diff options
| author | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2023-06-23 11:43:14 -0400 |
|---|---|---|
| committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2023-08-23 15:58:47 -0400 |
| commit | 61182c796d74f54ba66d17bac6f516183ec09af2 (patch) | |
| tree | d33fc5c105f0b1198f63c6bf0fa7041c18bca164 /include/linux/sunrpc | |
| parent | 303a78052091c81e9003915c521fdca1c7e117af (diff) | |
SUNRPC: kmap() the xdr pages during decode
If the pages are in HIGHMEM then we need to make sure they're mapped
before trying to read data off of them, otherwise we could end up with a
NULL pointer dereference.
The downside to this is that we need an extra cleanup step at the end of
decode to kunmap() the last page. I introduced an xdr_finish_decode()
function to do this. Right now this function only calls the
unmap_current_page() function, but other generic cleanup steps could be
added in the future if we come across anything else.
Reported-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'include/linux/sunrpc')
| -rw-r--r-- | include/linux/sunrpc/xdr.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h index f89ec4b5ea16..adc844db1ea5 100644 --- a/include/linux/sunrpc/xdr.h +++ b/include/linux/sunrpc/xdr.h @@ -224,6 +224,7 @@ struct xdr_stream { struct kvec *iov; /* pointer to the current kvec */ struct kvec scratch; /* Scratch buffer */ struct page **page_ptr; /* pointer to the current page */ + void *page_kaddr; /* kmapped address of the current page */ unsigned int nwords; /* Remaining decode buffer length */ struct rpc_rqst *rqst; /* For debugging */ @@ -255,6 +256,7 @@ extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p, struct rpc_rqst *rqst); extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, struct page **pages, unsigned int len); +extern void xdr_finish_decode(struct xdr_stream *xdr); extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes); extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len); extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len); |