[PATCH v2 28/29] x86/mm: Report actual image regions in /proc/iomem
From: Kees Cook <hidden>
Date: 2019-10-11 00:06:42
Also in:
linux-alpha, linux-arch, linux-arm-kernel, linux-s390, lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
The resource reservations in /proc/iomem made for the kernel image did not reflect the gaps between text, rodata, and data. Add the "rodata" resource and update the start/end calculations to match the respective calls to free_kernel_image_pages(). Before (booted with "nokaslr" for easier comparison): 00100000-bffd9fff : System RAM 01000000-01e011d0 : Kernel code 01e011d1-025619bf : Kernel data 02a95000-035fffff : Kernel bss After: 00100000-bffd9fff : System RAM 01000000-01e011d0 : Kernel code 02000000-023d4fff : Kernel rodata 02400000-025619ff : Kernel data 02a95000-035fffff : Kernel bss Signed-off-by: Kees Cook <redacted> --- arch/x86/kernel/setup.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 77ea96b794bd..591e885a852e 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c@@ -143,6 +143,13 @@ struct boot_params boot_params; /* * Machine setup.. */ +static struct resource rodata_resource = { + .name = "Kernel rodata", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM +}; + static struct resource data_resource = { .name = "Kernel data", .start = 0,
@@ -951,7 +958,9 @@ void __init setup_arch(char **cmdline_p) code_resource.start = __pa_symbol(_text); code_resource.end = __pa_symbol(_etext)-1; - data_resource.start = __pa_symbol(_etext); + rodata_resource.start = __pa_symbol(__start_rodata); + rodata_resource.end = __pa_symbol(__end_rodata)-1; + data_resource.start = __pa_symbol(_sdata); data_resource.end = __pa_symbol(_edata)-1; bss_resource.start = __pa_symbol(__bss_start); bss_resource.end = __pa_symbol(__bss_stop)-1;
@@ -1040,6 +1049,7 @@ void __init setup_arch(char **cmdline_p) /* after parse_early_param, so could debug it */ insert_resource(&iomem_resource, &code_resource); + insert_resource(&iomem_resource, &rodata_resource); insert_resource(&iomem_resource, &data_resource); insert_resource(&iomem_resource, &bss_resource);
--
2.17.1