diff options
| author | Nick Piggin <npiggin@suse.de> | 2009-06-16 15:32:38 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-06-16 19:47:40 -0700 |
| commit | 75927af8bcb940dad4fe281713d526cb520869ff (patch) | |
| tree | 96b2b903ce215d3c47204b7b77724c9fa0aa6502 | |
| parent | dab48dab37d2770824420d1e01730a107fade1aa (diff) | |
| download | linux-75927af8bcb940dad4fe281713d526cb520869ff.tar.bz2 | |
mm: madvise(): correct return code
The posix_madvise() function succeeds (and does nothing) when called with
parameters (NULL, 0, -1); according to LSB tests, it should fail with
EINVAL because -1 is not a valid flag.
When called with a valid address and size, it correctly fails.
So perform an initial check for valid flags first.
Reported-by: Jiri Dluhos <jdluhos@novell.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Reviewed-and-Tested-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/madvise.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/mm/madvise.c b/mm/madvise.c index e994dcb479d6..76eb4193acdd 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -238,12 +238,30 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev, break; default: - error = -EINVAL; + BUG(); break; } return error; } +static int +madvise_behavior_valid(int behavior) +{ + switch (behavior) { + case MADV_DOFORK: + case MADV_DONTFORK: + case MADV_NORMAL: + case MADV_SEQUENTIAL: + case MADV_RANDOM: + case MADV_REMOVE: + case MADV_WILLNEED: + case MADV_DONTNEED: + return 1; + + default: + return 0; + } +} /* * The madvise(2) system call. * @@ -289,6 +307,9 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior) int write; size_t len; + if (!madvise_behavior_valid(behavior)) + return error; + write = madvise_need_mmap_write(behavior); if (write) down_write(¤t->mm->mmap_sem); |