Re: [PATCH v3 24/28] tests/qtest: Replace g_memdup() by g_memdup2()

[Laurent Vivier]

Le 03/09/2021 à 19:45, Philippe Mathieu-Daudé a écrit :
> Per 
> https://discourse.gnome.org/t/port-your-module-from-g-memdup-to-g-memdup2-now/5538
>
>    The old API took the size of the memory to duplicate as a guint,
>    whereas most memory functions take memory sizes as a gsize. This
>    made it easy to accidentally pass a gsize to g_memdup(). For large
>    values, that would lead to a silent truncation of the size from 64
>    to 32 bits, and result in a heap area being returned which is
>    significantly smaller than what the caller expects. This can likely
>    be exploited in various modules to cause a heap buffer overflow.
>
> Replace g_memdup() by the safer g_memdup2() wrapper.
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
>   tests/qtest/libqos/ahci.c   | 6 +++---
>   tests/qtest/libqos/qgraph.c | 2 +-
>   2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/tests/qtest/libqos/ahci.c b/tests/qtest/libqos/ahci.c
> index fba3e7a954e..eaa2096512e 100644
> --- a/tests/qtest/libqos/ahci.c
> +++ b/tests/qtest/libqos/ahci.c
> @@ -639,8 +639,8 @@ void ahci_exec(AHCIQState *ahci, uint8_t port,
>       AHCIOpts *opts;
>       uint64_t buffer_in;
>   
> -    opts = g_memdup((opts_in == NULL ? &default_opts : opts_in),
> -                    sizeof(AHCIOpts));
> +    opts = g_memdup2((opts_in == NULL ? &default_opts : opts_in),
> +                     sizeof(AHCIOpts));
>   
>       buffer_in = opts->buffer;
>   
> @@ -860,7 +860,7 @@ AHCICommand *ahci_command_create(uint8_t command_name)
>       g_assert(!props->ncq || props->lba48);
>   
>       /* Defaults and book-keeping */
> -    cmd->props = g_memdup(props, sizeof(AHCICommandProp));
> +    cmd->props = g_memdup2(props, sizeof(AHCICommandProp));
>       cmd->name = command_name;
>       cmd->xbytes = props->size;
>       cmd->prd_size = 4096;
> diff --git a/tests/qtest/libqos/qgraph.c b/tests/qtest/libqos/qgraph.c
> index d1dc4919305..109ff04e1e8 100644
> --- a/tests/qtest/libqos/qgraph.c
> +++ b/tests/qtest/libqos/qgraph.c
> @@ -93,7 +93,7 @@ static void add_edge(const char *source, const char *dest,
>       edge->type = type;
>       edge->dest = g_strdup(dest);
>       edge->edge_name = g_strdup(opts->edge_name ?: dest);
> -    edge->arg = g_memdup(opts->arg, opts->size_arg);
> +    edge->arg = g_memdup2(opts->arg, opts->size_arg);
>   
>       edge->before_cmd_line =
>           opts->before_cmd_line ? g_strconcat(" ", opts->before_cmd_line, NULL) 
> : NULL;

Applied to my trivial-patches branch.

Thanks,
Laurent