diff options
| author | Vasily Gorbik <gor@linux.ibm.com> | 2023-01-23 14:49:47 +0300 |
|---|---|---|
| committer | Heiko Carstens <hca@linux.ibm.com> | 2023-02-06 13:13:54 +0300 |
| commit | 22476f47b6b7fb7d066c71f67ebc11892adb0849 (patch) | |
| tree | e2a9ef86f38f3501764f5f8aed29d20fd40e29c4 /arch/s390/boot/kaslr.c | |
| parent | eb33f9eb304a4c18beb5ba6362eaa5c4beaf40d8 (diff) | |
| download | linux-22476f47b6b7fb7d066c71f67ebc11892adb0849.tar.xz | |
s390/boot: fix mem_detect extended area allocation
Allocation of mem_detect extended area was not considered neither
in commit 9641b8cc733f ("s390/ipl: read IPL report at early boot")
nor in commit b2d24b97b2a9 ("s390/kernel: add support for kernel address
space layout randomization (KASLR)"). As a result mem_detect extended
theoretically may overlap with ipl report or randomized kernel image
position. But as mem_detect code will allocate extended area only
upon exceeding 255 online regions (which should alternate with offline
memory regions) it is not seen in practice.
To make sure mem_detect extended area does not overlap with ipl report
or randomized kernel position extend usage of "safe_addr". Make initrd
handling and mem_detect extended area allocation code move it further
right and make KASLR takes in into consideration as well.
Fixes: 9641b8cc733f ("s390/ipl: read IPL report at early boot")
Fixes: b2d24b97b2a9 ("s390/kernel: add support for kernel address space layout randomization (KASLR)")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Diffstat (limited to 'arch/s390/boot/kaslr.c')
| -rw-r--r-- | arch/s390/boot/kaslr.c | 6 |
1 files changed, 0 insertions, 6 deletions
diff --git a/arch/s390/boot/kaslr.c b/arch/s390/boot/kaslr.c index e8d74d4f62aa..58a8d8c8a100 100644 --- a/arch/s390/boot/kaslr.c +++ b/arch/s390/boot/kaslr.c @@ -174,7 +174,6 @@ unsigned long get_random_base(unsigned long safe_addr) { unsigned long memory_limit = get_mem_detect_end(); unsigned long base_pos, max_pos, kernel_size; - unsigned long kasan_needs; int i; memory_limit = min(memory_limit, ident_map_size); @@ -186,12 +185,7 @@ unsigned long get_random_base(unsigned long safe_addr) */ memory_limit -= kasan_estimate_memory_needs(memory_limit); - if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && initrd_data.start && initrd_data.size) { - if (safe_addr < initrd_data.start + initrd_data.size) - safe_addr = initrd_data.start + initrd_data.size; - } safe_addr = ALIGN(safe_addr, THREAD_SIZE); - kernel_size = vmlinux.image_size + vmlinux.bss_size; if (safe_addr + kernel_size > memory_limit) return 0; |