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    SubjectRe: [PATCH] cifs: remove misleading strncpy: each name has length < 16
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    Jim Meyering wrote:

    > From: Jim Meyering <meyering@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,

    s/go/to/, of course.

    > use a BUG_ON assertion to enforce the length restriction
    > and use memcpy to perform the copy.
    >
    > Signed-off-by: Jim Meyering <meyering@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);


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