diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-12-21 12:02:36 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-12-21 12:02:36 -0800 |
| commit | 5dbdc4c565e31a3b9899f55bc6dc5f840276a04e (patch) | |
| tree | 1cd6f15320e626ea68f0dd0211612724a2ccbd70 | |
| parent | 1c3e979bf3e225e5b4b810b24712b16254d608b6 (diff) | |
| parent | 53b1119a6e5028b125f431a0116ba73510d82a72 (diff) | |
Merge tag 'nfsd-5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
Pull nfsd fix from Chuck Lever:
"Address a buffer overrun reported by Anatoly Trosinenko"
* tag 'nfsd-5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
NFSD: Fix READDIR buffer overflow
| -rw-r--r-- | fs/nfsd/nfs3proc.c | 11 | ||||
| -rw-r--r-- | fs/nfsd/nfsproc.c | 8 |
2 files changed, 8 insertions, 11 deletions
diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c index 4418517f6f12..15dac36ca852 100644 --- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -438,22 +438,19 @@ nfsd3_proc_link(struct svc_rqst *rqstp) static void nfsd3_init_dirlist_pages(struct svc_rqst *rqstp, struct nfsd3_readdirres *resp, - int count) + u32 count) { struct xdr_buf *buf = &resp->dirlist; struct xdr_stream *xdr = &resp->xdr; - count = min_t(u32, count, svc_max_payload(rqstp)); + count = clamp(count, (u32)(XDR_UNIT * 2), svc_max_payload(rqstp)); memset(buf, 0, sizeof(*buf)); /* Reserve room for the NULL ptr & eof flag (-2 words) */ buf->buflen = count - XDR_UNIT * 2; buf->pages = rqstp->rq_next_page; - while (count > 0) { - rqstp->rq_next_page++; - count -= PAGE_SIZE; - } + rqstp->rq_next_page += (buf->buflen + PAGE_SIZE - 1) >> PAGE_SHIFT; /* This is xdr_init_encode(), but it assumes that * the head kvec has already been consumed. */ @@ -462,7 +459,7 @@ static void nfsd3_init_dirlist_pages(struct svc_rqst *rqstp, xdr->page_ptr = buf->pages; xdr->iov = NULL; xdr->p = page_address(*buf->pages); - xdr->end = xdr->p + (PAGE_SIZE >> 2); + xdr->end = (void *)xdr->p + min_t(u32, buf->buflen, PAGE_SIZE); xdr->rqst = NULL; } diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c index eea5b59b6a6c..de282f3273c5 100644 --- a/fs/nfsd/nfsproc.c +++ b/fs/nfsd/nfsproc.c @@ -556,17 +556,17 @@ nfsd_proc_rmdir(struct svc_rqst *rqstp) static void nfsd_init_dirlist_pages(struct svc_rqst *rqstp, struct nfsd_readdirres *resp, - int count) + u32 count) { struct xdr_buf *buf = &resp->dirlist; struct xdr_stream *xdr = &resp->xdr; - count = min_t(u32, count, PAGE_SIZE); + count = clamp(count, (u32)(XDR_UNIT * 2), svc_max_payload(rqstp)); memset(buf, 0, sizeof(*buf)); /* Reserve room for the NULL ptr & eof flag (-2 words) */ - buf->buflen = count - sizeof(__be32) * 2; + buf->buflen = count - XDR_UNIT * 2; buf->pages = rqstp->rq_next_page; rqstp->rq_next_page++; @@ -577,7 +577,7 @@ static void nfsd_init_dirlist_pages(struct svc_rqst *rqstp, xdr->page_ptr = buf->pages; xdr->iov = NULL; xdr->p = page_address(*buf->pages); - xdr->end = xdr->p + (PAGE_SIZE >> 2); + xdr->end = (void *)xdr->p + min_t(u32, buf->buflen, PAGE_SIZE); xdr->rqst = NULL; } |