[PATCH 5.15 441/846] powerpc/xive: Add missing null check after calling kmalloc

[Greg Kroah-Hartman]

From: Ammar Faizi <ammarfaizi2@xxxxxxxxx>

[ Upstream commit 18dbfcdedc802f9500b2c29794f22a31d27639c0 ]

Commit 930914b7d528fc ("powerpc/xive: Add a debugfs file to dump
internal XIVE state") forgot to add a null check.

Add it.

Fixes: 930914b7d528fc6b0249bffc00564100bcf6ef75 ("powerpc/xive: Add a debugfs file to dump internal XIVE state")
Signed-off-by: Ammar Faizi <ammarfaizi2@xxxxxxxxx>
Reviewed-by: Cédric Le Goater <clg@xxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20211226135314.251221-1-ammar.faizi@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/powerpc/sysdev/xive/spapr.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c
index f143b6f111ac0..1179632560b8d 100644
--- a/arch/powerpc/sysdev/xive/spapr.c
+++ b/arch/powerpc/sysdev/xive/spapr.c
@@ -653,6 +653,9 @@ static int xive_spapr_debug_show(struct seq_file *m, void *private)
 	struct xive_irq_bitmap *xibm;
 	char *buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 
+	if (!buf)
+		return -ENOMEM;
+
 	list_for_each_entry(xibm, &xive_irq_bitmaps, list) {
 		memset(buf, 0, PAGE_SIZE);
 		bitmap_print_to_pagebuf(true, buf, xibm->bitmap, xibm->count);
-- 
2.34.1