fix(ebpf): hidden_kernel_module fix max iterations #3936
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AlonZivony
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Mar 27, 2024
| @@ -657,6 +657,7 @@ int tracepoint__sched__sched_process_fork(struct bpf_raw_tracepoint_args *ctx) | |||
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| // number of iterations - value that the verifier was seen to cope with - the higher, the better | |||
| #define MAX_NUM_MODULES 450 | |||
| #define MAX_NUM_LOOPS_MODULES 100000 | |||
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Its a bit much, no?
Why not 10k or even less?
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It stops when finishes - so I want a value that if it happens, it'll certainly indicate a problem. 10k is also probably ok but doesn't make much different than 100k.
OriGlassman
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A change was depicted on kernel 6.5 where mod_tree contains duplicate modules and thus MAX_NUM_MODULES is not enough to iterate on the tree, which yielded a warning. The fix is to use bpf_loop helper, which is available on kernels 5.17 and above, and do more iterations.
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1. Explain what the PR does
A change was depicted on kernel 6.5 where mod_tree contains duplicate modules and thus MAX_NUM_MODULES is not enough to iterate on the tree, which yielded a warning.
The fix is to use bpf_loop helper, which is available on kernels 5.17 and above, and do more iterations.
"Replace me with
make check-proutput"2. Explain how to test it
./dist/tracee -e=hidden_kernel_module
3. Other comments