tracing: Reject incomplete event filter expressions
A non-empty expression normally finishes in predicate_parse()'s inner
loop, which resolves the pending logical operators before jumping to
finalization. If the input ends after an operator, possibly followed by
unary '!' tokens, the outer loop instead falls through with unresolved
operator state.
For example, "common_pid == 1 || common_pid == 2 &&" leaves
prog[0].target equal to -1. The second pass then reads prog[-1] before
the forward-jump check can reject it. Depending on adjacent slab
contents, it can also copy an out-of-bounds word into a branch target
that passes the forward-only check. A self-targeted perf tracepoint
counting event can reach this path through PERF_EVENT_IOC_SET_FILTER.
Reject the outer-loop fallthrough when a predicate has already been
parsed. This ensures that non-empty expressions only reach finalization
after the inner loop has resolved their operators. Keep the existing
no-filter error for input that has no predicates. Add a regression test
for trailing logical operators and unary negations.
Analysis and contextual insights are available on OpenCVE Cloud.
No solution or workaround provided in the CVE record.
Additional remediation guidance may be available on OpenCVE Cloud.
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Mon, 02 Nov 2026 16:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: tracing: Reject incomplete event filter expressions A non-empty expression normally finishes in predicate_parse()'s inner loop, which resolves the pending logical operators before jumping to finalization. If the input ends after an operator, possibly followed by unary '!' tokens, the outer loop instead falls through with unresolved operator state. For example, "common_pid == 1 || common_pid == 2 &&" leaves prog[0].target equal to -1. The second pass then reads prog[-1] before the forward-jump check can reject it. Depending on adjacent slab contents, it can also copy an out-of-bounds word into a branch target that passes the forward-only check. A self-targeted perf tracepoint counting event can reach this path through PERF_EVENT_IOC_SET_FILTER. Reject the outer-loop fallthrough when a predicate has already been parsed. This ensures that non-empty expressions only reach finalization after the inner loop has resolved their operators. Keep the existing no-filter error for input that has no predicates. Add a regression test for trailing logical operators and unary negations. | |
| Title | tracing: Reject incomplete event filter expressions | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-11-02T16:06:41.950Z
Reserved: 2026-09-25T10:25:14.402Z
Link: CVE-2026-99236
No data.
Status : Received
Published: 2026-11-02T16:17:49.003
Modified: 2026-11-02T16:17:49.003
Link: CVE-2026-99236
No data.
OpenCVE Enrichment
No data.
No weakness.