The VFIO PCI driver in the Linux kernel through 5.6.13 mishandles attempts to access disabled memory space.

A signal access-control issue was discovered in the Linux kernel before 5.6.5, aka CID-7395ea4e65c2. Because exec_id in include/linux/sched.h is only 32 bits, an integer overflow can interfere with a do_notify_parent protection mechanism. A child process can send an arbitrary signal to a parent process in a different security domain. Exploitation limitations include the amount of elapsed time before an integer overflow occurs, and the lack of scenarios where signals to a parent process present a substantial operational threat.

An issue was discovered in the Linux kernel through 5.6.11. btree_gc_coalesce in drivers/md/bcache/btree.c has a deadlock if a coalescing operation fails.

An issue was discovered in the Linux kernel through 5.6.11. sg_write lacks an sg_remove_request call in a certain failure case, aka CID-83c6f2390040.

An issue was discovered in the Linux kernel before 5.6. svm_cpu_uninit in arch/x86/kvm/svm.c has a memory leak, aka CID-d80b64ff297e. NOTE: third parties dispute this issue because it's a one-time leak at the boot, the size is negligible, and it can't be triggered at will

An issue was discovered in the Linux kernel 4.18 through 5.6.11 when unprivileged user namespaces are allowed. A user can create their own PID namespace, and mount a FUSE filesystem. Upon interaction with this FUSE filesystem, if the userspace component is terminated via a kill of the PID namespace's pid 1, it will result in a hung task, and resources being permanently locked up until system reboot. This can result in resource exhaustion.

An issue was discovered in the Linux kernel before 5.6.7. xdp_umem_reg in net/xdp/xdp_umem.c has an out-of-bounds write (by a user with the CAP_NET_ADMIN capability) because of a lack of headroom validation.

An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.

gss_mech_free in net/sunrpc/auth_gss/gss_mech_switch.c in the rpcsec_gss_krb5 implementation in the Linux kernel through 5.6.10 lacks certain domain_release calls, leading to a memory leak. Note: This was disputed with the assertion that the issue does not grant any access not already available. It is a problem that on unloading a specific kernel module some memory is leaked, but loading kernel modules is a privileged operation. A user could also write a kernel module to consume any amount of memory they like and load that replicating the effect of this bug

An issue was discovered in xfs_agf_verify in fs/xfs/libxfs/xfs_alloc.c in the Linux kernel through 5.6.10. Attackers may trigger a sync of excessive duration via an XFS v5 image with crafted metadata, aka CID-d0c7feaf8767.

An array overflow was discovered in mt76_add_fragment in drivers/net/wireless/mediatek/mt76/dma.c in the Linux kernel before 5.5.10, aka CID-b102f0c522cf. An oversized packet with too many rx fragments can corrupt memory of adjacent pages.

usb_sg_cancel in drivers/usb/core/message.c in the Linux kernel before 5.6.8 has a use-after-free because a transfer occurs without a reference, aka CID-056ad39ee925.

In the Linux kernel 4.19 through 5.6.7 on the s390 platform, code execution may occur because of a race condition, as demonstrated by code in enable_sacf_uaccess in arch/s390/lib/uaccess.c that fails to protect against a concurrent page table upgrade, aka CID-3f777e19d171. A crash could also occur.

snd_ctl_elem_add in sound/core/control.c in the Linux kernel through 5.6.3 has a count=info->owner line, which later affects a private_size*count multiplication for unspecified "interesting side effects." NOTE: kernel engineers dispute this finding, because it could be relevant only if new callers were added that were unfamiliar with the misuse of the info->owner field to represent data unrelated to the "owner" concept. The existing callers, SNDRV_CTL_IOCTL_ELEM_ADD and SNDRV_CTL_IOCTL_ELEM_REPLACE, have been designed to misuse the info->owner field in a safe way

In the Linux kernel before 5.6.1, drivers/media/usb/gspca/xirlink_cit.c (aka the Xirlink camera USB driver) mishandles invalid descriptors, aka CID-a246b4d54770.

An issue was discovered in the stv06xx subsystem in the Linux kernel before 5.6.1. drivers/media/usb/gspca/stv06xx/stv06xx.c and drivers/media/usb/gspca/stv06xx/stv06xx_pb0100.c mishandle invalid descriptors, as demonstrated by a NULL pointer dereference, aka CID-485b06aadb93.

An issue was discovered in the Linux kernel before 5.6.1. drivers/media/usb/gspca/ov519.c allows NULL pointer dereferences in ov511_mode_init_regs and ov518_mode_init_regs when there are zero endpoints, aka CID-998912346c0d.

An issue was discovered in the Linux kernel through 5.6.2. mpol_parse_str in mm/mempolicy.c has a stack-based out-of-bounds write because an empty nodelist is mishandled during mount option parsing, aka CID-aa9f7d5172fa. NOTE: Someone in the security community disagrees that this is a vulnerability because the issue “is a bug in parsing mount options which can only be specified by a privileged user, so triggering the bug does not grant any powers not already held.”

An issue was discovered in slc_bump in drivers/net/can/slcan.c in the Linux kernel 3.16 through 5.6.2. It allows attackers to read uninitialized can_frame data, potentially containing sensitive information from kernel stack memory, if the configuration lacks CONFIG_INIT_STACK_ALL, aka CID-b9258a2cece4.

In the Linux kernel 5.5.0 and newer, the bpf verifier (kernel/bpf/verifier.c) did not properly restrict the register bounds for 32-bit operations, leading to out-of-bounds reads and writes in kernel memory. The vulnerability also affects the Linux 5.4 stable series, starting with v5.4.7, as the introducing commit was backported to that branch. This vulnerability was fixed in 5.6.1, 5.5.14, and 5.4.29. (issue is aka ZDI-CAN-10780)