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

bpf, x86: fix freeing of not-finalized bpf_prog_pack

syzbot reported a few issues with bpf_prog_pack [1], [2]. This only happens with multiple subprogs. In jit_subprogs(), we first call bpf_int_jit_compile() on each sub program. And then, we call it on each sub program again. jit_data is not freed in the first call of bpf_int_jit_compile(). Similarly we don't call bpf_jit_binary_pack_finalize() in the first call of bpf_int_jit_compile().

If bpf_int_jit_compile() failed for one sub program, we will call bpf_jit_binary_pack_finalize() for this sub program. However, we don't have a chance to call it for other sub programs. Then we will hit "goto out_free" in jit_subprogs(), and call bpf_jit_free on some subprograms that haven't got bpf_jit_binary_pack_finalize() yet.

At this point, bpf_jit_binary_pack_free() is called and the whole 2MB page is freed erroneously.

Fix this with a custom bpf_jit_free() for x86_64, which calls bpf_jit_binary_pack_finalize() if necessary. Also, with custom bpf_jit_free(), bpf_prog_aux->use_bpf_prog_pack is not needed any more, remove it.

[1] https://syzkaller.appspot.com/bug?extid=2f649ec6d2eea1495a8f [2] https://syzkaller.appspot.com/bug?extid=87f65c75f4a72db05445

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

bpf, x86: fix freeing of not-finalized bpf_prog_pack

syzbot reported a few issues with bpf_prog_pack [1], [2]. This only happens with multiple subprogs. In jit_subprogs(), we first call bpf_int_jit_compile() on each sub program. And then, we call it on each sub program again. jit_data is not freed in the first call of bpf_int_jit_compile(). Similarly we don't call bpf_jit_binary_pack_finalize() in the first call of bpf_int_jit_compile().

If bpf_int_jit_compile() failed for one sub program, we will call bpf_jit_binary_pack_finalize() for this sub program. However, we don't have a chance to call it for other sub programs. Then we will hit "goto out_free" in jit_subprogs(), and call bpf_jit_free on some subprograms that haven't got bpf_jit_binary_pack_finalize() yet.

At this point, bpf_jit_binary_pack_free() is called and the whole 2MB page is freed erroneously.

Fix this with a custom bpf_jit_free() for x86_64, which calls bpf_jit_binary_pack_finalize() if necessary. Also, with custom bpf_jit_free(), bpf_prog_aux->use_bpf_prog_pack is not needed any more, remove it.

[1] https://syzkaller.appspot.com/bug?extid=2f649ec6d2eea1495a8f [2] https://syzkaller.appspot.com/bug?extid=87f65c75f4a72db05445

hw: cpu: AMD CPUs may transiently execute beyond unconditional direct branch kernel: ext4: kernel bug in ext4_write_inline_data_end() kernel: malicious data for FBIOPUT_VSCREENINFO ioctl may cause OOB write memory kernel: hwmon: (mlxreg-fan) Return non-zero value when fan current state is enforced from sysfs kernel: mlxsw: thermal: Fix out-of-bounds memory accesses kernel: mlxsw: spectrum: Protect driver from buggy firmware kernel: net: stmmac: fix tc flower deletion for VLAN priority Rx steering kernel: can: etas_es58x: es58x_rx_err_msg(): fix memory leak in error path kernel: possible race condition in drivers/tty/tty_buffers.c kernel: KVM: NULL pointer dereference in kvm_mmu_invpcid_gva kernel: use-after-free in free_pipe_info() could lead to privilege escalation kernel: KVM: nVMX: missing IBPB when exiting from nested guest can lead to Spectre v2 attacks kernel: netfilter: nf_conntrack_irc message handling issue kernel: race condition in xfrm_probe_algs can lead to OOB read/write kernel: out-of-bounds read in fib_nh_match of the file net/ipv4/fib_semantics.c kernel: race condition in hugetlb_no_page() in mm/hugetlb.c kernel: memory leak in ipv6_renew_options() kernel: data races around icsk->icsk_af_ops in do_ipv6_setsockopt kernel: data races around sk->sk_prot kernel: memory leak in l2cap_recv_acldata of the file net/bluetooth/l2cap_core.c kernel: denial of service in follow_page_pte in mm/gup.c due to poisoned pte entry kernel: use-after-free after failed devlink relo…

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3, Ubuntu:18.04:LTS: linux-gke-4.15, Ubuntu:18.04:LTS: linux-gke-5.4 and 71 more

In the Linux kernel, the following vulnerability has been resolved: bpf, x86: fix freeing of not-finalized bpf_prog_pack syzbot reported a few issues with bpf_prog_pack [1], [2]. This only happens with multiple subprogs. In jit_subprogs(), we first call bpf_int_jit_compile() on each sub program. And then, we call it on each sub program again. jit_data is not freed in the first call of bpf_int_jit_compile(). Similarly we don't call bpf_jit_binary_pack_finalize() in the first call of bpf_int_jit_compile(). If bpf_int_jit_compile() failed for one sub program, we will call bpf_jit_binary_pack_finalize() for this sub program. However, we don't have a chance to call it for other sub programs. Then we will hit "goto out_free" in jit_subprogs(), and call bpf_jit_free on some subprograms that haven't got bpf_jit_binary_pack_finalize() yet. At this point, bpf_jit_binary_pack_free() is called and the whole 2MB page is freed erroneously. Fix this with a custom bpf_jit_free() for x86_64, which calls bpf_jit_binary_pack_finalize() if necessary. Also, with custom bpf_jit_free(), bpf_prog_aux->use_bpf_prog_pack is not needed any more, remove it. [1] https://syzkaller.appspot.com/bug?extid=2f649ec6d2eea1495a8f [2] https://syzkaller.appspot.com/bug?extid=87f65c75f4a72db05445

Ein lokaler Angreifer kann mehrere Schwachstellen in Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen.