| Message ID | 1535019842-18103-1-git-send-email-hofrat@osadl.org |
|---|---|
| State | New |
| Headers | show |
| Series | cifs: check kmalloc before use | expand |
merged into cifs-2.6.git for-next On Thu, Aug 23, 2018 at 11:02 AM Nicholas Mc Guire <hofrat@osadl.org> wrote: > > The kmalloc was not being checked - if it fails issue a warning > and return -ENOMEM to the caller. > > Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> > Fixes: b8da344b74c8 ("cifs: dynamic allocation of ntlmssp blob") > --- > > Problem was located with an experimental coccinelle script > > Both call-sites will expect non-0 to indicate error so -ENOMEM > should be OK here. Setting buflen to 0 seems to be the expected > behavior on failure although it will not be checked/used at > the call-sites - probably this could be removed here as well as > in the handling of authentication error (preceding this change) > it was just retained for consistency. > > Patch was compile tested with: x86_64_defconfig + CONFIG_CIFS=y > (with sparse and smatch warning unrelated to proposed change) > > Patch is against 4.18 (localversion-next is next-20180823) > > fs/cifs/sess.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c > index 8b0502c..aa23c00 100644 > --- a/fs/cifs/sess.c > +++ b/fs/cifs/sess.c > @@ -398,6 +398,12 @@ int build_ntlmssp_auth_blob(unsigned char **pbuffer, > goto setup_ntlmv2_ret; > } > *pbuffer = kmalloc(size_of_ntlmssp_blob(ses), GFP_KERNEL); > + if (!*pbuffer) { > + rc = -ENOMEM; > + cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc); > + *buflen = 0; > + goto setup_ntlmv2_ret; > + } > sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer; > > memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8); > -- > 2.1.4 >
diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index 8b0502c..aa23c00 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -398,6 +398,12 @@ int build_ntlmssp_auth_blob(unsigned char **pbuffer, goto setup_ntlmv2_ret; } *pbuffer = kmalloc(size_of_ntlmssp_blob(ses), GFP_KERNEL); + if (!*pbuffer) { + rc = -ENOMEM; + cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc); + *buflen = 0; + goto setup_ntlmv2_ret; + } sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer; memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
The kmalloc was not being checked - if it fails issue a warning and return -ENOMEM to the caller. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Fixes: b8da344b74c8 ("cifs: dynamic allocation of ntlmssp blob") --- Problem was located with an experimental coccinelle script Both call-sites will expect non-0 to indicate error so -ENOMEM should be OK here. Setting buflen to 0 seems to be the expected behavior on failure although it will not be checked/used at the call-sites - probably this could be removed here as well as in the handling of authentication error (preceding this change) it was just retained for consistency. Patch was compile tested with: x86_64_defconfig + CONFIG_CIFS=y (with sparse and smatch warning unrelated to proposed change) Patch is against 4.18 (localversion-next is next-20180823) fs/cifs/sess.c | 6 ++++++ 1 file changed, 6 insertions(+)