{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-49892","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-05-01T14:05:17.243Z","datePublished":"2025-05-01T14:10:35.815Z","dateUpdated":"2026-05-11T19:08:45.684Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-11T19:08:45.684Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nftrace: Fix use-after-free for dynamic ftrace_ops\n\nKASAN reported a use-after-free with ftrace ops [1]. It was found from\nvmcore that perf had registered two ops with the same content\nsuccessively, both dynamic. After unregistering the second ops, a\nuse-after-free occurred.\n\nIn ftrace_shutdown(), when the second ops is unregistered, the\nFTRACE_UPDATE_CALLS command is not set because there is another enabled\nops with the same content.  Also, both ops are dynamic and the ftrace\ncallback function is ftrace_ops_list_func, so the\nFTRACE_UPDATE_TRACE_FUNC command will not be set. Eventually the value\nof 'command' will be 0 and ftrace_shutdown() will skip the rcu\nsynchronization.\n\nHowever, ftrace may be activated. When the ops is released, another CPU\nmay be accessing the ops.  Add the missing synchronization to fix this\nproblem.\n\n[1]\nBUG: KASAN: use-after-free in __ftrace_ops_list_func kernel/trace/ftrace.c:7020 [inline]\nBUG: KASAN: use-after-free in ftrace_ops_list_func+0x2b0/0x31c kernel/trace/ftrace.c:7049\nRead of size 8 at addr ffff56551965bbc8 by task syz-executor.2/14468\n\nCPU: 1 PID: 14468 Comm: syz-executor.2 Not tainted 5.10.0 #7\nHardware name: linux,dummy-virt (DT)\nCall trace:\n dump_backtrace+0x0/0x40c arch/arm64/kernel/stacktrace.c:132\n show_stack+0x30/0x40 arch/arm64/kernel/stacktrace.c:196\n __dump_stack lib/dump_stack.c:77 [inline]\n dump_stack+0x1b4/0x248 lib/dump_stack.c:118\n print_address_description.constprop.0+0x28/0x48c mm/kasan/report.c:387\n __kasan_report mm/kasan/report.c:547 [inline]\n kasan_report+0x118/0x210 mm/kasan/report.c:564\n check_memory_region_inline mm/kasan/generic.c:187 [inline]\n __asan_load8+0x98/0xc0 mm/kasan/generic.c:253\n __ftrace_ops_list_func kernel/trace/ftrace.c:7020 [inline]\n ftrace_ops_list_func+0x2b0/0x31c kernel/trace/ftrace.c:7049\n ftrace_graph_call+0x0/0x4\n __might_sleep+0x8/0x100 include/linux/perf_event.h:1170\n __might_fault mm/memory.c:5183 [inline]\n __might_fault+0x58/0x70 mm/memory.c:5171\n do_strncpy_from_user lib/strncpy_from_user.c:41 [inline]\n strncpy_from_user+0x1f4/0x4b0 lib/strncpy_from_user.c:139\n getname_flags+0xb0/0x31c fs/namei.c:149\n getname+0x2c/0x40 fs/namei.c:209\n [...]\n\nAllocated by task 14445:\n kasan_save_stack+0x24/0x50 mm/kasan/common.c:48\n kasan_set_track mm/kasan/common.c:56 [inline]\n __kasan_kmalloc mm/kasan/common.c:479 [inline]\n __kasan_kmalloc.constprop.0+0x110/0x13c mm/kasan/common.c:449\n kasan_kmalloc+0xc/0x14 mm/kasan/common.c:493\n kmem_cache_alloc_trace+0x440/0x924 mm/slub.c:2950\n kmalloc include/linux/slab.h:563 [inline]\n kzalloc include/linux/slab.h:675 [inline]\n perf_event_alloc.part.0+0xb4/0x1350 kernel/events/core.c:11230\n perf_event_alloc kernel/events/core.c:11733 [inline]\n __do_sys_perf_event_open kernel/events/core.c:11831 [inline]\n __se_sys_perf_event_open+0x550/0x15f4 kernel/events/core.c:11723\n __arm64_sys_perf_event_open+0x6c/0x80 kernel/events/core.c:11723\n [...]\n\nFreed by task 14445:\n kasan_save_stack+0x24/0x50 mm/kasan/common.c:48\n kasan_set_track+0x24/0x34 mm/kasan/common.c:56\n kasan_set_free_info+0x20/0x40 mm/kasan/generic.c:358\n __kasan_slab_free.part.0+0x11c/0x1b0 mm/kasan/common.c:437\n __kasan_slab_free mm/kasan/common.c:445 [inline]\n kasan_slab_free+0x2c/0x40 mm/kasan/common.c:446\n slab_free_hook mm/slub.c:1569 [inline]\n slab_free_freelist_hook mm/slub.c:1608 [inline]\n slab_free mm/slub.c:3179 [inline]\n kfree+0x12c/0xc10 mm/slub.c:4176\n perf_event_alloc.part.0+0xa0c/0x1350 kernel/events/core.c:11434\n perf_event_alloc kernel/events/core.c:11733 [inline]\n __do_sys_perf_event_open kernel/events/core.c:11831 [inline]\n __se_sys_perf_event_open+0x550/0x15f4 kernel/events/core.c:11723\n [...]"}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/ftrace.c"],"versions":[{"version":"edb096e00724f02db5f6ec7900f3bbd465c6c76f","lessThan":"ea5f2fd4640ecbb9df969bf8bb27733ae2183169","status":"affected","versionType":"git"},{"version":"edb096e00724f02db5f6ec7900f3bbd465c6c76f","lessThan":"88561a66777e7a2fe06638c6dcb22a9fae0b6733","status":"affected","versionType":"git"},{"version":"edb096e00724f02db5f6ec7900f3bbd465c6c76f","lessThan":"cc1b9961a0ceb70f6ca4e2f4b8bb71c87c7a495c","status":"affected","versionType":"git"},{"version":"edb096e00724f02db5f6ec7900f3bbd465c6c76f","lessThan":"0e792b89e6800cd9cb4757a76a96f7ef3e8b6294","status":"affected","versionType":"git"},{"version":"a60e407b961e818541ff7924afa8e51fbdb21a61","status":"affected","versionType":"git"},{"version":"ed1bf4397d2219d4b9ec2d5517416ba102186650","status":"affected","versionType":"git"},{"version":"100553e197e2c41eccf9fa04b2be9cd11ae21215","status":"affected","versionType":"git"},{"version":"30d3c1c9c9dd31b3c3a5aa0f4f40f1e321c6c791","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/trace/ftrace.c"],"versions":[{"version":"4.14","status":"affected"},{"version":"0","lessThan":"4.14","status":"unaffected","versionType":"semver"},{"version":"5.10.154","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.78","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.0.8","lessThanOrEqual":"6.0.*","status":"unaffected","versionType":"semver"},{"version":"6.1","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"5.10.154"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"5.15.78"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.0.8"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.14","versionEndExcluding":"6.1"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.1.45"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.4.89"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.9.52"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.13.4"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/ea5f2fd4640ecbb9df969bf8bb27733ae2183169"},{"url":"https://git.kernel.org/stable/c/88561a66777e7a2fe06638c6dcb22a9fae0b6733"},{"url":"https://git.kernel.org/stable/c/cc1b9961a0ceb70f6ca4e2f4b8bb71c87c7a495c"},{"url":"https://git.kernel.org/stable/c/0e792b89e6800cd9cb4757a76a96f7ef3e8b6294"}],"title":"ftrace: Fix use-after-free for dynamic ftrace_ops","x_generator":{"engine":"bippy-1.2.0"}}}}