From: Niels Dossche dossche.niels@gmail.com
commit 7d1e6496616275f3830e2f2f91fa69a66953e95b upstream.
The mremap syscall is supposed to return a pointer to the new virtual memory area on success, and a negative value of the error code in case of failure. Currently, EFAULT is returned when the VMA is not found, instead of -EFAULT. The users of this syscall will therefore believe the syscall succeeded in case the VMA didn't exist, as it returns a pointer to address 0xe (0xe being the value of EFAULT). Fix the sign of the error value.
Link: https://lkml.kernel.org/r/20220427224439.23828-2-dossche.niels@gmail.com Fixes: 550a7d60bd5e ("mm, hugepages: add mremap() support for hugepage backed vma") Signed-off-by: Niels Dossche dossche.niels@gmail.com Cc: Mina Almasry almasrymina@google.com Cc: Mike Kravetz mike.kravetz@oracle.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- mm/mremap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/mremap.c +++ b/mm/mremap.c @@ -947,7 +947,7 @@ SYSCALL_DEFINE5(mremap, unsigned long, a return -EINTR; vma = find_vma(mm, addr); if (!vma || vma->vm_start > addr) { - ret = EFAULT; + ret = -EFAULT; goto out; }