diff options
Diffstat (limited to 'arch/s390/lib/uaccess.c')
| -rw-r--r-- | arch/s390/lib/uaccess.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/arch/s390/lib/uaccess.c b/arch/s390/lib/uaccess.c index fa7d98fa1320..1a6ba105e071 100644 --- a/arch/s390/lib/uaccess.c +++ b/arch/s390/lib/uaccess.c @@ -8,11 +8,13 @@ * Gerald Schaefer (gerald.schaefer@de.ibm.com) */ +#include <linux/kprobes.h> #include <linux/uaccess.h> #include <linux/export.h> #include <linux/mm.h> #include <asm/asm-extable.h> #include <asm/ctlreg.h> +#include <asm/skey.h> #ifdef CONFIG_DEBUG_ENTRY void debug_user_asce(int exit) @@ -145,3 +147,189 @@ unsigned long _copy_to_user_key(void __user *to, const void *from, return raw_copy_to_user_key(to, from, n, key); } EXPORT_SYMBOL(_copy_to_user_key); + +#define CMPXCHG_USER_KEY_MAX_LOOPS 128 + +static nokprobe_inline int __cmpxchg_user_key_small(unsigned long address, unsigned int *uval, + unsigned int old, unsigned int new, + unsigned int mask, unsigned long key) +{ + unsigned long count; + unsigned int prev; + bool sacf_flag; + int rc = 0; + + skey_regions_initialize(); + sacf_flag = enable_sacf_uaccess(); + asm_inline volatile( + "20: spka 0(%[key])\n" + " sacf 256\n" + " llill %[count],%[max_loops]\n" + "0: l %[prev],%[address]\n" + "1: nr %[prev],%[mask]\n" + " xilf %[mask],0xffffffff\n" + " or %[new],%[prev]\n" + " or %[prev],%[tmp]\n" + "2: lr %[tmp],%[prev]\n" + "3: cs %[prev],%[new],%[address]\n" + "4: jnl 5f\n" + " xr %[tmp],%[prev]\n" + " xr %[new],%[tmp]\n" + " nr %[tmp],%[mask]\n" + " jnz 5f\n" + " brct %[count],2b\n" + "5: sacf 768\n" + " spka %[default_key]\n" + "21:\n" + EX_TABLE_UA_LOAD_REG(0b, 5b, %[rc], %[prev]) + EX_TABLE_UA_LOAD_REG(1b, 5b, %[rc], %[prev]) + EX_TABLE_UA_LOAD_REG(3b, 5b, %[rc], %[prev]) + EX_TABLE_UA_LOAD_REG(4b, 5b, %[rc], %[prev]) + SKEY_REGION(20b, 21b) + : [rc] "+&d" (rc), + [prev] "=&d" (prev), + [address] "+Q" (*(int *)address), + [tmp] "+&d" (old), + [new] "+&d" (new), + [mask] "+&d" (mask), + [count] "=a" (count) + : [key] "%[count]" (key << 4), + [default_key] "J" (PAGE_DEFAULT_KEY), + [max_loops] "J" (CMPXCHG_USER_KEY_MAX_LOOPS) + : "memory", "cc"); + disable_sacf_uaccess(sacf_flag); + *uval = prev; + if (!count) + rc = -EAGAIN; + return rc; +} + +int __kprobes __cmpxchg_user_key1(unsigned long address, unsigned char *uval, + unsigned char old, unsigned char new, unsigned long key) +{ + unsigned int prev, shift, mask, _old, _new; + int rc; + + shift = (3 ^ (address & 3)) << 3; + address ^= address & 3; + _old = (unsigned int)old << shift; + _new = (unsigned int)new << shift; + mask = ~(0xff << shift); + rc = __cmpxchg_user_key_small(address, &prev, _old, _new, mask, key); + *uval = prev >> shift; + return rc; +} +EXPORT_SYMBOL(__cmpxchg_user_key1); + +int __kprobes __cmpxchg_user_key2(unsigned long address, unsigned short *uval, + unsigned short old, unsigned short new, unsigned long key) +{ + unsigned int prev, shift, mask, _old, _new; + int rc; + + shift = (2 ^ (address & 2)) << 3; + address ^= address & 2; + _old = (unsigned int)old << shift; + _new = (unsigned int)new << shift; + mask = ~(0xffff << shift); + rc = __cmpxchg_user_key_small(address, &prev, _old, _new, mask, key); + *uval = prev >> shift; + return rc; +} +EXPORT_SYMBOL(__cmpxchg_user_key2); + +int __kprobes __cmpxchg_user_key4(unsigned long address, unsigned int *uval, + unsigned int old, unsigned int new, unsigned long key) +{ + unsigned int prev = old; + bool sacf_flag; + int rc = 0; + + skey_regions_initialize(); + sacf_flag = enable_sacf_uaccess(); + asm_inline volatile( + "20: spka 0(%[key])\n" + " sacf 256\n" + "0: cs %[prev],%[new],%[address]\n" + "1: sacf 768\n" + " spka %[default_key]\n" + "21:\n" + EX_TABLE_UA_LOAD_REG(0b, 1b, %[rc], %[prev]) + EX_TABLE_UA_LOAD_REG(1b, 1b, %[rc], %[prev]) + SKEY_REGION(20b, 21b) + : [rc] "+&d" (rc), + [prev] "+&d" (prev), + [address] "+Q" (*(int *)address) + : [new] "d" (new), + [key] "a" (key << 4), + [default_key] "J" (PAGE_DEFAULT_KEY) + : "memory", "cc"); + disable_sacf_uaccess(sacf_flag); + *uval = prev; + return rc; +} +EXPORT_SYMBOL(__cmpxchg_user_key4); + +int __kprobes __cmpxchg_user_key8(unsigned long address, unsigned long *uval, + unsigned long old, unsigned long new, unsigned long key) +{ + unsigned long prev = old; + bool sacf_flag; + int rc = 0; + + skey_regions_initialize(); + sacf_flag = enable_sacf_uaccess(); + asm_inline volatile( + "20: spka 0(%[key])\n" + " sacf 256\n" + "0: csg %[prev],%[new],%[address]\n" + "1: sacf 768\n" + " spka %[default_key]\n" + "21:\n" + EX_TABLE_UA_LOAD_REG(0b, 1b, %[rc], %[prev]) + EX_TABLE_UA_LOAD_REG(1b, 1b, %[rc], %[prev]) + SKEY_REGION(20b, 21b) + : [rc] "+&d" (rc), + [prev] "+&d" (prev), + [address] "+QS" (*(long *)address) + : [new] "d" (new), + [key] "a" (key << 4), + [default_key] "J" (PAGE_DEFAULT_KEY) + : "memory", "cc"); + disable_sacf_uaccess(sacf_flag); + *uval = prev; + return rc; +} +EXPORT_SYMBOL(__cmpxchg_user_key8); + +int __kprobes __cmpxchg_user_key16(unsigned long address, __uint128_t *uval, + __uint128_t old, __uint128_t new, unsigned long key) +{ + __uint128_t prev = old; + bool sacf_flag; + int rc = 0; + + skey_regions_initialize(); + sacf_flag = enable_sacf_uaccess(); + asm_inline volatile( + "20: spka 0(%[key])\n" + " sacf 256\n" + "0: cdsg %[prev],%[new],%[address]\n" + "1: sacf 768\n" + " spka %[default_key]\n" + "21:\n" + EX_TABLE_UA_LOAD_REGPAIR(0b, 1b, %[rc], %[prev]) + EX_TABLE_UA_LOAD_REGPAIR(1b, 1b, %[rc], %[prev]) + SKEY_REGION(20b, 21b) + : [rc] "+&d" (rc), + [prev] "+&d" (prev), + [address] "+QS" (*(__int128_t *)address) + : [new] "d" (new), + [key] "a" (key << 4), + [default_key] "J" (PAGE_DEFAULT_KEY) + : "memory", "cc"); + disable_sacf_uaccess(sacf_flag); + *uval = prev; + return rc; +} +EXPORT_SYMBOL(__cmpxchg_user_key16); |