summaryrefslogtreecommitdiffstats
path: root/kernel/debug/kdb
diff options
context:
space:
mode:
authorDan Carpenter <dan.carpenter@oracle.com>2019-05-06 15:50:18 +0300
committerDaniel Thompson <daniel.thompson@linaro.org>2019-05-12 09:50:44 +0100
commitb586627e10f57ee3aa8f0cfab0d6f7dc4ae63760 (patch)
tree179466e3716826e61ead28ece56e385e4b99b2b7 /kernel/debug/kdb
parentecebc5ce59a003163eb608ace38a01d7ffeb0a95 (diff)
downloadlinux-b586627e10f57ee3aa8f0cfab0d6f7dc4ae63760.tar.bz2
kdb: do a sanity check on the cpu in kdb_per_cpu()
The "whichcpu" comes from argv[3]. The cpu_online() macro looks up the cpu in a bitmap of online cpus, but if the value is too high then it could read beyond the end of the bitmap and possibly Oops. Fixes: 5d5314d6795f ("kdb: core for kgdb back end (1 of 2)") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Diffstat (limited to 'kernel/debug/kdb')
-rw-r--r--kernel/debug/kdb/kdb_main.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index fc96dbf8d9de..9ecfa37c7fbf 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -2583,7 +2583,7 @@ static int kdb_per_cpu(int argc, const char **argv)
diag = kdbgetularg(argv[3], &whichcpu);
if (diag)
return diag;
- if (!cpu_online(whichcpu)) {
+ if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
kdb_printf("cpu %ld is not online\n", whichcpu);
return KDB_BADCPUNUM;
}