| Message ID | 20170702192452.GA11868@p100.box (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
diff --git a/mm/mmap.c b/mm/mmap.c index a5e3dcd..cc2fc8a 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2232,7 +2232,7 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address) /* Guard against exceeding limits of the address space. */ address &= PAGE_MASK; - if (address >= TASK_SIZE) + if (address >= (TASK_SIZE & PAGE_MASK)) return -ENOMEM; address += PAGE_SIZE;
Jörn Engel noticed that the expand_upwards() function might not return -ENOMEM in case the requested address is (unsigned long)-PAGE_SIZE and if the architecture didn't defined TASK_SIZE as multiple of PAGE_SIZE. Affected architectures are arm, frv, m68k, blackfin, h8300 and xtensa which all define TASK_SIZE as 0xffffffff, but since none of those have an upwards-growing stack we currently have no actual issue. Nevertheless let's fix this just in case any of the architectures with an upward-growing stack (currently parisc, metag and partly ia64) define TASK_SIZE similar. Reported-by: Jörn Engel <joern@purestorage.com> Fixes: bd726c90b6b8 ("Allow stack to grow up to address space limit") Cc: stable@vger.kernel.org Signed-off-by: Helge Deller <deller@gmx.de> -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html