diff options
author | Alexandre Ghiti <alex@ghiti.fr> | 2019-09-24 00:38:57 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-25 00:54:11 +0200 |
commit | 86e568e9c0525fc40e76d827212d5e9721cf7504 (patch) | |
tree | 204e2e88f6e2cf97e2db50274b2980d7f491aefa /arch/arm | |
parent | arm: properly account for stack randomization and stack guard gap (diff) | |
download | linux-86e568e9c0525fc40e76d827212d5e9721cf7504.tar.xz linux-86e568e9c0525fc40e76d827212d5e9721cf7504.zip |
arm: use STACK_TOP when computing mmap base address
mmap base address must be computed wrt stack top address, using TASK_SIZE
is wrong since STACK_TOP and TASK_SIZE are not equivalent.
Link: http://lkml.kernel.org/r/20190730055113.23635-8-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Hogan <jhogan@kernel.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/arm')
-rw-r--r-- | arch/arm/mm/mmap.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c index bff3d00bda5b..0b94b674aa91 100644 --- a/arch/arm/mm/mmap.c +++ b/arch/arm/mm/mmap.c @@ -19,7 +19,7 @@ /* gap between mmap and stack */ #define MIN_GAP (128*1024*1024UL) -#define MAX_GAP ((TASK_SIZE)/6*5) +#define MAX_GAP ((STACK_TOP)/6*5) #define STACK_RND_MASK (0x7ff >> (PAGE_SHIFT - 12)) static int mmap_is_legacy(struct rlimit *rlim_stack) @@ -51,7 +51,7 @@ static unsigned long mmap_base(unsigned long rnd, struct rlimit *rlim_stack) else if (gap > MAX_GAP) gap = MAX_GAP; - return PAGE_ALIGN(TASK_SIZE - gap - rnd); + return PAGE_ALIGN(STACK_TOP - gap - rnd); } /* |