Re: [PATCH bpf-next v2 2/2] bpf: use kvmalloc for map keys in syscalls
From: Daniel Borkmann <daniel@iogearbox.net>
Date: 2021-08-18 22:24:45
Also in:
bpf
On 8/17/21 5:45 PM, Stanislav Fomichev wrote:
quoted hunk ↗ jump to hunk
Same as previous patch but for the keys. memdup_bpfptr is renamed to vmemdup_bpfptr (and converted to kvmalloc). Signed-off-by: Stanislav Fomichev <redacted> --- include/linux/bpfptr.h | 12 ++++++++++-- kernel/bpf/syscall.c | 34 +++++++++++++++++----------------- 2 files changed, 27 insertions(+), 19 deletions(-)diff --git a/include/linux/bpfptr.h b/include/linux/bpfptr.h index 5cdeab497cb3..84eeffb4316a 100644 --- a/include/linux/bpfptr.h +++ b/include/linux/bpfptr.h@@ -62,9 +62,17 @@ static inline int copy_to_bpfptr_offset(bpfptr_t dst, size_t offset, return copy_to_sockptr_offset((sockptr_t) dst, offset, src, size); } -static inline void *memdup_bpfptr(bpfptr_t src, size_t len) +static inline void *vmemdup_bpfptr(bpfptr_t src, size_t len)
nit: should we just name it kvmemdup_bpfptr() in that case?
{
- return memdup_sockptr((sockptr_t) src, len);
+ void *p = kvmalloc(len, GFP_USER | __GFP_NOWARN);
+
+ if (!p)
+ return ERR_PTR(-ENOMEM);
+ if (copy_from_sockptr(p, (sockptr_t) src, len)) {Also, I think this one should rather use copy_from_bpfptr() here.
+ kvfree(p); + return ERR_PTR(-EFAULT); + } + return p; }
Rest lgtm, thanks!