CVE-2023-53726

*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> arm64: csum: Fix OoB access in IP checksum code for negative lengths<br /> <br /> Although commit c2c24edb1d9c ("arm64: csum: Fix pathological zero-length<br /> calls") added an early return for zero-length input, syzkaller has<br /> popped up with an example of a _negative_ length which causes an<br /> undefined shift and an out-of-bounds read:<br /> <br /> | BUG: KASAN: slab-out-of-bounds in do_csum+0x44/0x254 arch/arm64/lib/csum.c:39<br /> | Read of size 4294966928 at addr ffff0000d7ac0170 by task syz-executor412/5975<br /> |<br /> | CPU: 0 PID: 5975 Comm: syz-executor412 Not tainted 6.4.0-rc4-syzkaller-g908f31f2a05b #0<br /> | Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023<br /> | Call trace:<br /> | dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233<br /> | show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240<br /> | __dump_stack lib/dump_stack.c:88 [inline]<br /> | dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106<br /> | print_address_description mm/kasan/report.c:351 [inline]<br /> | print_report+0x174/0x514 mm/kasan/report.c:462<br /> | kasan_report+0xd4/0x130 mm/kasan/report.c:572<br /> | kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:187<br /> | __kasan_check_read+0x20/0x30 mm/kasan/shadow.c:31<br /> | do_csum+0x44/0x254 arch/arm64/lib/csum.c:39<br /> | csum_partial+0x30/0x58 lib/checksum.c:128<br /> | gso_make_checksum include/linux/skbuff.h:4928 [inline]<br /> | __udp_gso_segment+0xaf4/0x1bc4 net/ipv4/udp_offload.c:332<br /> | udp6_ufo_fragment+0x540/0xca0 net/ipv6/udp_offload.c:47<br /> | ipv6_gso_segment+0x5cc/0x1760 net/ipv6/ip6_offload.c:119<br /> | skb_mac_gso_segment+0x2b4/0x5b0 net/core/gro.c:141<br /> | __skb_gso_segment+0x250/0x3d0 net/core/dev.c:3401<br /> | skb_gso_segment include/linux/netdevice.h:4859 [inline]<br /> | validate_xmit_skb+0x364/0xdbc net/core/dev.c:3659<br /> | validate_xmit_skb_list+0x94/0x130 net/core/dev.c:3709<br /> | sch_direct_xmit+0xe8/0x548 net/sched/sch_generic.c:327<br /> | __dev_xmit_skb net/core/dev.c:3805 [inline]<br /> | __dev_queue_xmit+0x147c/0x3318 net/core/dev.c:4210<br /> | dev_queue_xmit include/linux/netdevice.h:3085 [inline]<br /> | packet_xmit+0x6c/0x318 net/packet/af_packet.c:276<br /> | packet_snd net/packet/af_packet.c:3081 [inline]<br /> | packet_sendmsg+0x376c/0x4c98 net/packet/af_packet.c:3113<br /> | sock_sendmsg_nosec net/socket.c:724 [inline]<br /> | sock_sendmsg net/socket.c:747 [inline]<br /> | __sys_sendto+0x3b4/0x538 net/socket.c:2144<br /> <br /> Extend the early return to reject negative lengths as well, aligning our<br /> implementation with the generic code in lib/checksum.c