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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Stat-Signature: dys3idpgesnbmcu5wk9f9iqebgd9qtnw X-Rspamd-Queue-Id: ECDB140005 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1722916277-535327 X-HE-Meta: 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 alGLpZLK xUiQGu319vHy7kRR7zrUyeRVJ513m9HAcRK6YBvyFJmAzIshbpJixxjzjym2aBcJzC8r7NfWf0Lfqu2dv2ZxCB8kMHZObS1EIRc3uJsES7B9w3YTLlsJTj5/OZK5sZB2l3yb2BDMwJ4mRiUWAXgHwrOvDbaUoMlax9PyJXGB2OHoSul0Oqg2RQGgCWJo0sRDvIloSS/j4BBxJLSCWckj2yxIcbJtCUhc16AyfIPi37zqXyIzyJCaV1W01zY8Nb4vOdCcjaNPGdztmMzFBCfbokqL5TD5OdvaK2JuBbuDtgi+c4XAkW0ikcXdbvrJU234WTqH4v8gsDqxkgHzqJMIrm0XQwy/boTWftXwqG4eICQjuwnePpBLa3XXLTqEil16JKRQyw2neHc3U11CYjVWxPwa4dwygvcHTUegSuoayP7KuylE3YVaiUaTK/3bOaHMlUIaYkynnCEidEnERID9LNXHJU1mcqhtgBUSJ X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Aug 6, 2024 at 11:10=E2=80=AFAM Linus Torvalds wrote: > > On Mon, 5 Aug 2024 at 20:01, Yafang Shao wrote: > > > > One concern about removing the BUILD_BUG_ON() is that if we extend > > TASK_COMM_LEN to a larger size, such as 24, the caller with a > > hardcoded 16-byte buffer may overflow. > > No, not at all. Because get_task_comm() - and the replacements - would > never use TASK_COMM_LEN. > > They'd use the size of the *destination*. That's what the code already do= es: > > #define get_task_comm(buf, tsk) ({ \ > ... > __get_task_comm(buf, sizeof(buf), tsk); \ > > note how it uses "sizeof(buf)". > > Now, it might be a good idea to also verify that 'buf' is an actual > array, and that this code doesn't do some silly "sizeof(ptr)" thing. > > We do have a helper for that, so we could do something like > > #define get_task_comm(buf, tsk) \ > strscpy_pad(buf, __must_be_array(buf)+sizeof(buf), (tsk)->comm) > > as a helper macro for this all. > > (Although I'm not convinced we generally want the "_pad()" version, > but whatever). > Will do it. Thanks for your explanation. --=20 Regards Yafang