diff options
author | Al Viro <viro@ZenIV.linux.org.uk> | 2008-01-02 14:09:57 +0000 |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2008-01-02 13:13:27 -0800 |
commit | 831830b5a2b5d413407adf380ef62fe17d6fcbf2 (patch) | |
tree | b08f54f15374b5b98b0b3bea20a1d2ea8d1f50e0 /fs/proc/task_mmu.c | |
parent | ac40532ef0b8649e6f7f83859ea0de1c4ed08a19 (diff) | |
download | op-kernel-dev-831830b5a2b5d413407adf380ef62fe17d6fcbf2.zip op-kernel-dev-831830b5a2b5d413407adf380ef62fe17d6fcbf2.tar.gz |
restrict reading from /proc/<pid>/maps to those who share ->mm or can ptrace pid
Contents of /proc/*/maps is sensitive and may become sensitive after
open() (e.g. if target originally shares our ->mm and later does exec
on suid-root binary).
Check at read() (actually, ->start() of iterator) time that mm_struct
we'd grabbed and locked is
- still the ->mm of target
- equal to reader's ->mm or the target is ptracable by reader.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/proc/task_mmu.c')
-rw-r--r-- | fs/proc/task_mmu.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index c24d81a..8043a3e 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -397,12 +397,11 @@ static void *m_start(struct seq_file *m, loff_t *pos) if (!priv->task) return NULL; - mm = get_task_mm(priv->task); + mm = mm_for_maps(priv->task); if (!mm) return NULL; priv->tail_vma = tail_vma = get_gate_vma(priv->task); - down_read(&mm->mmap_sem); /* Start with last addr hint */ if (last_addr && (vma = find_vma(mm, last_addr))) { |