From f63a9df7e3f9f842945d292a19d9938924f066f9 Mon Sep 17 00:00:00 2001 From: Marc Buerg Date: Wed, 25 Mar 2026 23:29:50 +0100 Subject: sysctl: fix uninitialized variable in proc_do_large_bitmap proc_do_large_bitmap() does not initialize variable c, which is expected to be set to a trailing character by proc_get_long(). However, proc_get_long() only sets c when the input buffer contains a trailing character after the parsed value. If c is not initialized it may happen to contain a '-'. If this is the case proc_do_large_bitmap() expects to be able to parse a second part of the input buffer. If there is no second part an unjustified -EINVAL will be returned. Initialize c to 0 to prevent returning -EINVAL on valid input. Fixes: 9f977fb7ae9d ("sysctl: add proc_do_large_bitmap") Signed-off-by: Marc Buerg Reviewed-by: Joel Granados Signed-off-by: Joel Granados --- kernel/sysctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/sysctl.c') diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 9d3a666ffde1..c9efb17cc255 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1118,7 +1118,7 @@ int proc_do_large_bitmap(const struct ctl_table *table, int dir, unsigned long bitmap_len = table->maxlen; unsigned long *bitmap = *(unsigned long **) table->data; unsigned long *tmp_bitmap = NULL; - char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c; + char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c = 0; if (!bitmap || !bitmap_len || !left || (*ppos && SYSCTL_KERN_TO_USER(dir))) { *lenp = 0; -- cgit v1.2.3