CVE-2023-52793 Information

Description

In the Linux kernel the following vulnerability has been resolved:

samples/bpf: syscall_tp_user: Fix array out-of-bound access

Commit 06744f24696e (\samples/bpf: Add openat2() enter/exit tracepoint to syscall_tp sample) added two more eBPF programs to support the openat2() syscall. However it did not increase the size of the array that holds the corresponding bpf_links. This leads to an out-of-bound access on that array in the bpf_object__for_each_program loop and could corrupt other variables on the stack. On our testing QEMU it corrupts the map1_fds array and causes the sample to fail:

./syscall_tp prog 0: map ids 4 5 verify map:4 val: 5 map_lookup failed: Bad file descriptor

Dynamically allocate the array based on the number of programs reported by libbpf to prevent similar inconsistencies in the future

Reference

https://git.kernel.org/stable/c/61576b7a0f28f924da06bead92a39a6d9aa2404a https://git.kernel.org/stable/c/de4825a444560f8cb78b03dda3ba873fab88bc4f https://git.kernel.org/stable/c/9220c3ef6fefbf18f24aeedb1142a642b3de0596