Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

udmabuf: validate ubuf->pagecount

Syzbot has reported GPF in sg_alloc_append_table_from_pages(). The problem was in ubuf->pages == ZERO_PTR.

ubuf->pagecount is calculated from arguments passed from user-space. If user creates udmabuf with list.size == 0 then ubuf->pagecount will be also equal to zero; it causes kmalloc_array() to return ZERO_PTR.

Fix it by validating ubuf->pagecount before passing it to kmalloc_array().

kernel: off-path attacker may inject data or terminate victim's TCP session kernel: race condition in VT_RESIZEX ioctl when vc_cons[i].d is already NULL leading to NULL pointer dereference kernel: use-after-free vulnerability in function sco_sock_sendmsg() kernel: memory leak for large arguments in video_usercopy function in drivers/media/v4l2-core/v4l2-ioctl.c kernel: mm/damon/dbgfs: protect targets destructions with kdamond_lock kernel: mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() kernel: veth: ensure skb entering GRO are not cloned. kernel: inet: fully convert sk->sk_rx_dst to RCU rules kernel: NFSD: Fix READDIR buffer overflow kernel: cpufreq: CPPC: Fix potential memleak in cppc_cpufreq_cpu_init kernel: nvme-rdma: destroy cm id before destroy qp to avoid use after free kernel: regmap: Fix possible double-free in regcache_rbtree_exit() kernel: ethtool: do not perform operations on net devices being unregistered kernel: scsi: scsi_debug: Fix type in min_t to avoid stack OOB kernel: KVM: x86/mmu: Zap _all_ roots when unmapping gfn range in TDP MMU kernel: udmabuf: validate ubuf->pagecount kernel: drm/virtio: Ensure that objs is not NULL in virtio_gpu_array_put_free() kernel: smb2_ioctl_query_info NULL pointer dereference kernel: NULL pointer dereference in udf_expand_file_adinicbdue() during writeback kernel: swiotlb information leak with DMA_FROM_DEVICE kernel: uninitialized registers on stack in nft_do_chain can cause kernel pointer leakage to UM k…