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-rw-r--r--arch/arm/net/bpf_jit_32.c3
-rw-r--r--arch/mips/net/bpf_jit.c3
-rw-r--r--arch/powerpc/net/bpf_jit_comp.c3
-rw-r--r--arch/s390/net/bpf_jit_comp.c2
-rw-r--r--arch/sparc/net/bpf_jit_comp.c3
-rw-r--r--arch/x86/net/bpf_jit_comp.c18
-rw-r--r--include/linux/filter.h49
-rw-r--r--kernel/bpf/core.c80
-rw-r--r--kernel/seccomp.c7
-rw-r--r--lib/test_bpf.c2
-rw-r--r--net/core/filter.c6
11 files changed, 144 insertions, 32 deletions
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
index a37b989a2f91..a76623bcf722 100644
--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -930,5 +930,6 @@ void bpf_jit_free(struct bpf_prog *fp)
{
if (fp->jited)
module_free(NULL, fp->bpf_func);
- kfree(fp);
+
+ bpf_prog_unlock_free(fp);
}
diff --git a/arch/mips/net/bpf_jit.c b/arch/mips/net/bpf_jit.c
index 05a56619ece2..cfa83cf2447d 100644
--- a/arch/mips/net/bpf_jit.c
+++ b/arch/mips/net/bpf_jit.c
@@ -1427,5 +1427,6 @@ void bpf_jit_free(struct bpf_prog *fp)
{
if (fp->jited)
module_free(NULL, fp->bpf_func);
- kfree(fp);
+
+ bpf_prog_unlock_free(fp);
}
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 3afa6f4c1957..40c53ff59124 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -697,5 +697,6 @@ void bpf_jit_free(struct bpf_prog *fp)
{
if (fp->jited)
module_free(NULL, fp->bpf_func);
- kfree(fp);
+
+ bpf_prog_unlock_free(fp);
}
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 61e45b7c04d7..f2833c5b218a 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -887,5 +887,5 @@ void bpf_jit_free(struct bpf_prog *fp)
module_free(NULL, header);
free_filter:
- kfree(fp);
+ bpf_prog_unlock_free(fp);
}
diff --git a/arch/sparc/net/bpf_jit_comp.c b/arch/sparc/net/bpf_jit_comp.c
index 1f76c22a6a75..f7a736b645e8 100644
--- a/arch/sparc/net/bpf_jit_comp.c
+++ b/arch/sparc/net/bpf_jit_comp.c
@@ -812,5 +812,6 @@ void bpf_jit_free(struct bpf_prog *fp)
{
if (fp->jited)
module_free(NULL, fp->bpf_func);
- kfree(fp);
+
+ bpf_prog_unlock_free(fp);
}
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index b08a98c59530..39ccfbb4a723 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -972,23 +972,17 @@ out:
kfree(addrs);
}
-static void bpf_jit_free_deferred(struct work_struct *work)
+void bpf_jit_free(struct bpf_prog *fp)
{
- struct bpf_prog *fp = container_of(work, struct bpf_prog, work);
unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK;
struct bpf_binary_header *header = (void *)addr;
+ if (!fp->jited)
+ goto free_filter;
+
set_memory_rw(addr, header->pages);
module_free(NULL, header);
- kfree(fp);
-}
-void bpf_jit_free(struct bpf_prog *fp)
-{
- if (fp->jited) {
- INIT_WORK(&fp->work, bpf_jit_free_deferred);
- schedule_work(&fp->work);
- } else {
- kfree(fp);
- }
+free_filter:
+ bpf_prog_unlock_free(fp);
}
diff --git a/include/linux/filter.h b/include/linux/filter.h
index a5227ab8ccb1..c78994593355 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -9,6 +9,11 @@
#include <linux/skbuff.h>
#include <linux/workqueue.h>
#include <uapi/linux/filter.h>
+#include <asm/cacheflush.h>
+
+struct sk_buff;
+struct sock;
+struct seccomp_data;
/* Internally used and optimized filter representation with extended
* instruction set based on top of classic BPF.
@@ -320,20 +325,23 @@ struct sock_fprog_kern {
struct sock_filter *filter;
};
-struct sk_buff;
-struct sock;
-struct seccomp_data;
+struct bpf_work_struct {
+ struct bpf_prog *prog;
+ struct work_struct work;
+};
struct bpf_prog {
+ u32 pages; /* Number of allocated pages */
u32 jited:1, /* Is our filter JIT'ed? */
len:31; /* Number of filter blocks */
struct sock_fprog_kern *orig_prog; /* Original BPF program */
+ struct bpf_work_struct *work; /* Deferred free work struct */
unsigned int (*bpf_func)(const struct sk_buff *skb,
const struct bpf_insn *filter);
+ /* Instructions for interpreter */
union {
struct sock_filter insns[0];
struct bpf_insn insnsi[0];
- struct work_struct work;
};
};
@@ -353,6 +361,26 @@ static inline unsigned int bpf_prog_size(unsigned int proglen)
#define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0]))
+#ifdef CONFIG_DEBUG_SET_MODULE_RONX
+static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
+{
+ 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);
+}
+#else
+static inline void bpf_prog_lock_ro(struct bpf_prog *fp)
+{
+}
+
+static inline void bpf_prog_unlock_ro(struct bpf_prog *fp)
+{
+}
+#endif /* CONFIG_DEBUG_SET_MODULE_RONX */
+
int sk_filter(struct sock *sk, struct sk_buff *skb);
void bpf_prog_select_runtime(struct bpf_prog *fp);
@@ -361,6 +389,17 @@ void bpf_prog_free(struct bpf_prog *fp);
int bpf_convert_filter(struct sock_filter *prog, int len,
struct bpf_insn *new_prog, int *new_len);
+struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
+struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
+ gfp_t gfp_extra_flags);
+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);
+}
+
int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog);
void bpf_prog_destroy(struct bpf_prog *fp);
@@ -450,7 +489,7 @@ static inline void bpf_jit_compile(struct bpf_prog *fp)
static inline void bpf_jit_free(struct bpf_prog *fp)
{
- kfree(fp);
+ bpf_prog_unlock_free(fp);
}
#endif /* CONFIG_BPF_JIT */
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 7f0dbcbb34af..b54bb2c2e494 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -22,6 +22,7 @@
*/
#include <linux/filter.h>
#include <linux/skbuff.h>
+#include <linux/vmalloc.h>
#include <asm/unaligned.h>
/* Registers */
@@ -63,6 +64,67 @@ void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, uns
return NULL;
}
+struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
+{
+ gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO |
+ gfp_extra_flags;
+ struct bpf_work_struct *ws;
+ struct bpf_prog *fp;
+
+ size = round_up(size, PAGE_SIZE);
+ fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
+ if (fp == NULL)
+ return NULL;
+
+ ws = kmalloc(sizeof(*ws), GFP_KERNEL | gfp_extra_flags);
+ if (ws == NULL) {
+ vfree(fp);
+ return NULL;
+ }
+
+ fp->pages = size / PAGE_SIZE;
+ fp->work = ws;
+
+ return fp;
+}
+EXPORT_SYMBOL_GPL(bpf_prog_alloc);
+
+struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
+ gfp_t gfp_extra_flags)
+{
+ gfp_t gfp_flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO |
+ gfp_extra_flags;
+ struct bpf_prog *fp;
+
+ BUG_ON(fp_old == NULL);
+
+ size = round_up(size, PAGE_SIZE);
+ if (size <= fp_old->pages * PAGE_SIZE)
+ return fp_old;
+
+ fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
+ if (fp != NULL) {
+ memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
+ fp->pages = size / PAGE_SIZE;
+
+ /* We keep fp->work from fp_old around in the new
+ * reallocated structure.
+ */
+ fp_old->work = NULL;
+ __bpf_prog_free(fp_old);
+ }
+
+ return fp;
+}
+EXPORT_SYMBOL_GPL(bpf_prog_realloc);
+
+void __bpf_prog_free(struct bpf_prog *fp)
+{
+ kfree(fp->work);
+ vfree(fp);
+}
+EXPORT_SYMBOL_GPL(__bpf_prog_free);
+
/* Base function for offset calculation. Needs to go into .text section,
* therefore keeping it non-static as well; will also be used by JITs
* anyway later on, so do not let the compiler omit it.
@@ -523,12 +585,26 @@ void bpf_prog_select_runtime(struct bpf_prog *fp)
/* Probe if internal BPF can be JITed */
bpf_int_jit_compile(fp);
+ /* Lock whole bpf_prog as read-only */
+ bpf_prog_lock_ro(fp);
}
EXPORT_SYMBOL_GPL(bpf_prog_select_runtime);
-/* free internal BPF program */
+static void bpf_prog_free_deferred(struct work_struct *work)
+{
+ struct bpf_work_struct *ws;
+
+ ws = container_of(work, struct bpf_work_struct, work);
+ bpf_jit_free(ws->prog);
+}
+
+/* Free internal BPF program */
void bpf_prog_free(struct bpf_prog *fp)
{
- bpf_jit_free(fp);
+ struct bpf_work_struct *ws = fp->work;
+
+ INIT_WORK(&ws->work, bpf_prog_free_deferred);
+ ws->prog = fp;
+ schedule_work(&ws->work);
}
EXPORT_SYMBOL_GPL(bpf_prog_free);
diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 44eb005c6695..84922befea84 100644
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -395,16 +395,15 @@ static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog)
if (!filter)
goto free_prog;
- filter->prog = kzalloc(bpf_prog_size(new_len),
- GFP_KERNEL|__GFP_NOWARN);
+ filter->prog = bpf_prog_alloc(bpf_prog_size(new_len), __GFP_NOWARN);
if (!filter->prog)
goto free_filter;
ret = bpf_convert_filter(fp, fprog->len, filter->prog->insnsi, &new_len);
if (ret)
goto free_filter_prog;
- kfree(fp);
+ kfree(fp);
atomic_set(&filter->usage, 1);
filter->prog->len = new_len;
@@ -413,7 +412,7 @@ static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog)
return filter;
free_filter_prog:
- kfree(filter->prog);
+ __bpf_prog_free(filter->prog);
free_filter:
kfree(filter);
free_prog:
diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index 8c66c6aace04..9a67456ba29a 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -1836,7 +1836,7 @@ static struct bpf_prog *generate_filter(int which, int *err)
break;
case INTERNAL:
- fp = kzalloc(bpf_prog_size(flen), GFP_KERNEL);
+ fp = bpf_prog_alloc(bpf_prog_size(flen), 0);
if (fp == NULL) {
pr_cont("UNEXPECTED_FAIL no memory left\n");
*err = -ENOMEM;
diff --git a/net/core/filter.c b/net/core/filter.c
index d814b8a89d0f..37f8eb06fdee 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -933,7 +933,7 @@ static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
/* Expand fp for appending the new filter representation. */
old_fp = fp;
- fp = krealloc(old_fp, bpf_prog_size(new_len), GFP_KERNEL);
+ fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
if (!fp) {
/* The old_fp is still around in case we couldn't
* allocate new memory, so uncharge on that one.
@@ -1013,7 +1013,7 @@ int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
if (fprog->filter == NULL)
return -EINVAL;
- fp = kmalloc(bpf_prog_size(fprog->len), GFP_KERNEL);
+ fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
if (!fp)
return -ENOMEM;
@@ -1069,7 +1069,7 @@ int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
if (fprog->filter == NULL)
return -EINVAL;
- prog = kmalloc(bpf_fsize, GFP_KERNEL);
+ prog = bpf_prog_alloc(bpf_fsize, 0);
if (!prog)
return -ENOMEM;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 16:12:30 +0000