The patch titled Subject: mm: pagemap_read: limit scan to virtual region being asked has been removed from the -mm tree. Its filename was mm-pagemap-limit-scan-to-virtual-region-being-asked.patch This patch was dropped because it is obsolete ------------------------------------------------------ From: Shiraz Hashim <shashim@xxxxxxxxxxxxxx> Subject: mm: pagemap_read: limit scan to virtual region being asked pagemap_read scans through the virtual address space of a task until it prepares 'count' pagemaps or it reaches end of task. This presents a problem when the page walk doesn't happen for a vma with VM_PFNMAP set. In this case the walk is silently skipped and no pagemap is prepared, in turn making pagemap_read scan through to task end, even crossing beyond 'count', landing into a different vma region. This leads to wrong presentation of mappings for that vma. Fix this by limiting end_vaddr to the end of the virtual address region being scanned. Signed-off-by: Shiraz Hashim <shashim@xxxxxxxxxxxxxx> Cc: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Cyrill Gorcunov <gorcunov@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/proc/task_mmu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff -puN fs/proc/task_mmu.c~mm-pagemap-limit-scan-to-virtual-region-being-asked fs/proc/task_mmu.c --- a/fs/proc/task_mmu.c~mm-pagemap-limit-scan-to-virtual-region-being-asked +++ a/fs/proc/task_mmu.c @@ -1259,7 +1259,9 @@ static ssize_t pagemap_read(struct file src = *ppos; svpfn = src / PM_ENTRY_BYTES; start_vaddr = svpfn << PAGE_SHIFT; - end_vaddr = TASK_SIZE_OF(task); + end_vaddr = start_vaddr + ((count / PM_ENTRY_BYTES) << PAGE_SHIFT); + if ((end_vaddr > TASK_SIZE_OF(task)) || (end_vaddr < start_vaddr)) + end_vaddr = TASK_SIZE_OF(task); /* watch out for wraparound */ if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT) _ Patches currently in -mm which might be from shashim@xxxxxxxxxxxxxx are origin.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html