Do not silently autocorrect bad recompression priority parameter value and just error out. Suggested-by: Minchan Kim Signed-off-by: Sergey Senozhatsky --- drivers/block/zram/zram_drv.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 4eaec24a23fe..53e0bbf9d6ec 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -2524,19 +2524,16 @@ static ssize_t recompress_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { + u32 prio = ZRAM_SECONDARY_COMP, prio_max = ZRAM_MAX_COMPS; struct zram *zram = dev_to_zram(dev); char *args, *param, *val, *algo = NULL; u64 num_recomp_pages = ULLONG_MAX; struct zram_pp_ctl *ctl = NULL; struct zram_pp_slot *pps; u32 mode = 0, threshold = 0; - u32 prio, prio_max; struct page *page = NULL; ssize_t ret; - prio = ZRAM_SECONDARY_COMP; - prio_max = zram->num_active_comps; - args = skip_spaces(buf); while (*args) { args = next_arg(args, ¶m, &val); @@ -2586,10 +2583,7 @@ static ssize_t recompress_store(struct device *dev, if (ret) return ret; - if (prio == ZRAM_PRIMARY_COMP) - prio = ZRAM_SECONDARY_COMP; - - prio_max = prio + 1; + prio_max = min(prio + 1, ZRAM_MAX_COMPS); continue; } } @@ -2609,7 +2603,7 @@ static ssize_t recompress_store(struct device *dev, continue; if (!strcmp(zram->comp_algs[prio], algo)) { - prio_max = prio + 1; + prio_max = min(prio + 1, ZRAM_MAX_COMPS); found = true; break; } @@ -2627,6 +2621,11 @@ static ssize_t recompress_store(struct device *dev, goto out; } + if (prio < ZRAM_SECONDARY_COMP || prio >= ZRAM_MAX_COMPS) { + ret = -EINVAL; + goto out; + } + page = alloc_page(GFP_KERNEL); if (!page) { ret = -ENOMEM; -- 2.53.0.473.g4a7958ca14-goog