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authorLinus Torvalds <torvalds@linux-foundation.org>2020-10-22 09:59:21 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-10-22 09:59:21 -0700
commitf56e65dff6ad52395ef45738799b4fb70ff43376 (patch)
tree230e0ac39888f219a6859fb15ef548fb2bd6511c /arch/x86/lib/putuser.S
parent24717cfbbbbfa415d1e3dca0f21c417e5faf8208 (diff)
parent7b84b665c874f60d84547635341e418f20cbbab2 (diff)
Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull initial set_fs() removal from Al Viro: "Christoph's set_fs base series + fixups" * 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fs: Allow a NULL pos pointer to __kernel_read fs: Allow a NULL pos pointer to __kernel_write powerpc: remove address space overrides using set_fs() powerpc: use non-set_fs based maccess routines x86: remove address space overrides using set_fs() x86: make TASK_SIZE_MAX usable from assembly code x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32,64}_types.h lkdtm: remove set_fs-based tests test_bitmap: remove user bitmap tests uaccess: add infrastructure for kernel builds with set_fs() fs: don't allow splice read/write without explicit ops fs: don't allow kernel reads and writes without iter ops sysctl: Convert to iter interfaces proc: add a read_iter method to proc proc_ops proc: cleanup the compat vs no compat file ops proc: remove a level of indentation in proc_get_inode
Diffstat (limited to 'arch/x86/lib/putuser.S')
-rw-r--r--arch/x86/lib/putuser.S25
1 files changed, 13 insertions, 12 deletions
diff --git a/arch/x86/lib/putuser.S b/arch/x86/lib/putuser.S
index b34a17763f28..0ea344c5ea43 100644
--- a/arch/x86/lib/putuser.S
+++ b/arch/x86/lib/putuser.S
@@ -33,12 +33,19 @@
* as they get called from within inline assembly.
*/
-#define ENTER mov PER_CPU_VAR(current_task), %_ASM_BX
+#ifdef CONFIG_X86_5LEVEL
+#define LOAD_TASK_SIZE_MINUS_N(n) \
+ ALTERNATIVE __stringify(mov $((1 << 47) - 4096 - (n)),%rbx), \
+ __stringify(mov $((1 << 56) - 4096 - (n)),%rbx), X86_FEATURE_LA57
+#else
+#define LOAD_TASK_SIZE_MINUS_N(n) \
+ mov $(TASK_SIZE_MAX - (n)),%_ASM_BX
+#endif
.text
SYM_FUNC_START(__put_user_1)
- ENTER
- cmp TASK_addr_limit(%_ASM_BX),%_ASM_CX
+ LOAD_TASK_SIZE_MINUS_N(0)
+ cmp %_ASM_BX,%_ASM_CX
jae .Lbad_put_user
SYM_INNER_LABEL(__put_user_nocheck_1, SYM_L_GLOBAL)
ASM_STAC
@@ -51,9 +58,7 @@ EXPORT_SYMBOL(__put_user_1)
EXPORT_SYMBOL(__put_user_nocheck_1)
SYM_FUNC_START(__put_user_2)
- ENTER
- mov TASK_addr_limit(%_ASM_BX),%_ASM_BX
- sub $1,%_ASM_BX
+ LOAD_TASK_SIZE_MINUS_N(1)
cmp %_ASM_BX,%_ASM_CX
jae .Lbad_put_user
SYM_INNER_LABEL(__put_user_nocheck_2, SYM_L_GLOBAL)
@@ -67,9 +72,7 @@ EXPORT_SYMBOL(__put_user_2)
EXPORT_SYMBOL(__put_user_nocheck_2)
SYM_FUNC_START(__put_user_4)
- ENTER
- mov TASK_addr_limit(%_ASM_BX),%_ASM_BX
- sub $3,%_ASM_BX
+ LOAD_TASK_SIZE_MINUS_N(3)
cmp %_ASM_BX,%_ASM_CX
jae .Lbad_put_user
SYM_INNER_LABEL(__put_user_nocheck_4, SYM_L_GLOBAL)
@@ -83,9 +86,7 @@ EXPORT_SYMBOL(__put_user_4)
EXPORT_SYMBOL(__put_user_nocheck_4)
SYM_FUNC_START(__put_user_8)
- ENTER
- mov TASK_addr_limit(%_ASM_BX),%_ASM_BX
- sub $7,%_ASM_BX
+ LOAD_TASK_SIZE_MINUS_N(7)
cmp %_ASM_BX,%_ASM_CX
jae .Lbad_put_user
SYM_INNER_LABEL(__put_user_nocheck_8, SYM_L_GLOBAL)