{ "data_version": "4.0", "data_type": "CVE", "data_format": "MITRE", "CVE_data_meta": { "ID": "CVE-2024-26865", "ASSIGNER": "cve@kernel.org", "STATE": "PUBLIC" }, "description": { "description_data": [ { "lang": "eng", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrds: tcp: Fix use-after-free of net in reqsk_timer_handler().\n\nsyzkaller reported a warning of netns tracker [0] followed by KASAN\nsplat [1] and another ref tracker warning [1].\n\nsyzkaller could not find a repro, but in the log, the only suspicious\nsequence was as follows:\n\n 18:26:22 executing program 1:\n r0 = socket$inet6_mptcp(0xa, 0x1, 0x106)\n ...\n connect$inet6(r0, &(0x7f0000000080)={0xa, 0x4001, 0x0, @loopback}, 0x1c) (async)\n\nThe notable thing here is 0x4001 in connect(), which is RDS_TCP_PORT.\n\nSo, the scenario would be:\n\n 1. unshare(CLONE_NEWNET) creates a per netns tcp listener in\n rds_tcp_listen_init().\n 2. syz-executor connect()s to it and creates a reqsk.\n 3. syz-executor exit()s immediately.\n 4. netns is dismantled. [0]\n 5. reqsk timer is fired, and UAF happens while freeing reqsk. [1]\n 6. listener is freed after RCU grace period. [2]\n\nBasically, reqsk assumes that the listener guarantees netns safety\nuntil all reqsk timers are expired by holding the listener's refcount.\nHowever, this was not the case for kernel sockets.\n\nCommit 740ea3c4a0b2 (\"tcp: Clean up kernel listener's reqsk in\ninet_twsk_purge()\") fixed this issue only for per-netns ehash.\n\nLet's apply the same fix for the global ehash.\n\n[0]:\nref_tracker: net notrefcnt@0000000065449cc3 has 1/1 users at\n sk_alloc (./include/net/net_namespace.h:337 net/core/sock.c:2146)\n inet6_create (net/ipv6/af_inet6.c:192 net/ipv6/af_inet6.c:119)\n __sock_create (net/socket.c:1572)\n rds_tcp_listen_init (net/rds/tcp_listen.c:279)\n rds_tcp_init_net (net/rds/tcp.c:577)\n ops_init (net/core/net_namespace.c:137)\n setup_net (net/core/net_namespace.c:340)\n copy_net_ns (net/core/net_namespace.c:497)\n create_new_namespaces (kernel/nsproxy.c:110)\n unshare_nsproxy_namespaces (kernel/nsproxy.c:228 (discriminator 4))\n ksys_unshare (kernel/fork.c:3429)\n __x64_sys_unshare (kernel/fork.c:3496)\n do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129)\n...\nWARNING: CPU: 0 PID: 27 at lib/ref_tracker.c:179 ref_tracker_dir_exit (lib/ref_tracker.c:179)\n\n[1]:\nBUG: KASAN: slab-use-after-free in inet_csk_reqsk_queue_drop (./include/net/inet_hashtables.h:180 net/ipv4/inet_connection_sock.c:952 net/ipv4/inet_connection_sock.c:966)\nRead of size 8 at addr ffff88801b370400 by task swapper/0/0\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014\nCall Trace:\n \n dump_stack_lvl (lib/dump_stack.c:107 (discriminator 1))\n print_report (mm/kasan/report.c:378 mm/kasan/report.c:488)\n kasan_report (mm/kasan/report.c:603)\n inet_csk_reqsk_queue_drop (./include/net/inet_hashtables.h:180 net/ipv4/inet_connection_sock.c:952 net/ipv4/inet_connection_sock.c:966)\n reqsk_timer_handler (net/ipv4/inet_connection_sock.c:979 net/ipv4/inet_connection_sock.c:1092)\n call_timer_fn (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/timer.h:127 kernel/time/timer.c:1701)\n __run_timers.part.0 (kernel/time/timer.c:1752 kernel/time/timer.c:2038)\n run_timer_softirq (kernel/time/timer.c:2053)\n __do_softirq (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/irq.h:142 kernel/softirq.c:554)\n irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632 kernel/softirq.c:644)\n sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1076 (discriminator 14))\n \n\nAllocated by task 258 on cpu 0 at 83.612050s:\n kasan_save_stack (mm/kasan/common.c:48)\n kasan_save_track (mm/kasan/common.c:68)\n __kasan_slab_alloc (mm/kasan/common.c:343)\n kmem_cache_alloc (mm/slub.c:3813 mm/slub.c:3860 mm/slub.c:3867)\n copy_net_ns (./include/linux/slab.h:701 net/core/net_namespace.c:421 net/core/net_namespace.c:480)\n create_new_namespaces (kernel/nsproxy.c:110)\n unshare_nsproxy_name\n---truncated---" } ] }, "problemtype": { "problemtype_data": [ { "description": [ { "lang": "eng", "value": "n/a" } ] } ] }, "affects": { "vendor": { "vendor_data": [ { "vendor_name": "Linux", "product": { "product_data": [ { "product_name": "Linux", "version": { "version_data": [ { "version_affected": "<", "version_name": "467fa15356ac", "version_value": "9905a157048f" }, { "version_value": "not down converted", "x_cve_json_5_version_data": { "versions": [ { "version": "4.3", "status": "affected" }, { "version": "0", "lessThan": "4.3", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.83", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.23", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.7.11", "lessThanOrEqual": "6.7.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.8.2", "lessThanOrEqual": "6.8.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.9", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ], "defaultStatus": "affected" } } ] } } ] } } ] } }, "references": { "reference_data": [ { "url": "https://git.kernel.org/stable/c/9905a157048f441f1412e7bd13372f4a971d75c6", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/9905a157048f441f1412e7bd13372f4a971d75c6" }, { "url": "https://git.kernel.org/stable/c/f901ee07853ce97e9f1104c7c898fbbe447f0279", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/f901ee07853ce97e9f1104c7c898fbbe447f0279" }, { "url": "https://git.kernel.org/stable/c/9ceac040506a05a30b104b2aa2e9146810704500", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/9ceac040506a05a30b104b2aa2e9146810704500" }, { "url": "https://git.kernel.org/stable/c/1e9fd5cf8d7f487332560f7bb312fc7d416817f3", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/1e9fd5cf8d7f487332560f7bb312fc7d416817f3" }, { "url": "https://git.kernel.org/stable/c/2a750d6a5b365265dbda33330a6188547ddb5c24", "refsource": "MISC", "name": "https://git.kernel.org/stable/c/2a750d6a5b365265dbda33330a6188547ddb5c24" } ] }, "generator": { "engine": "bippy-9e1c9544281a" } }