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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-09-11 19:18:28 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-09-11 19:18:28 +0100 |
| commit | c2172ce2303051764829d4958bd50a11ada0590f (patch) | |
| tree | c465594496072249d2ad8ee4642f7c5dcd57e139 /arch/arm/xen | |
| parent | a4a5a7379e4ca03c192b732d61e446994eb67bbc (diff) | |
| parent | 0b61f2c0f37983c98ed4207f3f5e265938371b68 (diff) | |
| download | linux-c2172ce2303051764829d4958bd50a11ada0590f.tar.gz linux-c2172ce2303051764829d4958bd50a11ada0590f.tar.xz | |
Merge branch 'uaccess' into fixes
Diffstat (limited to 'arch/arm/xen')
| -rw-r--r-- | arch/arm/xen/hypercall.S | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/arm/xen/hypercall.S b/arch/arm/xen/hypercall.S index f00e08075938..10fd99c568c6 100644 --- a/arch/arm/xen/hypercall.S +++ b/arch/arm/xen/hypercall.S @@ -98,8 +98,23 @@ ENTRY(privcmd_call) mov r1, r2 mov r2, r3 ldr r3, [sp, #8] + /* + * Privcmd calls are issued by the userspace. We need to allow the + * kernel to access the userspace memory before issuing the hypercall. + */ + uaccess_enable r4 + + /* r4 is loaded now as we use it as scratch register before */ ldr r4, [sp, #4] __HVC(XEN_IMM) + + /* + * Disable userspace access from kernel. This is fine to do it + * unconditionally as no set_fs(KERNEL_DS)/set_fs(get_ds()) is + * called before. + */ + uaccess_disable r4 + ldm sp!, {r4} ret lr ENDPROC(privcmd_call); |