cbcvebase.
CVE-2021-47262
published 2024-05-21

CVE-2021-47262: In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Ensure liveliness of nested VM-Enter fail tracepoint message Use the __string()…

PriorityP429high7.1CVSS 3.1
AVLACLPRLUINSUCHINAH
EPSS
0.23%
14.0th percentile
In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Ensure liveliness of nested VM-Enter fail tracepoint message Use the __string() machinery provided by the tracing subystem to make a copy of the string literals consumed by the "nested VM-Enter failed" tracepoint. A complete copy is necessary to ensure that the tracepoint can't outlive the data/memory it consumes and deference stale memory. Because the tracepoint itself is defined by kvm, if kvm-intel and/or kvm-amd are built as modules, the memory holding the string literals defined by the vendor modules will be freed when the module is unloaded, whereas the tracepoint and its data in the ring buffer will live until kvm is unloaded (or "indefinitely" if kvm is built-in). This bug has existed since the tracepoint was added, but was recently exposed by a new check in tracing to detect exactly this type of bug. fmt: '%s%s ' current_buffer: ' vmx_dirty_log_t-140127 [003] .... kvm_nested_vmenter_failed: ' WARNING: CPU: 3 PID: 140134 at kernel/trace/trace.c:3759 trace_check_vprintf+0x3be/0x3e0 CPU: 3 PID: 140134 Comm: less Not tainted 5.13.0-rc1-ce2e73ce600a-req #184 Hardware name: ASUS Q87M-E/Q87M-E, BIOS 1102 03/03/2014 RIP: 0010:trace_check_vprintf+0x3be/0x3e0 Code: 0b 44 8b 4c 24 1c e9 a9 fe ff ff c6 44 02 ff 00 49 8b 97 b0 20 RSP: 0018:ffffa895cc37bcb0 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffffa895cc37bd08 RCX: 0000000000000027 RDX: 0000000000000027 RSI: 00000000ffffdfff RDI: ffff9766cfad74f8 RBP: ffffffffc0a041d4 R08: ffff9766cfad74f0 R09: ffffa895cc37bad8 R10: 0000000000000001 R11: 0000000000000001 R12: ffffffffc0a041d4 R13: ffffffffc0f4dba8 R14: 0000000000000000 R15: ffff976409f2c000 FS: 00007f92fa200740(0000) GS:ffff9766cfac0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000559bd11b0000 CR3: 000000019fbaa002 CR4: 00000000001726e0 Call Trace: trace_event_printf+0x5e/0x80 trace_raw_output_kvm_nested_vmenter_failed+0x3a/0x60 [kvm] print_

Affected

14 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.46-1 (bookworm)linux 5.10.46-1 (bookworm)
linuxlinux
linuxlinux>= 380e0055bc7e4a5c687436ba3ccebb4667836b95 < 796d3bd4ac9316e70c181189318cd2bd98af34bc796d3bd4ac9316e70c181189318cd2bd98af34bc
linuxlinux>= 380e0055bc7e4a5c687436ba3ccebb4667836b95 < d046f724bbd725a24007b7e52b2d675249870888d046f724bbd725a24007b7e52b2d675249870888
linuxlinux>= 380e0055bc7e4a5c687436ba3ccebb4667836b95 < 9fb088ce13bc3c59a51260207b487db3e556f2759fb088ce13bc3c59a51260207b487db3e556f275
linuxlinux>= 380e0055bc7e4a5c687436ba3ccebb4667836b95 < f31500b0d437a2464ca5972d8f5439e156b74960f31500b0d437a2464ca5972d8f5439e156b74960
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 0 < 5.10.46-15.10.46-1
linuxlinux_kernel>= 5.11 < 5.12.115.12.11
linuxlinux_kernel>= 5.4 < 5.4.1265.4.126
linuxlinux_kernel>= 5.5 < 5.10.445.10.44

CVSS provenance

nvdv3.17.1HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
osv7.1HIGH
vendor_debian7.1HIGH
vendor_redhat7.1HIGH
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