From: Niels Dossche <dossche.niels@xxxxxxxxx> 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@xxxxxxxxx Fixes: 550a7d60bd5e ("mm, hugepages: add mremap() support for hugepage backed vma") Signed-off-by: Niels Dossche <dossche.niels@xxxxxxxxx> Cc: Mina Almasry <almasrymina@xxxxxxxxxx> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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; }
