diff options
| author | Sachin Prabhu <sprabhu@redhat.com> | 2012-04-17 14:36:40 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-05-21 10:46:24 -0700 |
| commit | 4262cd1f4b734ea5fa05c37043c89106f38b2daa (patch) | |
| tree | b77f9f9f12808de450381e0227cda3666b646d9c | |
| parent | 6c9f63a43c30f496a37ade9fd4304c63df9b01bd (diff) | |
Avoid beyond bounds copy while caching ACL
commit 5794d21ef4639f0e33440927bb903f9598c21e92 upstream.
When attempting to cache ACLs returned from the server, if the bitmap
size + the ACL size is greater than a PAGE_SIZE but the ACL size itself
is smaller than a PAGE_SIZE, we can read past the buffer page boundary.
Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reported-by: Jian Li <jiali@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/nfs/nfs4proc.c | 12 |
1 files changed, 5 insertions, 7 deletions
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 2612223d96e..f3919dca02b 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -3532,16 +3532,16 @@ out: return ret; } -static void nfs4_write_cached_acl(struct inode *inode, const char *buf, size_t acl_len) +static void nfs4_write_cached_acl(struct inode *inode, struct page **pages, size_t pgbase, size_t acl_len) { struct nfs4_cached_acl *acl; - if (buf && acl_len <= PAGE_SIZE) { + if (pages && acl_len <= PAGE_SIZE) { acl = kmalloc(sizeof(*acl) + acl_len, GFP_KERNEL); if (acl == NULL) goto out; acl->cached = 1; - memcpy(acl->data, buf, acl_len); + _copy_from_pages(acl->data, pages, pgbase, acl_len); } else { acl = kmalloc(sizeof(*acl), GFP_KERNEL); if (acl == NULL) @@ -3574,7 +3574,6 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu struct nfs_getaclres res = { .acl_len = buflen, }; - void *resp_buf; struct rpc_message msg = { .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_GETACL], .rpc_argp = &args, @@ -3605,7 +3604,6 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu * the page we send as a guess */ if (buf == NULL) res.acl_flags |= NFS4_ACL_LEN_REQUEST; - resp_buf = page_address(pages[0]); dprintk("%s buf %p buflen %zu npages %d args.acl_len %zu\n", __func__, buf, buflen, npages, args.acl_len); @@ -3616,9 +3614,9 @@ static ssize_t __nfs4_get_acl_uncached(struct inode *inode, void *buf, size_t bu acl_len = res.acl_len - res.acl_data_offset; if (acl_len > args.acl_len) - nfs4_write_cached_acl(inode, NULL, acl_len); + nfs4_write_cached_acl(inode, NULL, 0, acl_len); else - nfs4_write_cached_acl(inode, resp_buf + res.acl_data_offset, + nfs4_write_cached_acl(inode, pages, res.acl_data_offset, acl_len); if (buf) { ret = -ERANGE; |