| Message ID | 20210903110702.588291-10-philmd@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | glib: Replace g_memdup() by g_memdup2_qemu() | expand |
On Fri, 3 Sep 2021 13:06:43 +0200 Philippe Mathieu-Daudé <philmd@redhat.com> wrote: > 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_qemu() wrapper. > > Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> Acked-by: Igor Mammedov <imammedo@redhat.com> > --- > hw/acpi/core.c | 3 ++- > hw/i386/acpi-build.c | 2 +- > 2 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/hw/acpi/core.c b/hw/acpi/core.c > index 1e004d0078d..9dd2cf09a0b 100644 > --- a/hw/acpi/core.c > +++ b/hw/acpi/core.c > @@ -637,7 +637,8 @@ void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent, > suspend[3] = 1 | ((!disable_s3) << 7); > suspend[4] = s4_val | ((!disable_s4) << 7); > > - fw_cfg_add_file(fw_cfg, "etc/system-states", g_memdup(suspend, 6), 6); > + fw_cfg_add_file(fw_cfg, "etc/system-states", > + g_memdup2_qemu(suspend, 6), 6); > } > } > > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c > index aa269914b49..54494ca1f65 100644 > --- a/hw/i386/acpi-build.c > +++ b/hw/i386/acpi-build.c > @@ -2785,7 +2785,7 @@ void acpi_setup(void) > */ > unsigned rsdp_size = acpi_data_len(tables.rsdp); > > - build_state->rsdp = g_memdup(tables.rsdp->data, rsdp_size); > + build_state->rsdp = g_memdup2_qemu(tables.rsdp->data, rsdp_size); > fw_cfg_add_file_callback(x86ms->fw_cfg, ACPI_BUILD_RSDP_FILE, > acpi_build_update, NULL, build_state, > build_state->rsdp, rsdp_size, true);
diff --git a/hw/acpi/core.c b/hw/acpi/core.c index 1e004d0078d..9dd2cf09a0b 100644 --- a/hw/acpi/core.c +++ b/hw/acpi/core.c @@ -637,7 +637,8 @@ void acpi_pm1_cnt_init(ACPIREGS *ar, MemoryRegion *parent, suspend[3] = 1 | ((!disable_s3) << 7); suspend[4] = s4_val | ((!disable_s4) << 7); - fw_cfg_add_file(fw_cfg, "etc/system-states", g_memdup(suspend, 6), 6); + fw_cfg_add_file(fw_cfg, "etc/system-states", + g_memdup2_qemu(suspend, 6), 6); } } diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c index aa269914b49..54494ca1f65 100644 --- a/hw/i386/acpi-build.c +++ b/hw/i386/acpi-build.c @@ -2785,7 +2785,7 @@ void acpi_setup(void) */ unsigned rsdp_size = acpi_data_len(tables.rsdp); - build_state->rsdp = g_memdup(tables.rsdp->data, rsdp_size); + build_state->rsdp = g_memdup2_qemu(tables.rsdp->data, rsdp_size); fw_cfg_add_file_callback(x86ms->fw_cfg, ACPI_BUILD_RSDP_FILE, acpi_build_update, NULL, build_state, build_state->rsdp, rsdp_size, true);
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_qemu() wrapper. Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> --- hw/acpi/core.c | 3 ++- hw/i386/acpi-build.c | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-)