CVE-2024-49850: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: bpf: correctly handle malformed BPF_CORE_TYPE_ID_LOCAL relos In case of malformed relocation record of kind BPF_CORE_TYPE_ID_LOCAL referencing a non-existing BTF type, function bpf_core_calc_relo_insn would cause a null pointer deference. Fix this by adding a proper check upper in call stack, as malformed relocation records could be passed from user space. Simplest reproducer is a program: r0 = 0 exit With a single relocation record: .insn_off = 0, /* patch first instruction */ .type_id = 100500, /* this type id does not exist */ .access_str_off = 6, /* offset of string "0" */ .kind = BPF_CORE_TYPE_ID_LOCAL, See the link for original reproducer or next commit for a test case.
CVE-2024-49850CVSS 5.5Linux

CVE-2024-49850: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: bpf: correctly handle malformed BPF_CORE_TYPE_ID_LOCAL relos In case of malformed relocation record of kind BPF_CORE_TYPE_ID_LOCAL referencing a non-existing BTF type, function bpf_core_calc_relo_insn would cause a null pointer deference. Fix this by adding a proper check upper in call stack, as malformed relocation records could be passed from user space. Simplest reproducer is a program: r0 = 0 exit With a single relocation record: .insn_off = 0, /* patch first instruction */ .type_id = 100500, /* this type id does not exist */ .access_str_off = 6, /* offset of string "0" */ .kind = BPF_CORE_TYPE_ID_LOCAL, See the link for original reproducer or next commit for a test case.

CVSS
5.5 MEDIUM
EPSS
10.8%
Known exploited
not in KEV
Product
linux kernel

What is known

In the Linux kernel, the following vulnerability has been resolved: bpf: correctly handle malformed BPF_CORE_TYPE_ID_LOCAL relos In case of malformed relocation record of kind BPF_CORE_TYPE_ID_LOCAL referencing a non-existing BTF type, function bpf_core_calc_relo_insn would cause a null pointer deference. Fix this by adding a proper check upper in call stack, as malformed relocation records could be passed from user space. Simplest reproducer is a program: r0 = 0 exit With a single relocation record: .insn_off = 0, /* patch first instruction */ .type_id = 100500, /* this type id does not exist */ .access_str_off = 6, /* offset of string "0" */ .kind = BPF_CORE_TYPE_ID_LOCAL, See the link for original reproducer or next commit for a test case.

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