Re: [patch 2/4] mm: Use may_adjust_brk helper

From: Serge E. Hallyn
Date: Mon Aug 04 2014 - 16:25:54 EST


Quoting Cyrill Gorcunov (gorcunov@xxxxxxxxxx):
> Signed-off-by: Cyrill Gorcunov <gorcunov@xxxxxxxxxx>
> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> Cc: Tejun Heo <tj@xxxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Andrew Vagin <avagin@xxxxxxxxxx>
> Cc: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
> Cc: H. Peter Anvin <hpa@xxxxxxxxx>
> Cc: Serge Hallyn <serge.hallyn@xxxxxxxxxxxxx>

Acked-by: Serge Hallyn <serge.hallyn@xxxxxxxxxxxxx>

> Cc: Pavel Emelyanov <xemul@xxxxxxxxxxxxx>
> Cc: Vasiliy Kulikov <segoon@xxxxxxxxxxxx>
> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
> Cc: Michael Kerrisk <mtk.manpages@xxxxxxxxx>
> Cc: Julien Tinnes <jln@xxxxxxxxxx>
> ---
> kernel/sys.c | 11 ++++-------
> mm/mmap.c | 7 +++----
> 2 files changed, 7 insertions(+), 11 deletions(-)
>
> Index: linux-2.6.git/kernel/sys.c
> ===================================================================
> --- linux-2.6.git.orig/kernel/sys.c
> +++ linux-2.6.git/kernel/sys.c
> @@ -1693,7 +1693,6 @@ exit:
> static int prctl_set_mm(int opt, unsigned long addr,
> unsigned long arg4, unsigned long arg5)
> {
> - unsigned long rlim = rlimit(RLIMIT_DATA);
> struct mm_struct *mm = current->mm;
> struct vm_area_struct *vma;
> int error;
> @@ -1733,9 +1732,8 @@ static int prctl_set_mm(int opt, unsigne
> if (addr <= mm->end_data)
> goto out;
>
> - if (rlim < RLIM_INFINITY &&
> - (mm->brk - addr) +
> - (mm->end_data - mm->start_data) > rlim)
> + if (check_data_rlimit(rlimit(RLIMIT_DATA), mm->brk, addr,
> + mm->end_data, mm->start_data))
> goto out;
>
> mm->start_brk = addr;
> @@ -1745,9 +1743,8 @@ static int prctl_set_mm(int opt, unsigne
> if (addr <= mm->end_data)
> goto out;
>
> - if (rlim < RLIM_INFINITY &&
> - (addr - mm->start_brk) +
> - (mm->end_data - mm->start_data) > rlim)
> + if (check_data_rlimit(rlimit(RLIMIT_DATA), addr, mm->start_brk,
> + mm->end_data, mm->start_data))
> goto out;
>
> mm->brk = addr;
> Index: linux-2.6.git/mm/mmap.c
> ===================================================================
> --- linux-2.6.git.orig/mm/mmap.c
> +++ linux-2.6.git/mm/mmap.c
> @@ -263,7 +263,7 @@ static unsigned long do_brk(unsigned lon
>
> SYSCALL_DEFINE1(brk, unsigned long, brk)
> {
> - unsigned long rlim, retval;
> + unsigned long retval;
> unsigned long newbrk, oldbrk;
> struct mm_struct *mm = current->mm;
> unsigned long min_brk;
> @@ -293,9 +293,8 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
> * segment grow beyond its set limit the in case where the limit is
> * not page aligned -Ram Gupta
> */
> - rlim = rlimit(RLIMIT_DATA);
> - if (rlim < RLIM_INFINITY && (brk - mm->start_brk) +
> - (mm->end_data - mm->start_data) > rlim)
> + if (check_data_rlimit(rlimit(RLIMIT_DATA), brk, mm->start_brk,
> + mm->end_data, mm->start_data))
> goto out;
>
> newbrk = PAGE_ALIGN(brk);
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/