From 569d1423ac2b585b5cb38bee545b5e0ae2bd7f67 Mon Sep 17 00:00:00 2001 From: James Hogan <james.hogan@imgtec.com> Date: Thu, 17 May 2012 12:42:54 +0100 Subject: [PATCH] mmap()->sys_mmap2: do unsigned shift of offset Fix the implementation of mmap based on the mmap2 system call, to construct pgoffset from offset with an unsigned shift rather than a signed (off_t) shift. The mmap2 test in the testsuite catches this case by mmap'ing with a large offset (with the sign bit set). The signed shift repeats the sign bit making the page shift way out of range. This is already fixed similarly in mmap64(). Signed-off-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> --- libc/sysdeps/linux/common/mmap.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libc/sysdeps/linux/common/mmap.c b/libc/sysdeps/linux/common/mmap.c index 8995898..d53eabb 100644 --- a/libc/sysdeps/linux/common/mmap.c +++ b/libc/sysdeps/linux/common/mmap.c @@ -63,7 +63,8 @@ __ptr_t mmap(__ptr_t addr, size_t len, int prot, int flags, int fd, __off_t offs __set_errno(EINVAL); return MAP_FAILED; } - return __syscall_mmap2(addr, len, prot, flags, fd, offset >> MMAP2_PAGE_SHIFT); + return __syscall_mmap2(addr, len, prot, flags, + fd, ((__u_long) offset >> MMAP2_PAGE_SHIFT)); } libc_hidden_def(mmap) -- 1.7.10.4