Use new flag VM_HAS_SPECIAL_PERMS for handling freeing of special permissioned memory in vmalloc and remove places where memory was set RW before freeing which is no longer needed. Also we no longer need a bit to track if the memory is RO because it is tracked in vmalloc.
Cc: Daniel Borkmann <[email protected]> Cc: Alexei Starovoitov <[email protected]> Signed-off-by: Rick Edgecombe <[email protected]> --- include/linux/filter.h | 16 +++------------- kernel/bpf/core.c | 1 - 2 files changed, 3 insertions(+), 14 deletions(-) diff --git a/include/linux/filter.h b/include/linux/filter.h index 9cdfab7f383c..cc9581dd9c58 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -20,6 +20,7 @@ #include <linux/set_memory.h> #include <linux/kallsyms.h> #include <linux/if_vlan.h> +#include <linux/vmalloc.h> #include <net/sch_generic.h> @@ -483,7 +484,6 @@ struct bpf_prog { u16 pages; /* Number of allocated pages */ u16 jited:1, /* Is our filter JIT'ed? */ jit_requested:1,/* archs need to JIT the prog */ - undo_set_mem:1, /* Passed set_memory_ro() checkpoint */ gpl_compatible:1, /* Is filter GPL compatible? */ cb_access:1, /* Is control block accessed? */ dst_needed:1, /* Do we need dst entry? */ @@ -681,26 +681,17 @@ bpf_ctx_narrow_access_ok(u32 off, u32 size, u32 size_default) static inline void bpf_prog_lock_ro(struct bpf_prog *fp) { + set_vm_special(fp); set_memory_ro((unsigned long)fp, fp->pages); } -static inline void bpf_prog_unlock_ro(struct bpf_prog *fp) -{ - if (fp->undo_set_mem) - set_memory_rw((unsigned long)fp, fp->pages); -} - static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) { + set_vm_special(hdr); set_memory_ro((unsigned long)hdr, hdr->pages); set_memory_x((unsigned long)hdr, hdr->pages); } -static inline void bpf_jit_binary_unlock_ro(struct bpf_binary_header *hdr) -{ - set_memory_rw((unsigned long)hdr, hdr->pages); -} - static inline struct bpf_binary_header * bpf_jit_binary_hdr(const struct bpf_prog *fp) { @@ -735,7 +726,6 @@ void __bpf_prog_free(struct bpf_prog *fp); static inline void bpf_prog_unlock_free(struct bpf_prog *fp) { - bpf_prog_unlock_ro(fp); __bpf_prog_free(fp); } diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 19c49313c709..465c1c3623e8 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -804,7 +804,6 @@ void __weak bpf_jit_free(struct bpf_prog *fp) if (fp->jited) { struct bpf_binary_header *hdr = bpf_jit_binary_hdr(fp); - bpf_jit_binary_unlock_ro(hdr); bpf_jit_binary_free(hdr); WARN_ON_ONCE(!bpf_prog_kallsyms_verify_off(fp)); -- 2.17.1
