In contrast to other parameters written into /proc/sys/kernel/core_pattern that never fail we can validate enabling the new AF_UNIX support. This is obviously racy as hell but it's always been that way. Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx> --- fs/coredump.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/fs/coredump.c b/fs/coredump.c index d61e15d855d2..0f00f77be988 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -1200,10 +1200,21 @@ void validate_coredump_safety(void) static int proc_dostring_coredump(const struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { - int error = proc_dostring(table, write, buffer, lenp, ppos); + int error; + ssize_t retval; + char old_core_pattern[CORENAME_MAX_SIZE]; - if (!error) - validate_coredump_safety(); + retval = strscpy(old_core_pattern, core_pattern, CORENAME_MAX_SIZE); + + error = proc_dostring(table, write, buffer, lenp, ppos); + if (error) + return error; + if (core_pattern[0] == '@' && strcmp(core_pattern, "@linuxafsk/coredump.socket")) { + strscpy(core_pattern, old_core_pattern, retval + 1); + return -EINVAL; + } + + validate_coredump_safety(); return error; } -- 2.47.2