From: Jim Meyering <meyer...@redhat.com>

Each of the protocols[i].name strings (statically declared above)
has length less than 16, so this use of strncpy is misleading:
  strncpy(pSMB->DialectsArray+count, protocols[i].name, 16);
Besides, if a new name were added with length N >= 16, the existing
strncpy-using code would be buggy, creating a ->DialectsArray buffer
containing N-16+1 unset bytes where the NUL terminator should have
been.  Instead, traverse the name only once go get its length,
use a BUG_ON assertion to enforce the length restriction
and use memcpy to perform the copy.

Signed-off-by: Jim Meyering <meyer...@redhat.com>
---
 fs/cifs/cifssmb.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 074923c..16a9018 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -441,8 +441,10 @@ CIFSSMBNegotiate(const unsigned int xid, struct cifs_ses 
*ses)

        count = 0;
        for (i = 0; i < CIFS_NUM_PROT; i++) {
-               strncpy(pSMB->DialectsArray+count, protocols[i].name, 16);
-               count += strlen(protocols[i].name) + 1;
+               size_t len = strlen(protocols[i].name);
+               BUG_ON(len >= 16);
+               memcpy(pSMB->DialectsArray+count, protocols[i].name, len + 1);
+               count += len + 1;
                /* null at end of source and target buffers anyway */
        }
        inc_rfc1001_len(pSMB, count);
-- 
1.7.12

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