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TO_DN_SOME(0.00)[]; DNSWL_BLOCKED(0.00)[2a07:de40:b2bf:1b::12bd:from]; SPAMHAUS_XBL(0.00)[2a07:de40:b2bf:1b::12bd:from]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com] X-Spamd-Bar: +++++++++++++++ X-Rspamd-Queue-Id: EDE045BED2 X-Spam-Flag: YES X-Spam-Score: 15.13 X-Spam-Level: *************** X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Rspamd-Action: add header X-Spam: Yes Content-Type: text/plain; charset="utf-8" kallsyms_lookup_buildid() copies the symbol name into the given buffer so that it can be safely read anytime later. But it just copies pointers to mod->name and mod->build_id which might get reused after the related struct module gets removed. The lifetime of struct module is synchronized using RCU. Take the rcu read lock for the entire __sprint_symbol(). Reviewed-by: Aaron Tomlin Signed-off-by: Petr Mladek --- kernel/kallsyms.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 5bc1646f8639..202d39f5493a 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -471,6 +471,9 @@ static int __sprint_symbol(char *buffer, unsigned long = address, unsigned long offset, size; int len; =20 + /* Prevent module removal until modname and modbuildid are printed */ + guard(rcu)(); + address +=3D symbol_offset; len =3D kallsyms_lookup_buildid(address, &size, &offset, &modname, &build= id, buffer); --=20 2.52.0