diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2020-11-01 17:54:13 +0100 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2020-11-01 17:54:13 +0100 |
commit | 17bb415fefedb74d2ff02656cf59e4e3ab92ee20 (patch) | |
tree | 0ada27d370a1e2bfab1b57df9bb02a1a20371662 /kernel/bpf/bpf_iter.c | |
parent | ceb2465c51195967f11f6507538579816ac67cb8 (diff) | |
parent | d95bdca75b3fb41bf185efe164e05aed820081a5 (diff) |
Merge tag 'irqchip-fixes-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent
Pull irqchip fixes from Marc Zyngier:
- A couple of fixes after the IPI as IRQ patches (Kconfig, bcm2836)
- Two SiFive PLIC fixes (irq_set_affinity, hierarchy handling)
- "unmapped events" handling for the ti-sci-inta controller
- Tidying up for the irq-mst driver (static functions, Kconfig)
- Small cleanup in the Renesas irqpin driver
- STM32 exti can now handle LP timer events
Diffstat (limited to 'kernel/bpf/bpf_iter.c')
-rw-r--r-- | kernel/bpf/bpf_iter.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c index b6715964b685..8faa2ce89396 100644 --- a/kernel/bpf/bpf_iter.c +++ b/kernel/bpf/bpf_iter.c @@ -67,6 +67,9 @@ static void bpf_iter_done_stop(struct seq_file *seq) iter_priv->done_stop = true; } +/* maximum visited objects before bailing out */ +#define MAX_ITER_OBJECTS 1000000 + /* bpf_seq_read, a customized and simpler version for bpf iterator. * no_llseek is assumed for this file. * The following are differences from seq_read(): @@ -79,7 +82,7 @@ static ssize_t bpf_seq_read(struct file *file, char __user *buf, size_t size, { struct seq_file *seq = file->private_data; size_t n, offs, copied = 0; - int err = 0; + int err = 0, num_objs = 0; void *p; mutex_lock(&seq->lock); @@ -135,6 +138,7 @@ static ssize_t bpf_seq_read(struct file *file, char __user *buf, size_t size, while (1) { loff_t pos = seq->index; + num_objs++; offs = seq->count; p = seq->op->next(seq, p, &seq->index); if (pos == seq->index) { @@ -153,6 +157,15 @@ static ssize_t bpf_seq_read(struct file *file, char __user *buf, size_t size, if (seq->count >= size) break; + if (num_objs >= MAX_ITER_OBJECTS) { + if (offs == 0) { + err = -EAGAIN; + seq->op->stop(seq, p); + goto done; + } + break; + } + err = seq->op->show(seq, p); if (err > 0) { bpf_iter_dec_seq_num(seq); |