmbd enabled are vulnerable to this CVE.
A use-after-free vulnerability was found in the cyttsp4_core driver in the Linux kernel. This issue occurs in the device cleanup routine due to a possible rearming of the watchdog_timer from the workqueue. This could allow a local user to crash the system, causing a denial of service.
In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: Fix general protection fault in run_is_mapped_full
Fixed deleating of a non-resident attribute in ntfs_create_inode()
rollback.