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| author | SeongJae Park <sj@kernel.org> | 2021-11-20 03:43:49 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-11-25 11:48:43 +0300 |
| commit | cda10b34ecfb27935f4a4dad0d0cb1f6405747b4 (patch) | |
| tree | 7c7f8ce21f765459be1b23758e06efad9b00b7fd /mm/damon | |
| parent | 4dfddb52abc205fa86c9528ed5eadce7da5abcba (diff) | |
| download | linux-cda10b34ecfb27935f4a4dad0d0cb1f6405747b4.tar.xz | |
mm/damon/dbgfs: use '__GFP_NOWARN' for user-specified size buffer allocation
commit db7a347b26fe05d2e8c115bb24dfd908d0252bc3 upstream.
Patch series "DAMON fixes".
This patch (of 2):
DAMON users can trigger below warning in '__alloc_pages()' by invoking
write() to some DAMON debugfs files with arbitrarily high count
argument, because DAMON debugfs interface allocates some buffers based
on the user-specified 'count'.
if (unlikely(order >= MAX_ORDER)) {
WARN_ON_ONCE(!(gfp & __GFP_NOWARN));
return NULL;
}
Because the DAMON debugfs interface code checks failure of the
'kmalloc()', this commit simply suppresses the warnings by adding
'__GFP_NOWARN' flag.
Link: https://lkml.kernel.org/r/20211110145758.16558-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20211110145758.16558-2-sj@kernel.org
Fixes: 4bc05954d007 ("mm/damon: implement a debugfs-based user space interface")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm/damon')
| -rw-r--r-- | mm/damon/dbgfs.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index faee070977d8..2741ff79e8e8 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -32,7 +32,7 @@ static char *user_input_str(const char __user *buf, size_t count, loff_t *ppos) if (*ppos) return ERR_PTR(-EINVAL); - kbuf = kmalloc(count + 1, GFP_KERNEL); + kbuf = kmalloc(count + 1, GFP_KERNEL | __GFP_NOWARN); if (!kbuf) return ERR_PTR(-ENOMEM); @@ -247,7 +247,7 @@ static ssize_t dbgfs_kdamond_pid_read(struct file *file, char *kbuf; ssize_t len; - kbuf = kmalloc(count, GFP_KERNEL); + kbuf = kmalloc(count, GFP_KERNEL | __GFP_NOWARN); if (!kbuf) return -ENOMEM; |