In the Linux kernel, the following vulnerability has been resolved:
netlink: Fix wraparounds of sk->sk_rmem_alloc.
Netlink has this pattern in some places
if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf)
atomic_add(skb->truesize, &sk->sk_rmem_alloc);
, which has the same problem fixed by commit 5a465a0da13e ("udp:
Fix multiple wraparounds of sk->sk_rmem_alloc.").
For example, if we set INT_MAX to SO_RCVBUFFORCE, the condition
is always false as the two operands are of int.
Then, a single socket can eat as many skb as possible until OOM
happens, and we can see multiple wraparounds of sk->sk_rmem_alloc.
Let's fix it by using atomic_add_return() and comparing the two
variables as unsigned int.
Before:
[root@fedora ~]# ss -f netlink
Recv-Q Send-Q Local Address:Port Peer Address:Port
-1668710080 0 rtnl:nl_wraparound/293 *
After:
[root@fedora ~]# ss -f netlink
Recv-Q Send-Q Local Address:Port Peer Address:Port
2147483072 0 rtnl:nl_wraparound/290 *
^
`--- INT_MAX - 576
In the Linux kernel, the following vulnerability has been resolved:
atm: clip: Fix potential null-ptr-deref in to_atmarpd().
atmarpd is protected by RTNL since commit f3a0592b37b8 ("[ATM]: clip
causes unregister hang").
However, it is not enough because to_atmarpd() is called without RTNL,
especially clip_neigh_solicit() / neigh_ops->solicit() is unsleepable.
Also, there is no RTNL dependency around atmarpd.
Let's use a private mutex and RCU to protect access to atmarpd in
to_atmarpd().
In the Linux kernel, the following vulnerability has been resolved:
drm/gem: Acquire references on GEM handles for framebuffers
A GEM handle can be released while the GEM buffer object is attached
to a DRM framebuffer. This leads to the release of the dma-buf backing
the buffer object, if any. [1] Trying to use the framebuffer in further
mode-setting operations leads to a segmentation fault. Most easily
happens with driver that use shadow planes for vmap-ing the dma-buf
during a page flip. An example is shown below.
[ 156.791968] ------------[ cut here ]------------
[ 156.796830] WARNING: CPU: 2 PID: 2255 at drivers/dma-buf/dma-buf.c:1527 dma_buf_vmap+0x224/0x430
[...]
[ 156.942028] RIP: 0010:dma_buf_vmap+0x224/0x430
[ 157.043420] Call Trace:
[ 157.045898] <TASK>
[ 157.048030] ? show_trace_log_lvl+0x1af/0x2c0
[ 157.052436] ? show_trace_log_lvl+0x1af/0x2c0
[ 157.056836] ? show_trace_log_lvl+0x1af/0x2c0
[ 157.061253] ? drm_gem_shmem_vmap+0x74/0x710
[ 157.065567] ? dma_buf_vmap+0x224/0x430
[ 157.069446] ? __warn.cold+0x58/0xe4
[ 157.073061] ? dma_buf_vmap+0x224/0x430
[ 157.077111] ? report_bug+0x1dd/0x390
[ 157.080842] ? handle_bug+0x5e/0xa0
[ 157.084389] ? exc_invalid_op+0x14/0x50
[ 157.088291] ? asm_exc_invalid_op+0x16/0x20
[ 157.092548] ? dma_buf_vmap+0x224/0x430
[ 157.096663] ? dma_resv_get_singleton+0x6d/0x230
[ 157.101341] ? __pfx_dma_buf_vmap+0x10/0x10
[ 157.105588] ? __pfx_dma_resv_get_singleton+0x10/0x10
[ 157.110697] drm_gem_shmem_vmap+0x74/0x710
[ 157.114866] drm_gem_vmap+0xa9/0x1b0
[ 157.118763] drm_gem_vmap_unlocked+0x46/0xa0
[ 157.123086] drm_gem_fb_vmap+0xab/0x300
[ 157.126979] drm_atomic_helper_prepare_planes.part.0+0x487/0xb10
[ 157.133032] ? lockdep_init_map_type+0x19d/0x880
[ 157.137701] drm_atomic_helper_commit+0x13d/0x2e0
[ 157.142671] ? drm_atomic_nonblocking_commit+0xa0/0x180
[ 157.147988] drm_mode_atomic_ioctl+0x766/0xe40
[...]
[ 157.346424] ---[ end trace 0000000000000000 ]---
Acquiring GEM handles for the framebuffer's GEM buffer objects prevents
this from happening. The framebuffer's cleanup later puts the handle
references.
Commit 1a148af06000 ("drm/gem-shmem: Use dma_buf from GEM object
instance") triggers the segmentation fault easily by using the dma-buf
field more widely. The underlying issue with reference counting has
been present before.
v2:
- acquire the handle instead of the BO (Christian)
- fix comment style (Christian)
- drop the Fixes tag (Christian)
- rename err_ gotos
- add missing Link tag
In the Linux kernel, the following vulnerability has been resolved:
i2c: tegra: check msg length in SMBUS block read
For SMBUS block read, do not continue to read if the message length
passed from the device is '0' or greater than the maximum allowed bytes.
In the Linux kernel, the following vulnerability has been resolved:
nfsd: nfsd4_spo_must_allow() must check this is a v4 compound request
If the request being processed is not a v4 compound request, then
examining the cstate can have undefined results.
This patch adds a check that the rpc procedure being executed
(rq_procinfo) is the NFSPROC4_COMPOUND procedure.
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath6kl: remove WARN on bad firmware input
If the firmware gives bad input, that's nothing to do with
the driver's stack at this point etc., so the WARN_ON()
doesn't add any value. Additionally, this is one of the
top syzbot reports now. Just print a message, and as an
added bonus, print the sizes too.
In the Linux kernel, the following vulnerability has been resolved:
mtd: spinand: fix memory leak of ECC engine conf
Memory allocated for the ECC engine conf is not released during spinand
cleanup. Below kmemleak trace is seen for this memory leak:
unreferenced object 0xffffff80064f00e0 (size 8):
comm "swapper/0", pid 1, jiffies 4294937458
hex dump (first 8 bytes):
00 00 00 00 00 00 00 00 ........
backtrace (crc 0):
kmemleak_alloc+0x30/0x40
__kmalloc_cache_noprof+0x208/0x3c0
spinand_ondie_ecc_init_ctx+0x114/0x200
nand_ecc_init_ctx+0x70/0xa8
nanddev_ecc_engine_init+0xec/0x27c
spinand_probe+0xa2c/0x1620
spi_mem_probe+0x130/0x21c
spi_probe+0xf0/0x170
really_probe+0x17c/0x6e8
__driver_probe_device+0x17c/0x21c
driver_probe_device+0x58/0x180
__device_attach_driver+0x15c/0x1f8
bus_for_each_drv+0xec/0x150
__device_attach+0x188/0x24c
device_initial_probe+0x10/0x20
bus_probe_device+0x11c/0x160
Fix the leak by calling nanddev_ecc_engine_cleanup() inside
spinand_cleanup().
In the Linux kernel, the following vulnerability has been resolved:
ACPICA: Refuse to evaluate a method if arguments are missing
As reported in [1], a platform firmware update that increased the number
of method parameters and forgot to update a least one of its callers,
caused ACPICA to crash due to use-after-free.
Since this a result of a clear AML issue that arguably cannot be fixed
up by the interpreter (it cannot produce missing data out of thin air),
address it by making ACPICA refuse to evaluate a method if the caller
attempts to pass fewer arguments than expected to it.