From 18ccb0cab49ef7868eaf9504f257e1a84683dbbd Mon Sep 17 00:00:00 2001 From: Andreas Schwab Date: Mon, 16 Mar 2015 16:32:22 +0000 Subject: arm64: fix implementation of mmap2 compat syscall The arm mmap2 syscall takes the offset in units of 4K, thus with 64K pages the offset needs to be scaled to units of pages. Signed-off-by: Andreas Schwab Signed-off-by: Alexander Graf [will: removed redundant lr parameter, localised PAGE_SHIFT #if check] Signed-off-by: Will Deacon --- arch/arm64/kernel/entry32.S | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'arch/arm64/kernel/entry32.S') diff --git a/arch/arm64/kernel/entry32.S b/arch/arm64/kernel/entry32.S index 9a8f6ae2530e..bd9bfaa9269b 100644 --- a/arch/arm64/kernel/entry32.S +++ b/arch/arm64/kernel/entry32.S @@ -19,9 +19,12 @@ */ #include +#include #include #include +#include +#include /* * System call wrappers for the AArch32 compatibility layer. @@ -53,6 +56,21 @@ ENTRY(compat_sys_fstatfs64_wrapper) b compat_sys_fstatfs64 ENDPROC(compat_sys_fstatfs64_wrapper) +/* + * Note: off_4k (w5) is always in units of 4K. If we can't do the + * requested offset because it is not page-aligned, we return -EINVAL. + */ +ENTRY(compat_sys_mmap2_wrapper) +#if PAGE_SHIFT > 12 + tst w5, #~PAGE_MASK >> 12 + b.ne 1f + lsr w5, w5, #PAGE_SHIFT - 12 +#endif + b sys_mmap_pgoff +1: mov x0, #-EINVAL + ret +ENDPROC(compat_sys_mmap2_wrapper) + /* * Wrappers for AArch32 syscalls that either take 64-bit parameters * in registers or that take 32-bit parameters which require sign -- cgit