[PATCH 6.9 065/222] bpf: Take return from set_memory_ro() into account with bpf_prog_lock_ro()

[PATCH 6.9 065/222] bpf: Take return from set_memory_ro() into account with bpf_prog_lock_ro()

[Greg Kroah-Hartman]

6.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Christophe Leroy <christophe.leroy@csgroup.eu>

[ Upstream commit 7d2cc63eca0c993c99d18893214abf8f85d566d8 ]

set_memory_ro() can fail, leaving memory unprotected.

Check its return and take it into account as an error.

Link: https://github.com/KSPP/linux/issues/7
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: linux-hardening@vger.kernel.org <linux-hardening@vger.kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Message-ID: <286def78955e04382b227cb3e4b6ba272a7442e3.1709850515.git.christophe.leroy@csgroup.eu>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/linux/filter.h | 5 +++--
 kernel/bpf/core.c      | 4 +++-
 kernel/bpf/verifier.c  | 8 ++++++--
 3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/include/linux/filter.h b/include/linux/filter.h
index 219ee7a768744..35791b1c61c7d 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -887,14 +887,15 @@ bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default)
 
 #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
 
-static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
+static inline int __must_check bpf_prog_lock_ro(struct bpf_prog *fp)
 {
 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
 	if (!fp->jited) {
 		set_vm_flush_reset_perms(fp);
-		set_memory_ro((unsigned long)fp, fp->pages);
+		return set_memory_ro((unsigned long)fp, fp->pages);
 	}
 #endif
+	return 0;
 }
 
 static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr)
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 1ea5ce5bb5993..9985988845e36 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -2403,7 +2403,9 @@ struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
 	}
 
 finalize:
-	bpf_prog_lock_ro(fp);
+	*err = bpf_prog_lock_ro(fp);
+	if (*err)
+		return fp;
 
 	/* The tail call compatibility check can only be done at
 	 * this late stage as we need to determine, if we deal
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index ab558eea1c9ee..d5fca9deac5a1 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -19354,10 +19354,14 @@ static int jit_subprogs(struct bpf_verifier_env *env)
 	 * bpf_prog_load will add the kallsyms for the main program.
 	 */
 	for (i = 1; i < env->subprog_cnt; i++) {
-		bpf_prog_lock_ro(func[i]);
-		bpf_prog_kallsyms_add(func[i]);
+		err = bpf_prog_lock_ro(func[i]);
+		if (err)
+			goto out_free;
 	}
 
+	for (i = 1; i < env->subprog_cnt; i++)
+		bpf_prog_kallsyms_add(func[i]);
+
 	/* Last step: make now unused interpreter insns from main
 	 * prog consistent for later dump requests, so they can
 	 * later look the same as if they were interpreted only.
-- 
2.43.0

[PATCH 6.9 066/222] bpf: Take return from set_memory_rox() into account with bpf_jit_binary_lock_ro()

[Greg Kroah-Hartman]

6.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Christophe Leroy <christophe.leroy@csgroup.eu>

[ Upstream commit e60adf513275c3a38e5cb67f7fd12387e43a3ff5 ]

set_memory_rox() can fail, leaving memory unprotected.

Check return and bail out when bpf_jit_binary_lock_ro() returns
an error.

Link: https://github.com/KSPP/linux/issues/7
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: linux-hardening@vger.kernel.org <linux-hardening@vger.kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Puranjay Mohan <puranjay12@gmail.com>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>  # s390x
Acked-by: Tiezhu Yang <yangtiezhu@loongson.cn>  # LoongArch
Reviewed-by: Johan Almbladh <johan.almbladh@anyfinetworks.com> # MIPS Part
Message-ID: <036b6393f23a2032ce75a1c92220b2afcb798d5d.1709850515.git.christophe.leroy@csgroup.eu>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 72b5cd697f5d9..deeb8f292454b 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -2252,28 +2252,21 @@ 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;
@@ -2290,5 +2283,11 @@ 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 e73323d759d0b..7dbefd4ba2107 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 a40d926b65139..e355dfca44008 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 d6ee2fd455503..979f45d4d1fbe 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 1d168a98ae21b..4be8f5cadd026 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -2112,7 +2112,11 @@ 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 fa0759bfe498e..73bf0aea8baf1 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 c10083a8e68e6..de0f9e5f9f73a 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 35791b1c61c7d..cf12bfa2a78cc 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -898,10 +898,11 @@ 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);
-- 
2.43.0