From fa69c2b418d7aaae8d14810caecc9bfe3f44b4e5 Mon Sep 17 00:00:00 2001 From: Corey Wright Date: Sun, 28 Feb 2016 02:42:39 -0600 Subject: proc: Fix ptrace-based permission checks for accessing task maps Modify mm_access() calls in fs/proc/task_mmu.c and fs/proc/task_nommu.c to have the mode include PTRACE_MODE_FSCREDS so accessing /proc/pid/maps and /proc/pid/pagemap is not denied to all users. In backporting upstream commit caaee623 to pre-3.18 kernel versions it was overlooked that mm_access() is used in fs/proc/task_*mmu.c as those calls were removed in 3.18 (by upstream commit 29a40ace) and did not exist at the time of the original commit. Fixes: caaee6234d ("ptrace: use fsuid, fsgid, effective creds for fs access checks") Signed-off-by: Corey Wright Acked-by: Jann Horn Signed-off-by: Jiri Slaby --- fs/proc/task_mmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/proc/task_mmu.c') diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index d20f37d1c6e7..4fe8b1082cf3 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -172,7 +172,7 @@ static void *m_start(struct seq_file *m, loff_t *pos) if (!priv->task) return ERR_PTR(-ESRCH); - mm = mm_access(priv->task, PTRACE_MODE_READ); + mm = mm_access(priv->task, PTRACE_MODE_READ_FSCREDS); if (!mm || IS_ERR(mm)) return mm; down_read(&mm->mmap_sem); @@ -1186,7 +1186,7 @@ static ssize_t pagemap_read(struct file *file, char __user *buf, if (!pm.buffer) goto out_task; - mm = mm_access(task, PTRACE_MODE_READ); + mm = mm_access(task, PTRACE_MODE_READ_FSCREDS); ret = PTR_ERR(mm); if (!mm || IS_ERR(mm)) goto out_free; -- cgit v1.2.3