Merge tag '4.19-rc3-smb3-cifs' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Fixes for four CIFS/SMB3 potential pointer overflow issues, one minor
build fix, and a build warning cleanup"
* tag '4.19-rc3-smb3-cifs' of git://git.samba.org/sfrench/cifs-2.6:
cifs: read overflow in is_valid_oplock_break()
cifs: integer overflow in in SMB2_ioctl()
CIFS: fix wrapping bugs in num_entries()
cifs: prevent integer overflow in nxt_dir_entry()
fs/cifs: require sha512
fs/cifs: suppress a string overflow warning
diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index 35c83fe..abcd78e 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -6,6 +6,7 @@
select CRYPTO_MD4
select CRYPTO_MD5
select CRYPTO_SHA256
+ select CRYPTO_SHA512
select CRYPTO_CMAC
select CRYPTO_HMAC
select CRYPTO_ARC4
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index dc2f4cf..5657b79 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -601,10 +601,15 @@
}
count = 0;
+ /*
+ * We know that all the name entries in the protocols array
+ * are short (< 16 bytes anyway) and are NUL terminated.
+ */
for (i = 0; i < CIFS_NUM_PROT; i++) {
- strncpy(pSMB->DialectsArray+count, protocols[i].name, 16);
- count += strlen(protocols[i].name) + 1;
- /* null at end of source and target buffers anyway */
+ size_t len = strlen(protocols[i].name) + 1;
+
+ memcpy(pSMB->DialectsArray+count, protocols[i].name, len);
+ count += len;
}
inc_rfc1001_len(pSMB, count);
pSMB->ByteCount = cpu_to_le16(count);
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index dacb2c0..6926685 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -402,9 +402,17 @@
(struct smb_com_transaction_change_notify_rsp *)buf;
struct file_notify_information *pnotify;
__u32 data_offset = 0;
+ size_t len = srv->total_read - sizeof(pSMBr->hdr.smb_buf_length);
+
if (get_bcc(buf) > sizeof(struct file_notify_information)) {
data_offset = le32_to_cpu(pSMBr->DataOffset);
+ if (data_offset >
+ len - sizeof(struct file_notify_information)) {
+ cifs_dbg(FYI, "invalid data_offset %u\n",
+ data_offset);
+ return true;
+ }
pnotify = (struct file_notify_information *)
((char *)&pSMBr->hdr.Protocol + data_offset);
cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n",
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index eeab81c..e169e1a 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -376,8 +376,15 @@
new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
pfData->FileNameLength;
- } else
- new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
+ } else {
+ u32 next_offset = le32_to_cpu(pDirInfo->NextEntryOffset);
+
+ if (old_entry + next_offset < old_entry) {
+ cifs_dbg(VFS, "invalid offset %u\n", next_offset);
+ return NULL;
+ }
+ new_entry = old_entry + next_offset;
+ }
cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry);
/* validate that new_entry is not past end of SMB */
if (new_entry >= end_of_smb) {
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index c08acfc..f54d07b 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -2459,14 +2459,14 @@
/* We check for obvious errors in the output buffer length and offset */
if (*plen == 0)
goto ioctl_exit; /* server returned no data */
- else if (*plen > 0xFF00) {
+ else if (*plen > rsp_iov.iov_len || *plen > 0xFF00) {
cifs_dbg(VFS, "srv returned invalid ioctl length: %d\n", *plen);
*plen = 0;
rc = -EIO;
goto ioctl_exit;
}
- if (rsp_iov.iov_len < le32_to_cpu(rsp->OutputOffset) + *plen) {
+ if (rsp_iov.iov_len - *plen < le32_to_cpu(rsp->OutputOffset)) {
cifs_dbg(VFS, "Malformed ioctl resp: len %d offset %d\n", *plen,
le32_to_cpu(rsp->OutputOffset));
*plen = 0;
@@ -3577,33 +3577,38 @@
int len;
unsigned int entrycount = 0;
unsigned int next_offset = 0;
- FILE_DIRECTORY_INFO *entryptr;
+ char *entryptr;
+ FILE_DIRECTORY_INFO *dir_info;
if (bufstart == NULL)
return 0;
- entryptr = (FILE_DIRECTORY_INFO *)bufstart;
+ entryptr = bufstart;
while (1) {
- entryptr = (FILE_DIRECTORY_INFO *)
- ((char *)entryptr + next_offset);
-
- if ((char *)entryptr + size > end_of_buf) {
+ if (entryptr + next_offset < entryptr ||
+ entryptr + next_offset > end_of_buf ||
+ entryptr + next_offset + size > end_of_buf) {
cifs_dbg(VFS, "malformed search entry would overflow\n");
break;
}
- len = le32_to_cpu(entryptr->FileNameLength);
- if ((char *)entryptr + len + size > end_of_buf) {
+ entryptr = entryptr + next_offset;
+ dir_info = (FILE_DIRECTORY_INFO *)entryptr;
+
+ len = le32_to_cpu(dir_info->FileNameLength);
+ if (entryptr + len < entryptr ||
+ entryptr + len > end_of_buf ||
+ entryptr + len + size > end_of_buf) {
cifs_dbg(VFS, "directory entry name would overflow frame end of buf %p\n",
end_of_buf);
break;
}
- *lastentry = (char *)entryptr;
+ *lastentry = entryptr;
entrycount++;
- next_offset = le32_to_cpu(entryptr->NextEntryOffset);
+ next_offset = le32_to_cpu(dir_info->NextEntryOffset);
if (!next_offset)
break;
}
