iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bpf: Add per-program recursion prevention mechanism

Browse Source 
Since both sleepable and non-sleepable programs execute under migrate_disable
add recursion prevention mechanism to both types of programs when they're
executed via bpf trampoline.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210033634.62081-5-alexei.starovoitov@gmail.com
This commit is contained in:
Alexei Starovoitov
2021-02-09 19:36:29 -08:00
committed by Daniel Borkmann
parent f2dd3b3946
commit ca06f55b90
7 changed files with 50 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
kernel/bpf/core.c
View File

@ -91,6 +91,12 @@ struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flag
vfree(fp);
return NULL;
}
fp->active = alloc_percpu_gfp(int, GFP_KERNEL_ACCOUNT | gfp_extra_flags);
if (!fp->active) {
vfree(fp);
kfree(aux);
return NULL;
}
fp->pages = size / PAGE_SIZE;
fp->aux = aux;
@ -116,6 +122,7 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
prog->stats = alloc_percpu_gfp(struct bpf_prog_stats, gfp_flags);
if (!prog->stats) {
free_percpu(prog->active);
kfree(prog->aux);
vfree(prog);
return NULL;
@ -253,6 +260,7 @@ void __bpf_prog_free(struct bpf_prog *fp)
kfree(fp->aux);
}
free_percpu(fp->stats);
free_percpu(fp->active);
vfree(fp);
}