x86/boot/KASLR: Restrict kernel to be randomized in mirror regions
v2 cover x86/boot/KASLR: Restrict kernel to be randomized in mirror regions
Our customer reported that Kernel text may be located on non-mirror region (movable zone) when both address range mirroring feature and KASLR are enabled.
The functions of address range mirroring feature are as follows.
- The physical memory region whose descriptors in EFI memory map have EFI_MEMORY_MORE_RELIABLE attribute (bit: 16) are mirrored
- The function arranges such mirror region into normal zone and other region into movable zone in order to locate kernel code and data on mirror region
So we need restrict kernel to be located inside mirror regions if it is existed.
The method is very simple. If efi is enabled, just iterate all efi memory map and pick mirror region to process for adding candidate of slot. If efi disabled or no mirror region existed, still process e820 memory map. This won't bring much efficiency loss, at worst we just go through all efi memory maps and found no mirror.
v1->v2:
Removed debug code.
Taku suggested that we should put kernel to mirrored region always whether or not "kernelcore=mirror" is specified since kernel text is important and mirrored region is reliable.
Change code according to kbuild report and Chao Fan's comment.
Test:
Chao has tested the v1 (RFC patchset) 100 times. And he said in the 100 times, 50 times are with this patchset applied, 50 times are without it. The test result showed the v1 patchset works very well.
Baoquan He (2):
x86/boot/KASLR: Adapt process_e820_entry for any type of memory entry x86/boot/KASLR: Restrict kernel to be randomized in mirror regions
arch/x86/boot/compressed/kaslr.c | 108 +++++++++++++++++++++++++++++---------- 1 file changed, 82 insertions(+), 26 deletions(-)
Signature · 1 line
2.5.5
PATCH v2 1/2 x86/boot/KASLR: Adapt process_e820_entry for any type of memory entry
Now function process_e820_entry is only used to process e820 memory entries. Adapt it for any type of memory entry, not just for e820. Later we will use it to process efi mirror regions.
So rename the old process_e820_entry to process_mem_region, and extract and wrap the e820 specific processing code into process_e820_entry.
--- arch/x86/boot/compressed/kaslr.c | 60 ++++++++++++++++++++++------------------ 1 file changed, 33 insertions(+), 27 deletions(-)
arch/x86/boot/compressed/kaslr.c +33 -27
@@ -479,35 +479,31 @@ static unsigned long slots_fetch_random(void)return 0 ; } -static void process_e820_entry (struct boot_e820_entry *entry, +static void process_mem_region (struct mem_vector *entry,unsigned long minimum,unsigned long image_size) {struct mem_vector region, overlap;struct slot_area slot_area;unsigned long start_orig, end; -struct boot_e820_entry cur_entry; - -/* Skip non-RAM entries. */ -if (entry->type !=E820_TYPE_RAM ) -return ; +struct mem_vector cur_entry;/* On 32-bit, ignore entries entirely above our maximum. */ -if (IS_ENABLED (CONFIG_X86_32 ) && entry->addr >=KERNEL_IMAGE_SIZE ) +if (IS_ENABLED (CONFIG_X86_32 ) && entry->start >=KERNEL_IMAGE_SIZE )return ;/* Ignore entries entirely below our minimum. */ -if (entry->addr + entry->size < minimum) +if (entry->start + entry->size < minimum)return ;/* Ignore entries above memory limit */ - end =min (entry->size + entry->addr, mem_limit); -if (entry->addr >= end) + end =min (entry->size + entry->start, mem_limit); +if (entry->start >= end)return ; - cur_entry.addr = entry->addr; - cur_entry.size = end - entry->addr; + cur_entry.start = entry->start; + cur_entry.size = end - entry->start; - region.start = cur_entry.addr; + region.start = cur_entry.start; region.size = cur_entry.size;/* Give up if slot area array is full. */
@@ -522,7 +518,7 @@ static void process_e820_entry(struct boot_e820_entry *entry, region.start =ALIGN (region.start,CONFIG_PHYSICAL_ALIGN );/* Did we raise the address above this e820 region? */ -if (region.start > cur_entry.addr + cur_entry.size) +if (region.start > cur_entry.start + cur_entry.size)return ;/* Reduce size by any delta from the original address. */
@@ -562,12 +558,31 @@ static void process_e820_entry(struct boot_e820_entry *entry, } } -static unsigned long find_random_phys_addr (unsigned long minimum, -unsigned long image_size) +static void process_e820_entry (unsigned long minimum,unsigned long image_size) {int i; -unsigned long addr; +struct mem_vector region; +struct boot_e820_entry *entry; + +/* Verify potential e820 positions, appending to slots list. */ +for (i =0 ; i < boot_params->e820_entries; i++) { + entry = &boot_params->e820_table[i]; +/* Skip non-RAM entries. */ +if (entry->type !=E820_TYPE_RAM ) +continue ; + region.start = entry->addr; + region.size = entry->size; +process_mem_region (®ion, minimum, image_size); +if (slot_area_index ==MAX_SLOT_AREA ) { +debug_putstr ("Aborted e820 scan (slot_areas full)!\n" ); +break ; + } + } +} +static unsigned long find_random_phys_addr (unsigned long minimum, +unsigned long image_size) +{/* Check if we had too many memmaps. */ if (memmap_too_large) {debug_putstr ("Aborted e820 scan (more than 4 memmap= args)!\n" );
@@ -577,16 +592,7 @@ static unsigned long find_random_phys_addr(unsigned long minimum,/* Make sure minimum is aligned. */ minimum =ALIGN (minimum,CONFIG_PHYSICAL_ALIGN ); -/* Verify potential e820 positions, appending to slots list. */ -for (i =0 ; i < boot_params->e820_entries; i++) { -process_e820_entry (&boot_params->e820_table[i], minimum, - image_size); -if (slot_area_index ==MAX_SLOT_AREA ) { -debug_putstr ("Aborted e820 scan (slot_areas full)!\n" ); -break ; - } - } - +process_e820_entry (minimum, image_size);return slots_fetch_random (); }
Signature · 1 line
2.5.5
Re: [PATCH v2 1/2] x86/boot/KASLR: Adapt process_e820_entry for any type of memory entry
Quoted 6 lines · Baoquan He
Now function
process_e820_entryis only used to process e820 memory entries. Adapt it for any type of memory entry, not just for e820. Later we will use it to process efi mirror regions.So rename the old
process_e820_entrytoprocess_mem_region, and extract and wrap the e820 specific processing code intoprocess_e820_entry.
This mixes changing the structure internals (.addr vs .start) with changing the processing logic (adding a wrapper). I would prefer this was done in several stages to make review easier:
1) lift e820 walking into a new function process_e820_entries(), and move TYPE_RAM logic there.
2) switch process_e820_entry() from struct boot_e820_entry to struct mem_vector.
3) rename (and adjust comments!) of process_e820_entry() into process_mem_region().
-Kees
Quoted 120 lines
Signed-off-by Baoquan He <[email protected]>--- arch/x86/boot/compressed/kaslr.c | 60 ++++++++++++++++++++++------------------ 1 file changed, 33 insertions(+), 27 deletions(-)arch/x86/boot/compressed/kaslr.c +33
-28@@ -479,35 +479,31 @@ static unsigned long slots_fetch_random(void)return 0 ; } -static void process_e820_entry (struct boot_e820_entry *entry, +static void process_mem_region (struct mem_vector *entry,unsigned long minimum,unsigned long image_size) {struct mem_vector region, overlap;struct slot_area slot_area;unsigned long start_orig, end; -struct boot_e820_entry cur_entry; - -/* Skip non-RAM entries. */ -if (entry->type !=E820_TYPE_RAM ) -return ; +struct mem_vector cur_entry;/* On 32-bit, ignore entries entirely above our maximum. */ -if (IS_ENABLED (CONFIG_X86_32 ) && entry->addr >=KERNEL_IMAGE_SIZE ) +if (IS_ENABLED (CONFIG_X86_32 ) && entry->start >=KERNEL_IMAGE_SIZE )return ;/* Ignore entries entirely below our minimum. */ -if (entry->addr + entry->size < minimum) +if (entry->start + entry->size < minimum)return ;/* Ignore entries above memory limit */ - end =min (entry->size + entry->addr, mem_limit); -if (entry->addr >= end) + end =min (entry->size + entry->start, mem_limit); +if (entry->start >= end)return ; - cur_entry.addr = entry->addr; - cur_entry.size = end - entry->addr; + cur_entry.start = entry->start; + cur_entry.size = end - entry->start; - region.start = cur_entry.addr; + region.start = cur_entry.start; region.size = cur_entry.size;/* Give up if slot area array is full. */ @@ -522,7 +518,7 @@ static void process_e820_entry(struct boot_e820_entry *entry, region.start =ALIGN (region.start,CONFIG_PHYSICAL_ALIGN );/* Did we raise the address above this e820 region? */ -if (region.start > cur_entry.addr + cur_entry.size) +if (region.start > cur_entry.start + cur_entry.size)return ;/* Reduce size by any delta from the original address. */ @@ -562,12 +558,31 @@ static void process_e820_entry(struct boot_e820_entry *entry, } } -static unsigned long find_random_phys_addr (unsigned long minimum, -unsigned long image_size) +static void process_e820_entry (unsigned long minimum,unsigned long image_size) {int i; -unsigned long addr; +struct mem_vector region; +struct boot_e820_entry *entry; + +/* Verify potential e820 positions, appending to slots list. */ +for (i =0 ; i < boot_params->e820_entries; i++) { + entry = &boot_params->e820_table[i]; +/* Skip non-RAM entries. */ +if (entry->type !=E820_TYPE_RAM ) +continue ; + region.start = entry->addr; + region.size = entry->size; +process_mem_region (®ion, minimum, image_size); +if (slot_area_index ==MAX_SLOT_AREA ) { +debug_putstr ("Aborted e820 scan (slot_areas full)!\n" ); +break ; + } + } +} +static unsigned long find_random_phys_addr (unsigned long minimum, +unsigned long image_size) +{/* Check if we had too many memmaps. */ if (memmap_too_large) {debug_putstr ("Aborted e820 scan (more than 4 memmap= args)!\n" );@@ -577,16 +592,7 @@ static unsigned long find_random_phys_addr(unsigned long minimum,/* Make sure minimum is aligned. */ minimum =ALIGN (minimum,CONFIG_PHYSICAL_ALIGN ); -/* Verify potential e820 positions, appending to slots list. */ -for (i =0 ; i < boot_params->e820_entries; i++) { -process_e820_entry (&boot_params->e820_table[i], minimum, - image_size); -if (slot_area_index ==MAX_SLOT_AREA ) { -debug_putstr ("Aborted e820 scan (slot_areas full)!\n" ); -break ; - } - } - +process_e820_entry (minimum, image_size);return slots_fetch_random (); } --2.5.5
Signature · 2 lines
Kees Cook Pixel Security
Re: [PATCH v2 1/2] x86/boot/KASLR: Adapt process_e820_entry for any type of memory entry
Quoted 11 lines · Kees Cook
Quoted 6 lines · Baoquan He
Now function
process_e820_entryis only used to process e820 memory entries. Adapt it for any type of memory entry, not just for e820. Later we will use it to process efi mirror regions.So rename the old
process_e820_entrytoprocess_mem_region, and extract and wrap the e820 specific processing code intoprocess_e820_entry.This mixes changing the structure internals (.addr vs .start) with changing the processing logic (adding a wrapper). I would prefer this was done in several stages to make review easier:
OK, will do following below steps. Thanks!
Quoted 137 lines
1) lift e820 walking into a new function
process_e820_entries(), and moveTYPE_RAMlogic there.2) switch
process_e820_entry()from structboot_e820_entryto structmem_vector.3) rename (and adjust comments!) of
process_e820_entry()intoprocess_mem_region().-Kees
Quoted 120 lines
Signed-off-by Baoquan He <[email protected]>--- arch/x86/boot/compressed/kaslr.c | 60 ++++++++++++++++++++++------------------ 1 file changed, 33 insertions(+), 27 deletions(-)arch/x86/boot/compressed/kaslr.c +33
-28@@ -479,35 +479,31 @@ static unsigned long slots_fetch_random(void)return 0 ; } -static void process_e820_entry (struct boot_e820_entry *entry, +static void process_mem_region (struct mem_vector *entry,unsigned long minimum,unsigned long image_size) {struct mem_vector region, overlap;struct slot_area slot_area;unsigned long start_orig, end; -struct boot_e820_entry cur_entry; - -/* Skip non-RAM entries. */ -if (entry->type !=E820_TYPE_RAM ) -return ; +struct mem_vector cur_entry;/* On 32-bit, ignore entries entirely above our maximum. */ -if (IS_ENABLED (CONFIG_X86_32 ) && entry->addr >=KERNEL_IMAGE_SIZE ) +if (IS_ENABLED (CONFIG_X86_32 ) && entry->start >=KERNEL_IMAGE_SIZE )return ;/* Ignore entries entirely below our minimum. */ -if (entry->addr + entry->size < minimum) +if (entry->start + entry->size < minimum)return ;/* Ignore entries above memory limit */ - end =min (entry->size + entry->addr, mem_limit); -if (entry->addr >= end) + end =min (entry->size + entry->start, mem_limit); +if (entry->start >= end)return ; - cur_entry.addr = entry->addr; - cur_entry.size = end - entry->addr; + cur_entry.start = entry->start; + cur_entry.size = end - entry->start; - region.start = cur_entry.addr; + region.start = cur_entry.start; region.size = cur_entry.size;/* Give up if slot area array is full. */ @@ -522,7 +518,7 @@ static void process_e820_entry(struct boot_e820_entry *entry, region.start =ALIGN (region.start,CONFIG_PHYSICAL_ALIGN );/* Did we raise the address above this e820 region? */ -if (region.start > cur_entry.addr + cur_entry.size) +if (region.start > cur_entry.start + cur_entry.size)return ;/* Reduce size by any delta from the original address. */ @@ -562,12 +558,31 @@ static void process_e820_entry(struct boot_e820_entry *entry, } } -static unsigned long find_random_phys_addr (unsigned long minimum, -unsigned long image_size) +static void process_e820_entry (unsigned long minimum,unsigned long image_size) {int i; -unsigned long addr; +struct mem_vector region; +struct boot_e820_entry *entry; + +/* Verify potential e820 positions, appending to slots list. */ +for (i =0 ; i < boot_params->e820_entries; i++) { + entry = &boot_params->e820_table[i]; +/* Skip non-RAM entries. */ +if (entry->type !=E820_TYPE_RAM ) +continue ; + region.start = entry->addr; + region.size = entry->size; +process_mem_region (®ion, minimum, image_size); +if (slot_area_index ==MAX_SLOT_AREA ) { +debug_putstr ("Aborted e820 scan (slot_areas full)!\n" ); +break ; + } + } +} +static unsigned long find_random_phys_addr (unsigned long minimum, +unsigned long image_size) +{/* Check if we had too many memmaps. */ if (memmap_too_large) {debug_putstr ("Aborted e820 scan (more than 4 memmap= args)!\n" );@@ -577,16 +592,7 @@ static unsigned long find_random_phys_addr(unsigned long minimum,/* Make sure minimum is aligned. */ minimum =ALIGN (minimum,CONFIG_PHYSICAL_ALIGN ); -/* Verify potential e820 positions, appending to slots list. */ -for (i =0 ; i < boot_params->e820_entries; i++) { -process_e820_entry (&boot_params->e820_table[i], minimum, - image_size); -if (slot_area_index ==MAX_SLOT_AREA ) { -debug_putstr ("Aborted e820 scan (slot_areas full)!\n" ); -break ; - } - } - +process_e820_entry (minimum, image_size);return slots_fetch_random (); } --2.5.5
Signature · 2 lines
Kees Cook Pixel Security
PATCH v2 2/2 x86/boot/KASLR: Restrict kernel to be randomized in mirror regions
In reply to Baoquan HeKernel text may be located in non-mirror regions (movable zone) when both address range mirroring feature and KASLR are enabled.
The address range mirroring feature arranges such mirror region into normal zone and other region into movable zone in order to locate kernel code and data in mirror region. The physical memory region whose descriptors in EFI memory map has EFI_MEMORY_MORE_RELIABLE attribute (bit: 16) are mirrored.
If efi is detected, iterate efi memory map and pick the mirror region to process for adding candidate of randomization slot. If efi is disabled or no mirror region found, still process e820 memory map.
--- arch/x86/boot/compressed/kaslr.c | 52 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 51 insertions(+), 1 deletion(-)
arch/x86/boot/compressed/kaslr.c +51 -1
@@ -37,7 +37,9 @@#include <linux/uts.h> #include <linux/utsname.h> #include <linux/ctype.h> +#include <linux/efi.h> #include <generated/utsrelease.h> +#include <asm/efi.h> /* Macros used by the included decompressor code below. */ #define STATIC
@@ -558,6 +560,50 @@ static void process_mem_region(struct mem_vector *entry, } } +/* Marks if efi mirror regions have been found and handled. */ +static bool efi_mirror_found; + +static void process_efi_entry (unsigned long minimum,unsigned long image_size) +{ +struct efi_info *e = &boot_params->efi_info; +struct mem_vector region; +efi_memory_desc_t *md; +unsigned long pmap; +char *signature; +u32 nr_desc; +int i; + + +#ifdef CONFIG_EFI + signature = (char *)&boot_params->efi_info.efi_loader_signature; +#endif +if (strncmp (signature,EFI32_LOADER_SIGNATURE ,4 ) && +strncmp (signature,EFI64_LOADER_SIGNATURE ,4 )) +return ; + +#ifdef CONFIG_X86_32 +/* Can't handle data above 4GB at this time */ +if (e->efi_memmap_hi) { +warn ("Memory map is above 4GB, EFI should be disabled.\n" ); +return ; + } + pmap = e->efi_memmap; +#else + pmap = (e->efi_memmap | ((__u64 )e->efi_memmap_hi <<32 )); +#endif + + nr_desc = e->efi_memmap_size / e->efi_memdesc_size; +for (i =0 ; i < nr_desc; i++) { + md = (efi_memory_desc_t *)(pmap + (i * e->efi_memdesc_size)); +if (md->attribute &EFI_MEMORY_MORE_RELIABLE ) { + region.start = md->phys_addr; + region.size = md->num_pages <<EFI_PAGE_SHIFT ; +process_mem_region (®ion, minimum, image_size); + efi_mirror_found = true; + } + } +} +static void process_e820_entry (unsigned long minimum,unsigned long image_size) {int i;
@@ -592,6 +638,10 @@ static unsigned long find_random_phys_addr(unsigned long minimum,/* Make sure minimum is aligned. */ minimum =ALIGN (minimum,CONFIG_PHYSICAL_ALIGN ); +process_efi_entry (minimum, image_size); +if (efi_mirror_found) +return slots_fetch_random (); +process_e820_entry (minimum, image_size);return slots_fetch_random (); }
@@ -651,7 +701,7 @@ void choose_random_location(unsigned long input,*/ min_addr =min (*output,512UL <<20 ); -/* Walk e820 and find a random address. */ +/* Walk available memory entries to find a random address. */ random_addr =find_random_phys_addr (min_addr, output_size);if (!random_addr) {warn ("Physical KASLR disabled: no suitable memory region!" );
Signature · 1 line
2.5.5
Quoted 7 lines · Baoquan He
arch/x86/boot/compressed/kaslr.c +7
-0+/* Marks if efi mirror regions have been found and handled. */ +static bool efi_mirror_found; + +static void process_efi_entry (unsigned long minimum,unsigned long image_size) +{ +struct efi_info *e = &boot_params->efi_info; +struct mem_vector region;
arch/x86/boot/compressed/kaslr.c static void process_mem_region(struct mem_vector *entry, · line 579
Quoted 10 lines
arch/x86/boot/compressed/kaslr.c +10
-0+efi_memory_desc_t *md; +unsigned long pmap; +char *signature; +u32 nr_desc; +int i; + + +#ifdef CONFIG_EFI + signature = (char *)&boot_params->efi_info.efi_loader_signature; +#endif
So if CONFIG_EFI=n you happily dereference the uninitialized signature pointer ...
Why is process_efi_entry() invoked at all if EFI is not enabled?
arch/x86/boot/compressed/kaslr.c static void process_mem_region(struct mem_vector *entry, · line 583
Quoted 4 lines
arch/x86/boot/compressed/kaslr.c +4
-0+if (strncmp (signature,EFI32_LOADER_SIGNATURE ,4 ) && +strncmp (signature,EFI64_LOADER_SIGNATURE ,4 )) +return ; +
Thanks,
tglx
Quoted 13 lines · Thomas Gleixner
Quoted 12 lines · Baoquan He
arch/x86/boot/compressed/kaslr.c +12
-0+/* Marks if efi mirror regions have been found and handled. */ +static bool efi_mirror_found; + +static void process_efi_entry (unsigned long minimum,unsigned long image_size) +{ +struct efi_info *e = &boot_params->efi_info; +struct mem_vector region; +efi_memory_desc_t *md; +unsigned long pmap; +char *signature; +u32 nr_desc; +int i;
Quoted 8 lines
arch/x86/boot/compressed/kaslr.c static void process_mem_region(struct mem_vector *entry, · line 579
Quoted 5 lines
arch/x86/boot/compressed/kaslr.c +5
-0+ + +#ifdef CONFIG_EFI + signature = (char *)&boot_params->efi_info.efi_loader_signature; +#endif So if
CONFIG_EFI=nyou happily dereference the uninitialized signature pointer ...
Right, this is a mistake. Thanks for pointing it out. I should have checked if the pointer is NULL.
In fact I just referred to code in setup_arch(). Now I have a question, though CONFIG_EFI=y but efi firmware is not enabled, boot_params.efi_info.efi_loader_signature should be initilized to 0. Then below code is also problematic.
#ifdef CONFIG_EFI
if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
EFI32_LOADER_SIGNATURE, 4)) {
set_bit(EFI_BOOT, &efi.flags);
} else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
EFI64_LOADER_SIGNATURE, 4)) {
set_bit(EFI_BOOT, &efi.flags);
set_bit(EFI_64BIT, &efi.flags);
}
if (efi_enabled(EFI_BOOT))
efi_memblock_x86_reserve_range();#endif
Quoted 2 lines
Why is
process_efi_entry()invoked at all if EFI is not enabled?
Yeah, and it's better to check if CONFIG_EFI is enabled before invocation of process_efi_entry(). Let me change it as below and repost. Thanks again for looking into this patchset.
+#ifdef CONFIG_EFI
process_efi_entry(minimum, image_size);
+#endif
Quoted 9 lines
arch/x86/boot/compressed/kaslr.c static void process_mem_region(struct mem_vector *entry, · line 583
Quoted 5 lines
arch/x86/boot/compressed/kaslr.c +4
-0+if (strncmp (signature,EFI32_LOADER_SIGNATURE ,4 ) && +strncmp (signature,EFI64_LOADER_SIGNATURE ,4 )) +return ; +Thanks,
tglx
Quoted 23 lines · Baoquan He
Quoted 13 lines · Thomas Gleixner
Quoted 12 lines · Baoquan He
arch/x86/boot/compressed/kaslr.c +12
-0+/* Marks if efi mirror regions have been found and handled. */ +static bool efi_mirror_found; + +static void process_efi_entry (unsigned long minimum,unsigned long image_size) +{ +struct efi_info *e = &boot_params->efi_info; +struct mem_vector region; +efi_memory_desc_t *md; +unsigned long pmap; +char *signature; +u32 nr_desc; +int i;Quoted 8 lines
arch/x86/boot/compressed/kaslr.c static void process_mem_region(struct mem_vector *entry, · line 579
Quoted 5 lines
arch/x86/boot/compressed/kaslr.c +5
-0+ + +#ifdef CONFIG_EFI + signature = (char *)&boot_params->efi_info.efi_loader_signature; +#endif So if
CONFIG_EFI=nyou happily dereference the uninitialized signature pointer ...
Quoted 2 lines
Right, this is a mistake. Thanks for pointing it out. I should have checked if the pointer is NULL.
The pointer is not NULL, it's not initialized.
Quoted 17 lines
In fact I just referred to code in
setup_arch(). Now I have a question, thoughCONFIG_EFI=ybut efi firmware is not enabled, boot_params.efi_info.efi_loader_signature should be initilized to 0. Then below code is also problematic.#ifdef CONFIG_EFI if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, EFI32_LOADER_SIGNATURE, 4)) { set_bit(EFI_BOOT, &efi.flags); } else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, EFI64_LOADER_SIGNATURE, 4)) { set_bit(EFI_BOOT, &efi.flags); set_bit(EFI_64BIT, &efi.flags); } if (efi_enabled(EFI_BOOT)) efi_memblock_x86_reserve_range();
Quoted 1 line
#endif
Indeed. Matt?
Thanks,
tglx
Quoted 17 lines · Thomas Gleixner
Quoted 15 lines · Baoquan He
In fact I just referred to code in
setup_arch(). Now I have a question, thoughCONFIG_EFI=ybut efi firmware is not enabled, boot_params.efi_info.efi_loader_signature should be initilized to 0. Then below code is also problematic.#ifdef CONFIG_EFI if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, EFI32_LOADER_SIGNATURE, 4)) { set_bit(EFI_BOOT, &efi.flags); } else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, EFI64_LOADER_SIGNATURE, 4)) { set_bit(EFI_BOOT, &efi.flags); set_bit(EFI_64BIT, &efi.flags); }
Quoted 5 lines
Quoted 3 lines
if (efi_enabled(EFI_BOOT)) efi_memblock_x86_reserve_range();#endif
Indeed. Matt?
It's possibly that I'm missing some context, but boot_params should be zero'd -- the x86 boot protocol requires that the entire data structure be zero'd on allocation.
Have I missed something?
Quoted 22 lines · Matt Fleming
Quoted 21 lines · Thomas Gleixner
Quoted 18 lines · Baoquan He
In fact I just referred to code in
setup_arch(). Now I have a question, thoughCONFIG_EFI=ybut efi firmware is not enabled, boot_params.efi_info.efi_loader_signature should be initilized to 0. Then below code is also problematic.#ifdef CONFIG_EFI if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, EFI32_LOADER_SIGNATURE, 4)) { set_bit(EFI_BOOT, &efi.flags); } else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, EFI64_LOADER_SIGNATURE, 4)) { set_bit(EFI_BOOT, &efi.flags); set_bit(EFI_64BIT, &efi.flags); } if (efi_enabled(EFI_BOOT)) efi_memblock_x86_reserve_range();#endif
Quoted 7 lines
Quoted 1 line
Indeed. Matt?
It's possibly that I'm missing some context, but
boot_paramsshould be zero'd -- the x86 boot protocol requires that the entire data structure be zero'd on allocation.Have I missed something?
No. I misread the code. The strncmp() operates on boot_params.efi_info.efi_loader_signature itself, so yes, all is fine.
It's just Baoquans copy and paste wreckage which is busted.
Thanks,
tglx
Quoted 25 lines · Thomas Gleixner
Quoted 24 lines · Matt Fleming
Quoted 22 lines · Thomas Gleixner
Quoted 17 lines · Baoquan He
In fact I just referred to code in
setup_arch(). Now I have a question, thoughCONFIG_EFI=ybut efi firmware is not enabled, boot_params.efi_info.efi_loader_signature should be initilized to 0. Then below code is also problematic.#ifdef CONFIG_EFI if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, EFI32_LOADER_SIGNATURE, 4)) { set_bit(EFI_BOOT, &efi.flags); } else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature, EFI64_LOADER_SIGNATURE, 4)) { set_bit(EFI_BOOT, &efi.flags); set_bit(EFI_64BIT, &efi.flags); } if (efi_enabled(EFI_BOOT)) efi_memblock_x86_reserve_range();Quoted 1 line
#endif
Indeed. Matt?
Quoted 8 lines
Quoted 5 lines
It's possibly that I'm missing some context, but
boot_paramsshould be zero'd -- the x86 boot protocol requires that the entire data structure be zero'd on allocation.Have I missed something?
No. I misread the code. The
strncmp()operates on boot_params.efi_info.efi_loader_signature itself, so yes, all is fine.
Sorry, I must be dizzy at late night of yesterday, just gave wrong answer when questioned.
Quoted 7 lines
It's just Baoquans copy and paste wreckage which is busted.
Thanks,
tglx