Fix 32-bit arch and compat support for the kprobe_multi attach type #3026
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Check that size would not overflow before calculation (and return -EOVERFLOW if it will), to prevent potential out-of-bounds write with the following copy_from_user. Use kvmalloc_array in copy_user_syms to prevent out-of-bounds write into syms (and especially buf) as well. Fixes: 0dcac27 ("bpf: Add multi kprobe link") Cc: <stable@vger.kernel.org> # 5.18 Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
It seems that there is no reason not to support 32-bit architectures; doing so requires a bit of rework with respect to cookies handling, however, as the current code implicitly assumes that sizeof(long) == sizeof(u64). Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
For compat processes, userspace size for syms pointers is different. Provide compat handling for copying array elements from the user space. Fixes: 0dcac27 ("bpf: Add multi kprobe link") Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
With the interface as defined, it is impossible to pass 64-bit kernel addresses from a 32-bit userspace process in BPF_LINK_TYPE_KPROBE_MULTI, which severly limits the useability of the interface, change the ABI to accept an array of u64 values instead of (kernel? user?) longs. Interestingly, the rest of the libbpf infrastructure uses 64-bit values for kallsyms addresses already, so this patch also eliminates the sym_addr cast in tools/lib/bpf/libbpf.c:resolve_kprobe_multi_cb(). Fixes: 0dcac27 ("bpf: Add multi kprobe link") Fixes: 5117c26 ("libbpf: Add bpf_link_create support for multi kprobes") Fixes: ddc6b04 ("libbpf: Add bpf_program__attach_kprobe_multi_opts function") Fixes: f7a11ee ("selftests/bpf: Add kprobe_multi attach test") Fixes: 9271a0c ("selftests/bpf: Add attach test for bpf_program__attach_kprobe_multi_opts") Fixes: 2c6401c ("selftests/bpf: Add kprobe_multi bpf_cookie test") Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
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Master branch: 68084a1 |
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At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=642230 expired. Closing PR. |
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Pull request for series with
subject: Fix 32-bit arch and compat support for the kprobe_multi attach type
version: 3
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=642230