On (20/10/14 16:19), Naresh Kamboju wrote:
> Crash log:
> --------------
> [ 221.921944] oom-kill:constraint=CONSTRAINT_MEMCG,nodemask=(null),cpuset=c,mems_allowed=0,oom_memcg=/0,task_memcg=in
> [ 221.922108] ==================================================================
> [ 221.922111] BUG: KASAN: global-out-of-bounds in vprintk_store+0x362/0x3d0
> [ 221.922112] Write of size 2 at addr ffffffffba51dbcd by task
> memcg_test_1/11282
> [ 221.922113]
> [ 221.922114] CPU: 1 PID: 11282 Comm: memcg_test_1 Not tainted
> 5.9.0-next-20201013 #1
> [ 221.922116] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS
> 2.0b 07/27/2017
> [ 221.922116] Call Trace:
> [ 221.922117] dump_stack+0xa4/0xd9
> [ 221.922118] print_address_description.constprop.0+0x21/0x210
> [ 221.922119] ? _raw_write_lock_bh+0xe0/0xe0
> [ 221.922120] ? vprintk_store+0x362/0x3d0
> [ 221.922121] kasan_report.cold+0x37/0x7c
> [ 221.922122] ? vprintk_store+0x362/0x3d0
> [ 221.922123] check_memory_region+0x18c/0x1f0
> [ 221.922124] memcpy+0x3c/0x60
> [ 221.922125] vprintk_store+0x362/0x3d0
> [ 221.922125] ? __ia32_sys_syslog+0x50/0x50
> [ 221.922126] ? _raw_spin_lock_irqsave+0x9b/0x100
> [ 221.922127] ? _raw_spin_lock_irq+0xf0/0xf0
> [ 221.922128] ? __kasan_check_write+0x14/0x20
> [ 221.922129] vprintk_emit+0x8d/0x1f0
> [ 221.922130] vprintk_default+0x1d/0x20
> [ 221.922131] vprintk_func+0x5a/0x100
> [ 221.922132] printk+0xb2/0xe3
> [ 221.922133] ? swsusp_write.cold+0x189/0x189
> [ 221.922134] ? kernfs_vfs_xattr_set+0x60/0x60
> [ 221.922134] ? _raw_write_lock_bh+0xe0/0xe0
> [ 221.922135] ? trace_hardirqs_on+0x38/0x100
> [ 221.922136] pr_cont_kernfs_path.cold+0x49/0x4b
A side note,
So this brings the question:
#define PATH_MAX 4096
static char kernfs_pr_cont_buf[PATH_MAX];
void pr_cont_kernfs_path(struct kernfs_node *kn)
{
...
if (sz >= sizeof(kernfs_pr_cont_buf)) {
pr_cont("(name too long)");
goto out;
}
pr_cont("%s", kernfs_pr_cont_buf);
...
}
Do we still want to limit printk line to 1024?
There are functions that want longer lines (e.g. kernel boot command
line).
-ss
