CVE-2023-52580: In the Linux kernel, the following vulnerability has been resolved:net/core: Fix ETH_P_1588 flow dissectorWhen a PTP ethernet raw frame with a size of more than 256 bytes followedby a 0xff pattern is sent to __skb_flow_dissect, nhoff value calculationis wrong. For example: hdr->message_length takes the wrong value (0xffff)and it does not replicate real header length. In this case, 'nhoff' valuewas overridden and the PTP header was badly dissected. This leads to akernel crash.net/core: flow_dissectornet/core flow dissector nhoff = 0x0000000enet/core flow dissector hdr->message_length = 0x0000ffffnet/core flow dissector nhoff = 0x0001000d (u16 overflow)...skb linear:   00000000: 00 a0 c9 00 00 00 00 a0 c9 00 00 00 88skb frag:     00000000: f7 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffUsing the size of the ptp_header struct will allow the correctedcalculation of the nhoff value.net/core flow dissector nhoff = 0x0000000enet/core flow dissector nhoff = 0x00000030 (sizeof ptp_header)...skb linear:   00000000: 00 a0 c9 00 00 00 00 a0 c9 00 00 00 88 f7 ff ffskb linear:   00000010: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffskb linear:   00000020: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffskb frag:     00000000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffKernel trace:[   74.984279] ------------[ cut here ]------------[   74.989471] kernel BUG at include/linux/skbuff.h:2440![   74.995237] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI[   75.001098] CPU: 4 PID: 0 Comm: swapper/4 Tainted: G     U            5.15.85-intel-ese-standard-lts #1[   75.011629] Hardware name: Intel Corporation A-Island (CPU:AlderLake)/A-Island (ID:06), BIOS SB_ADLP.01.01.00.01.03.008.D-6A9D9E73-dirty Mar 30 2023[   75.026507] RIP: 0010:eth_type_trans+0xd0/0x130[   75.031594] Code: 03 88 47 78 eb c7 8b 47 68 2b 47 6c 48 8b 97 c0 00 00 00 83 f8 01 7e 1b 48 85 d2 74 06 66 83 3a ff 74 09 b8 00 04 00 00 eb ab <0f> 0b b8 00 01 00 00 eb a2 48 85 ff 74 eb 48 8d 54 24 06 31 f6 b9[   75.052612] RSP: 0018:ffff9948c0228de0 EFLAGS: 00010297[   75.058473] RAX: 00000000000003f2 RBX: ffff8e47047dc300 RCX: 0000000000001003[   75.066462] RDX: ffff8e4e8c9ea040 RSI: ffff8e4704e0a000 RDI: ffff8e47047dc300[   75.074458] RBP: ffff8e4704e2acc0 R08: 00000000000003f3 R09: 0000000000000800[   75.082466] R10: 000000000000000d R11: ffff9948c0228dec R12: ffff8e4715e4e010[   75.090461] R13: ffff9948c0545018 R14: 0000000000000001 R15: 0000000000000800[   75.098464] FS:  0000000000000000(0000) GS:ffff8e4e8fb00000(0000) knlGS:0000000000000000[   75.107530] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033[   75.113982] CR2: 00007f5eb35934a0 CR3: 0000000150e0a002 CR4: 0000000000770ee0[   75.121980] PKRU: 55555554[   75.125035] Call Trace:[   75.127792]  <IRQ>[   75.130063]  ? eth_get_headlen+0xa4/0xc0[   75.134472]  igc_process_skb_fields+0xcd/0x150[   75.139461]  igc_poll+0xc80/0x17b0[   75.143272]  __napi_poll+0x27/0x170[   75.147192]  net_rx_action+0x234/0x280[   75.151409]  __do_softirq+0xef/0x2f4[   75.155424]  irq_exit_rcu+0xc7/0x110[   75.159432]  common_interrupt+0xb8/0xd0[   75.163748]  </IRQ>[   75.166112]  <TASK>[   75.168473]  asm_common_interrupt+0x22/0x40[   75.173175] RIP: 0010:cpuidle_enter_state+0xe2/0x350[   75.178749] Code: 85 c0 0f 8f 04 02 00 00 31 ff e8 39 6c 67 ff 45 84 ff 74 12 9c 58 f6 c4 02 0f 85 50 02 00 00 31 ff e8 52 b0 6d ff fb 45 85 f6 <0f> 88 b1 00 00 00 49 63 ce 4c 2b 2c 24 48 89 c8 48 6b d1 68 48 c1[   75.199757] RSP: 0018:ffff9948c013bea8 EFLAGS: 00000202[   75.205614] RAX: ffff8e4e8fb00000 RBX: ffffb948bfd23900 RCX: 000000000000001f[   75.213619] RDX: 0000000000000004 RSI: ffffffff94206161 RDI: ffffffff94212e20[   75.221620] RBP: 0000000000000004 R08: 000000117568973a R09: 0000000000000001[   75.229622] R10: 000000000000afc8 R11: ffff8e4e8fb29ce4 R12: ffffffff945ae980[   75.237628] R13: 000000117568973a R14: 0000000000000004 R15: 0000000000000000[   75.245635]  ? ---truncated---
Key phrases: the correctedcalculation of the nhoff value.net/core flow dissector