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| author | Gerald Schaefer <gerald.schaefer@de.ibm.com> | 2019-02-03 21:37:20 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2019-04-29 10:47:10 +0200 |
| commit | b2d24b97b2a9691351920e700bfda4368c177232 (patch) | |
| tree | afc715c3029b79cf1430781ffcbe39ff0656cadb /arch/s390/boot/ipl_parm.c | |
| parent | a80313ff91abda67641dc33bed97f6bcc5e9f6a4 (diff) | |
| download | linux-b2d24b97b2a9691351920e700bfda4368c177232.tar.bz2 | |
s390/kernel: add support for kernel address space layout randomization (KASLR)
This patch adds support for relocating the kernel to a random address.
The random kernel offset is obtained from cpacf, using either TRNG, PRNO,
or KMC_PRNG, depending on supported MSA level.
KERNELOFFSET is added to vmcoreinfo, for crash --kaslr support.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/boot/ipl_parm.c')
| -rw-r--r-- | arch/s390/boot/ipl_parm.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/arch/s390/boot/ipl_parm.c b/arch/s390/boot/ipl_parm.c index 96777092fb14..b49bd97d33af 100644 --- a/arch/s390/boot/ipl_parm.c +++ b/arch/s390/boot/ipl_parm.c @@ -18,6 +18,8 @@ unsigned long __bootdata(memory_end); int __bootdata(memory_end_set); int __bootdata(noexec_disabled); +int kaslr_enabled __section(.data); + static inline int __diag308(unsigned long subcode, void *addr) { register unsigned long _addr asm("0") = (unsigned long)addr; @@ -214,6 +216,7 @@ void parse_boot_command_line(void) char *args; int rc; + kaslr_enabled = IS_ENABLED(CONFIG_RANDOMIZE_BASE); args = strcpy(command_line_buf, early_command_line); while (*args) { args = next_arg(args, ¶m, &val); @@ -231,15 +234,21 @@ void parse_boot_command_line(void) if (!strcmp(param, "facilities")) modify_fac_list(val); + + if (!strcmp(param, "nokaslr")) + kaslr_enabled = 0; } } void setup_memory_end(void) { #ifdef CONFIG_CRASH_DUMP - if (!OLDMEM_BASE && ipl_block_valid && - ipl_block.pb0_hdr.pbt == IPL_PBT_FCP && - ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP) { + if (OLDMEM_BASE) { + kaslr_enabled = 0; + } else if (ipl_block_valid && + ipl_block.pb0_hdr.pbt == IPL_PBT_FCP && + ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP) { + kaslr_enabled = 0; if (!sclp_early_get_hsa_size(&memory_end) && memory_end) memory_end_set = 1; } |