diff options
Diffstat (limited to 'include/linux/filter.h')
| -rw-r--r-- | include/linux/filter.h | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h index 0c167fdee5f7..fbf7b39e8103 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -409,6 +409,7 @@ struct bpf_prog { u16 pages; /* Number of allocated pages */ kmemcheck_bitfield_begin(meta); u16 jited:1, /* Is our filter JIT'ed? */ + locked:1, /* Program image locked? */ gpl_compatible:1, /* Is filter GPL compatible? */ cb_access:1, /* Is control block accessed? */ dst_needed:1, /* Do we need dst entry? */ @@ -554,22 +555,29 @@ static inline bool bpf_prog_was_classic(const struct bpf_prog *prog) #ifdef CONFIG_ARCH_HAS_SET_MEMORY static inline void bpf_prog_lock_ro(struct bpf_prog *fp) { - set_memory_ro((unsigned long)fp, fp->pages); + fp->locked = 1; + WARN_ON_ONCE(set_memory_ro((unsigned long)fp, fp->pages)); } static inline void bpf_prog_unlock_ro(struct bpf_prog *fp) { - set_memory_rw((unsigned long)fp, fp->pages); + if (fp->locked) { + WARN_ON_ONCE(set_memory_rw((unsigned long)fp, fp->pages)); + /* In case set_memory_rw() fails, we want to be the first + * to crash here instead of some random place later on. + */ + fp->locked = 0; + } } static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) { - set_memory_ro((unsigned long)hdr, hdr->pages); + WARN_ON_ONCE(set_memory_ro((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); + WARN_ON_ONCE(set_memory_rw((unsigned long)hdr, hdr->pages)); } #else static inline void bpf_prog_lock_ro(struct bpf_prog *fp) |