diff options
| author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2024-12-16 19:38:40 +0900 |
|---|---|---|
| committer | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2024-12-16 19:41:29 +0900 |
| commit | 3df7546fc03b8f004eee0b9e3256369f7d096685 (patch) | |
| tree | 94564a32dcd3a40fec843e9d9017792f2592c1c3 | |
| parent | 78d4f34e2115b517bcbfe7ec0d018bbbb6f9b0b8 (diff) | |
| download | lwn-3df7546fc03b8f004eee0b9e3256369f7d096685.tar.gz lwn-3df7546fc03b8f004eee0b9e3256369f7d096685.zip | |
tomoyo: don't emit warning in tomoyo_write_control()
syzbot is reporting too large allocation warning at tomoyo_write_control(),
for one can write a very very long line without new line character. To fix
this warning, I use __GFP_NOWARN rather than checking for KMALLOC_MAX_SIZE,
for practically a valid line should be always shorter than 32KB where the
"too small to fail" memory-allocation rule applies.
One might try to write a valid line that is longer than 32KB, but such
request will likely fail with -ENOMEM. Therefore, I feel that separately
returning -EINVAL when a line is longer than KMALLOC_MAX_SIZE is redundant.
There is no need to distinguish over-32KB and over-KMALLOC_MAX_SIZE.
Reported-by: syzbot+7536f77535e5210a5c76@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=7536f77535e5210a5c76
Reported-by: Leo Stone <leocstone@gmail.com>
Closes: https://lkml.kernel.org/r/20241216021459.178759-2-leocstone@gmail.com
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
| -rw-r--r-- | security/tomoyo/common.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c index 5c7b059a332a..972664962e8f 100644 --- a/security/tomoyo/common.c +++ b/security/tomoyo/common.c @@ -2665,7 +2665,7 @@ ssize_t tomoyo_write_control(struct tomoyo_io_buffer *head, if (head->w.avail >= head->writebuf_size - 1) { const int len = head->writebuf_size * 2; - char *cp = kzalloc(len, GFP_NOFS); + char *cp = kzalloc(len, GFP_NOFS | __GFP_NOWARN); if (!cp) { error = -ENOMEM; |