From: Alexei Starovoitov <[email protected]>
As per the earlier patches, BPF sub-programs have bpf_callback_t
signature and CFI expects callers to have matching signature. This is
violated by bpf_prog_aux::bpf_exception_cb().
[peterz: Changelog]
Reported-by: Peter Zijlstra <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lkml.kernel.org/r/CAADnVQ+Z7UcXXBBhMubhcMM=R-dExk-uHtfOLtoLxQ1XxEpqEA@mail.gmail.com
---
include/linux/bpf.h | 2 +-
kernel/bpf/helpers.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1484,7 +1484,7 @@ struct bpf_prog_aux {
int cgroup_atype; /* enum cgroup_bpf_attach_type */
struct bpf_map *cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE];
char name[BPF_OBJ_NAME_LEN];
- unsigned int (*bpf_exception_cb)(u64 cookie, u64 sp, u64 bp);
+ u64 (*bpf_exception_cb)(u64 cookie, u64 sp, u64 bp, u64, u64);
#ifdef CONFIG_SECURITY
void *security;
#endif
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -2537,7 +2537,7 @@ __bpf_kfunc void bpf_throw(u64 cookie)
* which skips compiler generated instrumentation to do the same.
*/
kasan_unpoison_task_stack_below((void *)(long)ctx.sp);
- ctx.aux->bpf_exception_cb(cookie, ctx.sp, ctx.bp);
+ ctx.aux->bpf_exception_cb(cookie, ctx.sp, ctx.bp, 0, 0);
WARN(1, "A call to BPF exception callback should never return\n");
}