diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/core.c | 80 | ||||
| -rw-r--r-- | kernel/crash_dump.c | 1 | ||||
| -rw-r--r-- | kernel/seccomp.c | 7 |
3 files changed, 82 insertions, 6 deletions
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/crash_dump.c b/kernel/crash_dump.c index c766ee54c0b1..b64e238b553b 100644 --- a/kernel/crash_dump.c +++ b/kernel/crash_dump.c @@ -18,6 +18,7 @@ unsigned long saved_max_pfn; * it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE. */ unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX; +EXPORT_SYMBOL_GPL(elfcorehdr_addr); /* * stores the size of elf header of crash image 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: |