libxc: memory leak in handle_hvm_context

libxc: memory leak in handle_hvm_context

[Viktor Mitin]

Hi All,

It seems there is a memory leak in libxc function handle_hvm_context
(in file tools/libxc/xc_sr_restore_x86_hvm.c.). There is a malloc of
variable p without free.
Please take a look.

+/*
+ * Process an HVM_CONTEXT record from the stream.
+ */
+static int handle_hvm_context(struct xc_sr_context *ctx,
+                              struct xc_sr_record *rec)
+{
+    xc_interface *xch = ctx->xch;
+    void *p;
+
+    p = malloc(rec->length);
+    if ( !p )
+    {
+        ERROR("Unable to allocate %u bytes for hvm context", rec->length);
+        return -1;
+    }
+
+    free(ctx->x86_hvm.restore.context);
+
+    ctx->x86_hvm.restore.context = memcpy(p, rec->data, rec->length);
+    ctx->x86_hvm.restore.contextsz = rec->length;
+
+    return 0;
+}

Thanks

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[Xen-devel] libxc: memory leak in handle_hvm_context

[Viktor Mitin]

Hi All,

It seems there is a memory leak in libxc function handle_hvm_context
(in file tools/libxc/xc_sr_restore_x86_hvm.c.). There is a malloc of
variable p without free.
Please take a look.

+/*
+ * Process an HVM_CONTEXT record from the stream.
+ */
+static int handle_hvm_context(struct xc_sr_context *ctx,
+                              struct xc_sr_record *rec)
+{
+    xc_interface *xch = ctx->xch;
+    void *p;
+
+    p = malloc(rec->length);
+    if ( !p )
+    {
+        ERROR("Unable to allocate %u bytes for hvm context", rec->length);
+        return -1;
+    }
+
+    free(ctx->x86_hvm.restore.context);
+
+    ctx->x86_hvm.restore.context = memcpy(p, rec->data, rec->length);
+    ctx->x86_hvm.restore.contextsz = rec->length;
+
+    return 0;
+}

Thanks

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Re: libxc: memory leak in handle_hvm_context

[Viktor Mitin]

There is no memory leak in case when handle_hvm_context function is
called next time.
So the code seems ok, please ignore the mail, sorry for confusion.

Thanks

On Fri, May 17, 2019 at 2:49 PM Viktor Mitin <viktor.mitin.19@gmail.com> wrote:
>
> Hi All,
>
> It seems there is a memory leak in libxc function handle_hvm_context
> (in file tools/libxc/xc_sr_restore_x86_hvm.c.). There is a malloc of
> variable p without free.
> Please take a look.
>
> +/*
> + * Process an HVM_CONTEXT record from the stream.
> + */
> +static int handle_hvm_context(struct xc_sr_context *ctx,
> +                              struct xc_sr_record *rec)
> +{
> +    xc_interface *xch = ctx->xch;
> +    void *p;
> +
> +    p = malloc(rec->length);
> +    if ( !p )
> +    {
> +        ERROR("Unable to allocate %u bytes for hvm context", rec->length);
> +        return -1;
> +    }
> +
> +    free(ctx->x86_hvm.restore.context);
> +
> +    ctx->x86_hvm.restore.context = memcpy(p, rec->data, rec->length);
> +    ctx->x86_hvm.restore.contextsz = rec->length;
> +
> +    return 0;
> +}
>
> Thanks

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Re: [Xen-devel] libxc: memory leak in handle_hvm_context

[Viktor Mitin]

There is no memory leak in case when handle_hvm_context function is
called next time.
So the code seems ok, please ignore the mail, sorry for confusion.

Thanks

On Fri, May 17, 2019 at 2:49 PM Viktor Mitin <viktor.mitin.19@gmail.com> wrote:
>
> Hi All,
>
> It seems there is a memory leak in libxc function handle_hvm_context
> (in file tools/libxc/xc_sr_restore_x86_hvm.c.). There is a malloc of
> variable p without free.
> Please take a look.
>
> +/*
> + * Process an HVM_CONTEXT record from the stream.
> + */
> +static int handle_hvm_context(struct xc_sr_context *ctx,
> +                              struct xc_sr_record *rec)
> +{
> +    xc_interface *xch = ctx->xch;
> +    void *p;
> +
> +    p = malloc(rec->length);
> +    if ( !p )
> +    {
> +        ERROR("Unable to allocate %u bytes for hvm context", rec->length);
> +        return -1;
> +    }
> +
> +    free(ctx->x86_hvm.restore.context);
> +
> +    ctx->x86_hvm.restore.context = memcpy(p, rec->data, rec->length);
> +    ctx->x86_hvm.restore.contextsz = rec->length;
> +
> +    return 0;
> +}
>
> Thanks

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Re: libxc: memory leak in handle_hvm_context

[Andrew Cooper]

(Apologies for use of outlook - I'm having email problems atm).

There is no memory leak at all.

x = memcpy(y, ...);

is an "x = y;" assignment in disguise.  Recall that memcpy() returns y, and isn't a void function.

~Andrew
________________________________________
From: Viktor Mitin <viktor.mitin.19@gmail.com>
Sent: 17 May 2019 12:56
To: Andrew Cooper; Ian Campbell; xen-devel@lists.xenproject.org
Cc: Volodymyr Babchuk
Subject: Re: libxc: memory leak in handle_hvm_context

There is no memory leak in case when handle_hvm_context function is
called next time.
So the code seems ok, please ignore the mail, sorry for confusion.

Thanks

On Fri, May 17, 2019 at 2:49 PM Viktor Mitin <viktor.mitin.19@gmail.com> wrote:
>
> Hi All,
>
> It seems there is a memory leak in libxc function handle_hvm_context
> (in file tools/libxc/xc_sr_restore_x86_hvm.c.). There is a malloc of
> variable p without free.
> Please take a look.
>
> +/*
> + * Process an HVM_CONTEXT record from the stream.
> + */
> +static int handle_hvm_context(struct xc_sr_context *ctx,
> +                              struct xc_sr_record *rec)
> +{
> +    xc_interface *xch = ctx->xch;
> +    void *p;
> +
> +    p = malloc(rec->length);
> +    if ( !p )
> +    {
> +        ERROR("Unable to allocate %u bytes for hvm context", rec->length);
> +        return -1;
> +    }
> +
> +    free(ctx->x86_hvm.restore.context);
> +
> +    ctx->x86_hvm.restore.context = memcpy(p, rec->data, rec->length);
> +    ctx->x86_hvm.restore.contextsz = rec->length;
> +
> +    return 0;
> +}
>
> Thanks

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Re: [Xen-devel] libxc: memory leak in handle_hvm_context

[Andrew Cooper]

(Apologies for use of outlook - I'm having email problems atm).

There is no memory leak at all.

x = memcpy(y, ...);

is an "x = y;" assignment in disguise.  Recall that memcpy() returns y, and isn't a void function.

~Andrew
________________________________________
From: Viktor Mitin <viktor.mitin.19@gmail.com>
Sent: 17 May 2019 12:56
To: Andrew Cooper; Ian Campbell; xen-devel@lists.xenproject.org
Cc: Volodymyr Babchuk
Subject: Re: libxc: memory leak in handle_hvm_context

There is no memory leak in case when handle_hvm_context function is
called next time.
So the code seems ok, please ignore the mail, sorry for confusion.

Thanks

On Fri, May 17, 2019 at 2:49 PM Viktor Mitin <viktor.mitin.19@gmail.com> wrote:
>
> Hi All,
>
> It seems there is a memory leak in libxc function handle_hvm_context
> (in file tools/libxc/xc_sr_restore_x86_hvm.c.). There is a malloc of
> variable p without free.
> Please take a look.
>
> +/*
> + * Process an HVM_CONTEXT record from the stream.
> + */
> +static int handle_hvm_context(struct xc_sr_context *ctx,
> +                              struct xc_sr_record *rec)
> +{
> +    xc_interface *xch = ctx->xch;
> +    void *p;
> +
> +    p = malloc(rec->length);
> +    if ( !p )
> +    {
> +        ERROR("Unable to allocate %u bytes for hvm context", rec->length);
> +        return -1;
> +    }
> +
> +    free(ctx->x86_hvm.restore.context);
> +
> +    ctx->x86_hvm.restore.context = memcpy(p, rec->data, rec->length);
> +    ctx->x86_hvm.restore.contextsz = rec->length;
> +
> +    return 0;
> +}
>
> Thanks

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