Le 01/03/2024 à 08:57, Christophe Leroy a écrit : > set_memory_rox() can fail, leaving memory unprotected. > > Check return and bail out when bpf_jit_binary_lock_ro() returns > an error. > Definitely not a good day for me. I switched maintainers between patch 1 and patch 2 sorry. Adding hengqi.chen@xxxxxxxxx, svens@xxxxxxxxxxxxx, dsahern@xxxxxxxxxx, mingo@xxxxxxxxxx, James.Bottomley@xxxxxxxxxxxxxxxxxxxxx, tsbogend@xxxxxxxxxxxxxxxx, x86@xxxxxxxxxx, tglx@xxxxxxxxxxxxx, paulburton@xxxxxxxxxx, hca@xxxxxxxxxxxxx, udknight@xxxxxxxxx, bp@xxxxxxxxx, chenhuacai@xxxxxxxxxx, hpa@xxxxxxxxx, gor@xxxxxxxxxxxxx, linux@xxxxxxxxxxxxxxx, kernel@xxxxxxxxxx, dave.hansen@xxxxxxxxxxxxxxx, borntraeger@xxxxxxxxxxxxx, agordeev@xxxxxxxxxxxxx, deller@xxxxxx Tell me if I need to resend the series once more. Thanks Christophe > Link: https://github.com/KSPP/linux/issues/7 > Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> > Cc: linux-hardening@xxxxxxxxxxxxxxx <linux-hardening@xxxxxxxxxxxxxxx> > Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> > Reviewed-by: Puranjay Mohan <puranjay12@xxxxxxxxx> > Reviewed-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx> # s390x > Acked-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> # LoongArch > Reviewed-by: Johan Almbladh <johan.almbladh@xxxxxxxxxxxxxxxxx> # MIPS Part > --- > Sorry for the resend, I forgot to flag patch 2 as bpf-next > > Previous patch introduces a dependency on this patch because it modifies bpf_prog_lock_ro(), but they are independant. > It is possible to apply this patch as standalone by handling trivial conflict with unmodified bpf_prog_lock_ro(). > > v2: > - Dropped arm64 change following commit 1dad391daef1 ("bpf, arm64: use bpf_prog_pack for memory management") > - Fixed too long lines reported by checkpatch > --- > arch/arm/net/bpf_jit_32.c | 25 ++++++++++++------------- > arch/loongarch/net/bpf_jit.c | 22 ++++++++++++++++------ > arch/mips/net/bpf_jit_comp.c | 3 ++- > arch/parisc/net/bpf_jit_core.c | 8 +++++++- > arch/s390/net/bpf_jit_comp.c | 6 +++++- > arch/sparc/net/bpf_jit_comp_64.c | 6 +++++- > arch/x86/net/bpf_jit_comp32.c | 3 +-- > include/linux/filter.h | 5 +++-- > 8 files changed, 51 insertions(+), 27 deletions(-) > > diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c > index 1d672457d02f..01516f83a95a 100644 > --- a/arch/arm/net/bpf_jit_32.c > +++ b/arch/arm/net/bpf_jit_32.c > @@ -2222,28 +2222,21 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > /* If building the body of the JITed code fails somehow, > * we fall back to the interpretation. > */ > - if (build_body(&ctx) < 0) { > - image_ptr = NULL; > - bpf_jit_binary_free(header); > - prog = orig_prog; > - goto out_imms; > - } > + if (build_body(&ctx) < 0) > + goto out_free; > build_epilogue(&ctx); > > /* 3.) Extra pass to validate JITed Code */ > - if (validate_code(&ctx)) { > - image_ptr = NULL; > - bpf_jit_binary_free(header); > - prog = orig_prog; > - goto out_imms; > - } > + if (validate_code(&ctx)) > + goto out_free; > flush_icache_range((u32)header, (u32)(ctx.target + ctx.idx)); > > if (bpf_jit_enable > 1) > /* there are 2 passes here */ > bpf_jit_dump(prog->len, image_size, 2, ctx.target); > > - bpf_jit_binary_lock_ro(header); > + if (bpf_jit_binary_lock_ro(header)) > + goto out_free; > prog->bpf_func = (void *)ctx.target; > prog->jited = 1; > prog->jited_len = image_size; > @@ -2260,5 +2253,11 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > bpf_jit_prog_release_other(prog, prog == orig_prog ? > tmp : orig_prog); > return prog; > + > +out_free: > + image_ptr = NULL; > + bpf_jit_binary_free(header); > + prog = orig_prog; > + goto out_imms; > } > > diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c > index e73323d759d0..7dbefd4ba210 100644 > --- a/arch/loongarch/net/bpf_jit.c > +++ b/arch/loongarch/net/bpf_jit.c > @@ -1294,16 +1294,19 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > flush_icache_range((unsigned long)header, (unsigned long)(ctx.image + ctx.idx)); > > if (!prog->is_func || extra_pass) { > + int err; > + > if (extra_pass && ctx.idx != jit_data->ctx.idx) { > pr_err_once("multi-func JIT bug %d != %d\n", > ctx.idx, jit_data->ctx.idx); > - bpf_jit_binary_free(header); > - prog->bpf_func = NULL; > - prog->jited = 0; > - prog->jited_len = 0; > - goto out_offset; > + goto out_free; > + } > + err = bpf_jit_binary_lock_ro(header); > + if (err) { > + pr_err_once("bpf_jit_binary_lock_ro() returned %d\n", > + err); > + goto out_free; > } > - bpf_jit_binary_lock_ro(header); > } else { > jit_data->ctx = ctx; > jit_data->image = image_ptr; > @@ -1334,6 +1337,13 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > out_offset = -1; > > return prog; > + > +out_free: > + bpf_jit_binary_free(header); > + prog->bpf_func = NULL; > + prog->jited = 0; > + prog->jited_len = 0; > + goto out_offset; > } > > /* Indicate the JIT backend supports mixing bpf2bpf and tailcalls. */ > diff --git a/arch/mips/net/bpf_jit_comp.c b/arch/mips/net/bpf_jit_comp.c > index a40d926b6513..e355dfca4400 100644 > --- a/arch/mips/net/bpf_jit_comp.c > +++ b/arch/mips/net/bpf_jit_comp.c > @@ -1012,7 +1012,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > bpf_prog_fill_jited_linfo(prog, &ctx.descriptors[1]); > > /* Set as read-only exec and flush instruction cache */ > - bpf_jit_binary_lock_ro(header); > + if (bpf_jit_binary_lock_ro(header)) > + goto out_err; > flush_icache_range((unsigned long)header, > (unsigned long)&ctx.target[ctx.jit_index]); > > diff --git a/arch/parisc/net/bpf_jit_core.c b/arch/parisc/net/bpf_jit_core.c > index d6ee2fd45550..979f45d4d1fb 100644 > --- a/arch/parisc/net/bpf_jit_core.c > +++ b/arch/parisc/net/bpf_jit_core.c > @@ -167,7 +167,13 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > bpf_flush_icache(jit_data->header, ctx->insns + ctx->ninsns); > > if (!prog->is_func || extra_pass) { > - bpf_jit_binary_lock_ro(jit_data->header); > + if (bpf_jit_binary_lock_ro(jit_data->header)) { > + bpf_jit_binary_free(jit_data->header); > + prog->bpf_func = NULL; > + prog->jited = 0; > + prog->jited_len = 0; > + goto out_offset; > + } > prologue_len = ctx->epilogue_offset - ctx->body_len; > for (i = 0; i < prog->len; i++) > ctx->offset[i] += prologue_len; > diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c > index b418333bb086..e613eebfd349 100644 > --- a/arch/s390/net/bpf_jit_comp.c > +++ b/arch/s390/net/bpf_jit_comp.c > @@ -2111,7 +2111,11 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp) > print_fn_code(jit.prg_buf, jit.size_prg); > } > if (!fp->is_func || extra_pass) { > - bpf_jit_binary_lock_ro(header); > + if (bpf_jit_binary_lock_ro(header)) { > + bpf_jit_binary_free(header); > + fp = orig_fp; > + goto free_addrs; > + } > } else { > jit_data->header = header; > jit_data->ctx = jit; > diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c > index fa0759bfe498..73bf0aea8baf 100644 > --- a/arch/sparc/net/bpf_jit_comp_64.c > +++ b/arch/sparc/net/bpf_jit_comp_64.c > @@ -1602,7 +1602,11 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > bpf_flush_icache(header, (u8 *)header + header->size); > > if (!prog->is_func || extra_pass) { > - bpf_jit_binary_lock_ro(header); > + if (bpf_jit_binary_lock_ro(header)) { > + bpf_jit_binary_free(header); > + prog = orig_prog; > + goto out_off; > + } > } else { > jit_data->ctx = ctx; > jit_data->image = image_ptr; > diff --git a/arch/x86/net/bpf_jit_comp32.c b/arch/x86/net/bpf_jit_comp32.c > index b18ce19981ec..f2be1dcf3b24 100644 > --- a/arch/x86/net/bpf_jit_comp32.c > +++ b/arch/x86/net/bpf_jit_comp32.c > @@ -2600,8 +2600,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) > if (bpf_jit_enable > 1) > bpf_jit_dump(prog->len, proglen, pass + 1, image); > > - if (image) { > - bpf_jit_binary_lock_ro(header); > + if (image && !bpf_jit_binary_lock_ro(header)) { > prog->bpf_func = (void *)image; > prog->jited = 1; > prog->jited_len = proglen; > diff --git a/include/linux/filter.h b/include/linux/filter.h > index 7dd59bccaeec..fc42dcfdbd62 100644 > --- a/include/linux/filter.h > +++ b/include/linux/filter.h > @@ -895,10 +895,11 @@ static inline int __must_check bpf_prog_lock_ro(struct bpf_prog *fp) > return 0; > } > > -static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) > +static inline int __must_check > +bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) > { > set_vm_flush_reset_perms(hdr); > - set_memory_rox((unsigned long)hdr, hdr->size >> PAGE_SHIFT); > + return set_memory_rox((unsigned long)hdr, hdr->size >> PAGE_SHIFT); > } > > int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap);
