In the Linux kernel, the following vulnerability has been resolved:
hfsplus: remove mutex_lock check in hfsplus_free_extents
Syzbot reported an issue in hfsplus filesystem:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4400 at fs/hfsplus/extents.c:346
hfsplus_free_extents+0x700/0xad0
Call Trace:
<TASK>
hfsplus_file_truncate+0x768/0xbb0 fs/hfsplus/extents.c:606
hfsplus_write_begin+0xc2/0xd0 fs/hfsplus/inode.c:56
cont_expand_zero fs/buffer.c:2383 [inline]
cont_write_begin+0x2cf/0x860 fs/buffer.c:2446
hfsplus_write_begin+0x86/0xd0 fs/hfsplus/inode.c:52
generic_cont_expand_simple+0x151/0x250 fs/buffer.c:2347
hfsplus_setattr+0x168/0x280 fs/hfsplus/inode.c:263
notify_change+0xe38/0x10f0 fs/attr.c:420
do_truncate+0x1fb/0x2e0 fs/open.c:65
do_sys_ftruncate+0x2eb/0x380 fs/open.c:193
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
To avoid deadlock, Commit 31651c607151 ("hfsplus: avoid deadlock
on file truncation") unlock extree before hfsplus_free_extents(),
and add check wheather extree is locked in hfsplus_free_extents().
However, when operations such as hfsplus_file_release,
hfsplus_setattr, hfsplus_unlink, and hfsplus_get_block are executed
concurrently in different files, it is very likely to trigger the
WARN_ON, which will lead syzbot and xfstest to consider it as an
abnormality.
The comment above this warning also describes one of the easy
triggering situations, which can easily trigger and cause
xfstest&syzbot to report errors.
[task A] [task B]
->hfsplus_file_release
->hfsplus_file_truncate
->hfs_find_init
->mutex_lock
->mutex_unlock
->hfsplus_write_begin
->hfsplus_get_block
->hfsplus_file_extend
->hfsplus_ext_read_extent
->hfs_find_init
->mutex_lock
->hfsplus_free_extents
WARN_ON(mutex_is_locked) !!!
Several threads could try to lock the shared extents tree.
And warning can be triggered in one thread when another thread
has locked the tree. This is the wrong behavior of the code and
we need to remove the warning.
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: reject TDLS operations when station is not associated
syzbot triggered a WARN in ieee80211_tdls_oper() by sending
NL80211_TDLS_ENABLE_LINK immediately after NL80211_CMD_CONNECT,
before association completed and without prior TDLS setup.
This left internal state like sdata->u.mgd.tdls_peer uninitialized,
leading to a WARN_ON() in code paths that assumed it was valid.
Reject the operation early if not in station mode or not associated.
In the Linux kernel, the following vulnerability has been resolved:
clk: davinci: Add NULL check in davinci_lpsc_clk_register()
devm_kasprintf() returns NULL when memory allocation fails. Currently,
davinci_lpsc_clk_register() does not check for this case, which results
in a NULL pointer dereference.
Add NULL check after devm_kasprintf() to prevent this issue and ensuring
no resources are left allocated.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: xt_nfacct: don't assume acct name is null-terminated
BUG: KASAN: slab-out-of-bounds in .. lib/vsprintf.c:721
Read of size 1 at addr ffff88801eac95c8 by task syz-executor183/5851
[..]
string+0x231/0x2b0 lib/vsprintf.c:721
vsnprintf+0x739/0xf00 lib/vsprintf.c:2874
[..]
nfacct_mt_checkentry+0xd2/0xe0 net/netfilter/xt_nfacct.c:41
xt_check_match+0x3d1/0xab0 net/netfilter/x_tables.c:523
nfnl_acct_find_get() handles non-null input, but the error
printk relied on its presence.
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to trigger foreground gc during f2fs_map_blocks() in lfs mode
w/ "mode=lfs" mount option, generic/299 will cause system panic as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:2835!
Call Trace:
<TASK>
f2fs_allocate_data_block+0x6f4/0xc50
f2fs_map_blocks+0x970/0x1550
f2fs_iomap_begin+0xb2/0x1e0
iomap_iter+0x1d6/0x430
__iomap_dio_rw+0x208/0x9a0
f2fs_file_write_iter+0x6b3/0xfa0
aio_write+0x15d/0x2e0
io_submit_one+0x55e/0xab0
__x64_sys_io_submit+0xa5/0x230
do_syscall_64+0x84/0x2f0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0010:new_curseg+0x70f/0x720
The root cause of we run out-of-space is: in f2fs_map_blocks(), f2fs may
trigger foreground gc only if it allocates any physical block, it will be
a little bit later when there is multiple threads writing data w/
aio/dio/bufio method in parallel, since we always use OPU in lfs mode, so
f2fs_map_blocks() does block allocations aggressively.
In order to fix this issue, let's give a chance to trigger foreground
gc in prior to block allocation in f2fs_map_blocks().
In the Linux kernel, the following vulnerability has been resolved:
fbdev: imxfb: Check fb_add_videomode to prevent null-ptr-deref
fb_add_videomode() can fail with -ENOMEM when its internal kmalloc() cannot
allocate a struct fb_modelist. If that happens, the modelist stays empty but
the driver continues to register. Add a check for its return value to prevent
poteintial null-ptr-deref, which is similar to the commit 17186f1f90d3 ("fbdev:
Fix do_register_framebuffer to prevent null-ptr-deref in fb_videomode_to_var").
In the Linux kernel, the following vulnerability has been resolved:
PCI: pnv_php: Fix surprise plug detection and recovery
The existing PowerNV hotplug code did not handle surprise plug events
correctly, leading to a complete failure of the hotplug system after device
removal and a required reboot to detect new devices.
This comes down to two issues:
1) When a device is surprise removed, often the bridge upstream
port will cause a PE freeze on the PHB. If this freeze is not
cleared, the MSI interrupts from the bridge hotplug notification
logic will not be received by the kernel, stalling all plug events
on all slots associated with the PE.
2) When a device is removed from a slot, regardless of surprise or
programmatic removal, the associated PHB/PE ls left frozen.
If this freeze is not cleared via a fundamental reset, skiboot
is unable to clear the freeze and cannot retrain / rescan the
slot. This also requires a reboot to clear the freeze and redetect
the device in the slot.
Issue the appropriate unfreeze and rescan commands on hotplug events,
and don't oops on hotplug if pci_bus_to_OF_node() returns NULL.
[bhelgaas: tidy comments]
In the Linux kernel, the following vulnerability has been resolved:
PCI: pnv_php: Clean up allocated IRQs on unplug
When the root of a nested PCIe bridge configuration is unplugged, the
pnv_php driver leaked the allocated IRQ resources for the child bridges'
hotplug event notifications, resulting in a panic.
Fix this by walking all child buses and deallocating all its IRQ resources
before calling pci_hp_remove_devices().
Also modify the lifetime of the workqueue at struct pnv_php_slot::wq so
that it is only destroyed in pnv_php_free_slot(), instead of
pnv_php_disable_irq(). This is required since pnv_php_disable_irq() will
now be called by workers triggered by hot unplug interrupts, so the
workqueue needs to stay allocated.
The abridged kernel panic that occurs without this patch is as follows:
WARNING: CPU: 0 PID: 687 at kernel/irq/msi.c:292 msi_device_data_release+0x6c/0x9c
CPU: 0 UID: 0 PID: 687 Comm: bash Not tainted 6.14.0-rc5+ #2
Call Trace:
msi_device_data_release+0x34/0x9c (unreliable)
release_nodes+0x64/0x13c
devres_release_all+0xc0/0x140
device_del+0x2d4/0x46c
pci_destroy_dev+0x5c/0x194
pci_hp_remove_devices+0x90/0x128
pci_hp_remove_devices+0x44/0x128
pnv_php_disable_slot+0x54/0xd4
power_write_file+0xf8/0x18c
pci_slot_attr_store+0x40/0x5c
sysfs_kf_write+0x64/0x78
kernfs_fop_write_iter+0x1b0/0x290
vfs_write+0x3bc/0x50c
ksys_write+0x84/0x140
system_call_exception+0x124/0x230
system_call_vectored_common+0x15c/0x2ec
[bhelgaas: tidy comments]
In the Linux kernel, the following vulnerability has been resolved:
net/packet: fix a race in packet_set_ring() and packet_notifier()
When packet_set_ring() releases po->bind_lock, another thread can
run packet_notifier() and process an NETDEV_UP event.
This race and the fix are both similar to that of commit 15fe076edea7
("net/packet: fix a race in packet_bind() and packet_notifier()").
There too the packet_notifier NETDEV_UP event managed to run while a
po->bind_lock critical section had to be temporarily released. And
the fix was similarly to temporarily set po->num to zero to keep
the socket unhooked until the lock is retaken.
The po->bind_lock in packet_set_ring and packet_notifier precede the
introduction of git history.