From: Jiufei Xue jiufei.xue@linux.alibaba.com

[ Upstream commit 8c40292be9169a9cbe19aadd1a6fc60cbd1af82f ]

Syzkaller hit 'WARNING in __alloc_pages_nodemask' bug.

WARNING: CPU: 1 PID: 1473 at mm/page_alloc.c:4377 __alloc_pages_nodemask+0x4da/0x2130 Kernel panic - not syncing: panic_on_warn set ...

Call Trace: alloc_pages_current+0xb1/0x1e0 kmalloc_order+0x1f/0x60 kmalloc_order_trace+0x1d/0x120 fb_alloc_cmap_gfp+0x85/0x2b0 fb_set_user_cmap+0xff/0x370 do_fb_ioctl+0x949/0xa20 fb_ioctl+0xdd/0x120 do_vfs_ioctl+0x186/0x1070 ksys_ioctl+0x89/0xa0 __x64_sys_ioctl+0x74/0xb0 do_syscall_64+0xc8/0x550 entry_SYSCALL_64_after_hwframe+0x49/0xbe

This is a warning about order >= MAX_ORDER and the order is from userspace ioctl. Add flag __NOWARN to silence this warning.

Signed-off-by: Jiufei Xue jiufei.xue@linux.alibaba.com Signed-off-by: Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/video/fbdev/core/fbcmap.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/drivers/video/fbdev/core/fbcmap.c b/drivers/video/fbdev/core/fbcmap.c index 68a113594808f..2811c4afde01c 100644 --- a/drivers/video/fbdev/core/fbcmap.c +++ b/drivers/video/fbdev/core/fbcmap.c @@ -94,6 +94,8 @@ int fb_alloc_cmap_gfp(struct fb_cmap *cmap, int len, int transp, gfp_t flags) int size = len * sizeof(u16); int ret = -ENOMEM;

+ flags |= __GFP_NOWARN; + if (cmap->len != len) { fb_dealloc_cmap(cmap); if (!len)