In the Linux kernel, the following vulnerability has been resolved:
ALSA: ac97: Fix possible NULL dereference in snd_ac97_mixer
smatch error:
sound/pci/ac97/ac97_codec.c:2354 snd_ac97_mixer() error:
we previously assumed 'rac97' could be null (see line 2072)
remove redundant assignment, return error if rac97 is NULL.
In the Linux kernel, the following vulnerability has been resolved:
fbdev: omapfb: lcd_mipid: Fix an error handling path in mipid_spi_probe()
If 'mipid_detect()' fails, we must free 'md' to avoid a memory leak.
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath9k: hif_usb: fix memory leak of remain_skbs
hif_dev->remain_skb is allocated and used exclusively in
ath9k_hif_usb_rx_stream(). It is implied that an allocated remain_skb is
processed and subsequently freed (in error paths) only during the next
call of ath9k_hif_usb_rx_stream().
So, if the urbs are deallocated between those two calls due to the device
deinitialization or suspend, it is possible that ath9k_hif_usb_rx_stream()
is not called next time and the allocated remain_skb is leaked. Our local
Syzkaller instance was able to trigger that.
remain_skb makes sense when receiving two consecutive urbs which are
logically linked together, i.e. a specific data field from the first skb
indicates a cached skb to be allocated, memcpy'd with some data and
subsequently processed in the next call to ath9k_hif_usb_rx_stream(). Urbs
deallocation supposedly makes that link irrelevant so we need to free the
cached skb in those cases.
Fix the leak by introducing a function to explicitly free remain_skb (if
it is not NULL) when the rx urbs have been deallocated. remain_skb is NULL
when it has not been allocated at all (hif_dev struct is kzalloced) or
when it has been processed in next call to ath9k_hif_usb_rx_stream().
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
In the Linux kernel, the following vulnerability has been resolved:
md: fix soft lockup in status_resync
status_resync() will calculate 'curr_resync - recovery_active' to show
user a progress bar like following:
[============>........] resync = 61.4%
'curr_resync' and 'recovery_active' is updated in md_do_sync(), and
status_resync() can read them concurrently, hence it's possible that
'curr_resync - recovery_active' can overflow to a huge number. In this
case status_resync() will be stuck in the loop to print a large amount
of '=', which will end up soft lockup.
Fix the problem by setting 'resync' to MD_RESYNC_ACTIVE in this case,
this way resync in progress will be reported to user.
In the Linux kernel, the following vulnerability has been resolved:
gfs2: Fix possible data races in gfs2_show_options()
Some fields such as gt_logd_secs of the struct gfs2_tune are accessed
without holding the lock gt_spin in gfs2_show_options():
val = sdp->sd_tune.gt_logd_secs;
if (val != 30)
seq_printf(s, ",commit=%d", val);
And thus can cause data races when gfs2_show_options() and other functions
such as gfs2_reconfigure() are concurrently executed:
spin_lock(>->gt_spin);
gt->gt_logd_secs = newargs->ar_commit;
To fix these possible data races, the lock sdp->sd_tune.gt_spin is
acquired before accessing the fields of gfs2_tune and released after these
accesses.
Further changes by Andreas:
- Don't hold the spin lock over the seq_printf operations.
In the Linux kernel, the following vulnerability has been resolved:
usb: host: xhci: Fix potential memory leak in xhci_alloc_stream_info()
xhci_alloc_stream_info() allocates stream context array for stream_info
->stream_ctx_array with xhci_alloc_stream_ctx(). When some error occurs,
stream_info->stream_ctx_array is not released, which will lead to a
memory leak.
We can fix it by releasing the stream_info->stream_ctx_array with
xhci_free_stream_ctx() on the error path to avoid the potential memory
leak.
In the Linux kernel, the following vulnerability has been resolved:
r6040: Fix kmemleak in probe and remove
There is a memory leaks reported by kmemleak:
unreferenced object 0xffff888116111000 (size 2048):
comm "modprobe", pid 817, jiffies 4294759745 (age 76.502s)
hex dump (first 32 bytes):
00 c4 0a 04 81 88 ff ff 08 10 11 16 81 88 ff ff ................
08 10 11 16 81 88 ff ff 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff815bcd82>] kmalloc_trace+0x22/0x60
[<ffffffff827e20ee>] phy_device_create+0x4e/0x90
[<ffffffff827e6072>] get_phy_device+0xd2/0x220
[<ffffffff827e7844>] mdiobus_scan+0xa4/0x2e0
[<ffffffff827e8be2>] __mdiobus_register+0x482/0x8b0
[<ffffffffa01f5d24>] r6040_init_one+0x714/0xd2c [r6040]
...
The problem occurs in probe process as follows:
r6040_init_one:
mdiobus_register
mdiobus_scan <- alloc and register phy_device,
the reference count of phy_device is 3
r6040_mii_probe
phy_connect <- connect to the first phy_device,
so the reference count of the first
phy_device is 4, others are 3
register_netdev <- fault inject succeeded, goto error handling path
// error handling path
err_out_mdio_unregister:
mdiobus_unregister(lp->mii_bus);
err_out_mdio:
mdiobus_free(lp->mii_bus); <- the reference count of the first
phy_device is 1, it is not released
and other phy_devices are released
// similarly, the remove process also has the same problem
The root cause is traced to the phy_device is not disconnected when
removes one r6040 device in r6040_remove_one() or on error handling path
after r6040_mii probed successfully. In r6040_mii_probe(), a net ethernet
device is connected to the first PHY device of mii_bus, in order to
notify the connected driver when the link status changes, which is the
default behavior of the PHY infrastructure to handle everything.
Therefore the phy_device should be disconnected when removes one r6040
device or on error handling path.
Fix it by adding phy_disconnect() when removes one r6040 device or on
error handling path after r6040_mii probed successfully.
In the Linux kernel, the following vulnerability has been resolved:
fs: dlm: fix invalid derefence of sb_lvbptr
I experience issues when putting a lkbsb on the stack and have sb_lvbptr
field to a dangled pointer while not using DLM_LKF_VALBLK. It will crash
with the following kernel message, the dangled pointer is here
0xdeadbeef as example:
[ 102.749317] BUG: unable to handle page fault for address: 00000000deadbeef
[ 102.749320] #PF: supervisor read access in kernel mode
[ 102.749323] #PF: error_code(0x0000) - not-present page
[ 102.749325] PGD 0 P4D 0
[ 102.749332] Oops: 0000 [#1] PREEMPT SMP PTI
[ 102.749336] CPU: 0 PID: 1567 Comm: lock_torture_wr Tainted: G W 5.19.0-rc3+ #1565
[ 102.749343] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.16.0-2.module+el8.7.0+15506+033991b0 04/01/2014
[ 102.749344] RIP: 0010:memcpy_erms+0x6/0x10
[ 102.749353] Code: cc cc cc cc eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 <f3> a4 c3 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe
[ 102.749355] RSP: 0018:ffff97a58145fd08 EFLAGS: 00010202
[ 102.749358] RAX: ffff901778b77070 RBX: 0000000000000000 RCX: 0000000000000040
[ 102.749360] RDX: 0000000000000040 RSI: 00000000deadbeef RDI: ffff901778b77070
[ 102.749362] RBP: ffff97a58145fd10 R08: ffff901760b67a70 R09: 0000000000000001
[ 102.749364] R10: ffff9017008e2cb8 R11: 0000000000000001 R12: ffff901760b67a70
[ 102.749366] R13: ffff901760b78f00 R14: 0000000000000003 R15: 0000000000000001
[ 102.749368] FS: 0000000000000000(0000) GS:ffff901876e00000(0000) knlGS:0000000000000000
[ 102.749372] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 102.749374] CR2: 00000000deadbeef CR3: 000000017c49a004 CR4: 0000000000770ef0
[ 102.749376] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 102.749378] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 102.749379] PKRU: 55555554
[ 102.749381] Call Trace:
[ 102.749382] <TASK>
[ 102.749383] ? send_args+0xb2/0xd0
[ 102.749389] send_common+0xb7/0xd0
[ 102.749395] _unlock_lock+0x2c/0x90
[ 102.749400] unlock_lock.isra.56+0x62/0xa0
[ 102.749405] dlm_unlock+0x21e/0x330
[ 102.749411] ? lock_torture_stats+0x80/0x80 [dlm_locktorture]
[ 102.749416] torture_unlock+0x5a/0x90 [dlm_locktorture]
[ 102.749419] ? preempt_count_sub+0xba/0x100
[ 102.749427] lock_torture_writer+0xbd/0x150 [dlm_locktorture]
[ 102.786186] kthread+0x10a/0x130
[ 102.786581] ? kthread_complete_and_exit+0x20/0x20
[ 102.787156] ret_from_fork+0x22/0x30
[ 102.787588] </TASK>
[ 102.787855] Modules linked in: dlm_locktorture torture rpcsec_gss_krb5 intel_rapl_msr intel_rapl_common kvm_intel iTCO_wdt iTCO_vendor_support kvm vmw_vsock_virtio_transport qxl irqbypass vmw_vsock_virtio_transport_common drm_ttm_helper crc32_pclmul joydev crc32c_intel ttm vsock virtio_scsi virtio_balloon snd_pcm drm_kms_helper virtio_console snd_timer snd drm soundcore syscopyarea i2c_i801 sysfillrect sysimgblt i2c_smbus pcspkr fb_sys_fops lpc_ich serio_raw
[ 102.792536] CR2: 00000000deadbeef
[ 102.792930] ---[ end trace 0000000000000000 ]---
This patch fixes the issue by checking also on DLM_LKF_VALBLK on exflags
is set when copying the lvbptr array instead of if it's just null which
fixes for me the issue.
I think this patch can fix other dlm users as well, depending how they
handle the init, freeing memory handling of sb_lvbptr and don't set
DLM_LKF_VALBLK for some dlm_lock() calls. It might a there could be a
hidden issue all the time. However with checking on DLM_LKF_VALBLK the
user always need to provide a sb_lvbptr non-null value. There might be
more intelligent handling between per ls lvblen, DLM_LKF_VALBLK and
non-null to report the user the way how DLM API is used is wrong but can
be added for later, this will only fix the current behaviour.
In the Linux kernel, the following vulnerability has been resolved:
parisc: Fix locking in pdc_iodc_print() firmware call
Utilize pdc_lock spinlock to protect parallel modifications of the
iodc_dbuf[] buffer, check length to prevent buffer overflow of
iodc_dbuf[], drop the iodc_retbuf[] buffer and fix some wrong
indentings.
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failure
If creation or finalization of a checkpoint fails due to anomalies in the
checkpoint metadata on disk, a kernel warning is generated.
This patch replaces the WARN_ONs by nilfs_error, so that a kernel, booted
with panic_on_warn, does not panic. A nilfs_error is appropriate here to
handle the abnormal filesystem condition.
This also replaces the detected error codes with an I/O error so that
neither of the internal error codes is returned to callers.