4.19-stable review patch. If anyone has any objections, please let me know.
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Commit e3aa6243434fd9a82e84bb79ab1abd14f2d9a5a7 upstream.
When Spectre mitigation is required, __put_user() needs to include check_uaccess. This is already the case for put_user(), so just make __put_user() an alias of put_user().
Signed-off-by: Julien Thierry julien.thierry@arm.com Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: David A. Long dave.long@linaro.org Reviewed-by: Julien Thierry julien.thierry@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm/include/asm/uaccess.h | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-)
diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index d65ef85fc617..1191e7da8fab 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -370,6 +370,14 @@ do { \ __pu_err; \ })
+#ifdef CONFIG_CPU_SPECTRE +/* + * When mitigating Spectre variant 1.1, all accessors need to include + * verification of the address space. + */ +#define __put_user(x, ptr) put_user(x, ptr) + +#else #define __put_user(x, ptr) \ ({ \ long __pu_err = 0; \ @@ -377,12 +385,6 @@ do { \ __pu_err; \ })
-#define __put_user_error(x, ptr, err) \ -({ \ - __put_user_switch((x), (ptr), (err), __put_user_nocheck); \ - (void) 0; \ -}) - #define __put_user_nocheck(x, __pu_ptr, __err, __size) \ do { \ unsigned long __pu_addr = (unsigned long)__pu_ptr; \ @@ -462,6 +464,7 @@ do { \ : "r" (x), "i" (-EFAULT) \ : "cc")
+#endif /* !CONFIG_CPU_SPECTRE */
#ifdef CONFIG_MMU extern unsigned long __must_check