From 43ac6874069c9e6a01b3bce018778a230c153e75 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Wed, 2 Jan 2019 15:36:54 +0100 Subject: [PATCH] mtd: Check add_mtd_device() ret code [ Upstream commit 2b6f0090a3335b7bdd03ca520c35591159463041 ] add_mtd_device() can fail. We should always check its return value and gracefully handle the failure case. Fix the call sites where this not done (in mtdpart.c) and add a __must_check attribute to the prototype to avoid this kind of mistakes. Signed-off-by: Boris Brezillon Signed-off-by: Sasha Levin --- drivers/mtd/mtdcore.h | 2 +- drivers/mtd/mtdpart.c | 36 +++++++++++++++++++++++++++++++----- 2 files changed, 32 insertions(+), 6 deletions(-) diff --git a/drivers/mtd/mtdcore.h b/drivers/mtd/mtdcore.h index 37accfd0400e..24480b75a88d 100644 --- a/drivers/mtd/mtdcore.h +++ b/drivers/mtd/mtdcore.h @@ -7,7 +7,7 @@ extern struct mutex mtd_table_mutex; struct mtd_info *__mtd_next_device(int i); -int add_mtd_device(struct mtd_info *mtd); +int __must_check add_mtd_device(struct mtd_info *mtd); int del_mtd_device(struct mtd_info *mtd); int add_mtd_partitions(struct mtd_info *, const struct mtd_partition *, int); int del_mtd_partitions(struct mtd_info *); diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c index a308e707392d..27d9785487d6 100644 --- a/drivers/mtd/mtdpart.c +++ b/drivers/mtd/mtdpart.c @@ -684,10 +684,22 @@ int mtd_add_partition(struct mtd_info *parent, const char *name, list_add(&new->list, &mtd_partitions); mutex_unlock(&mtd_partitions_mutex); - add_mtd_device(&new->mtd); + ret = add_mtd_device(&new->mtd); + if (ret) + goto err_remove_part; mtd_add_partition_attrs(new); + return 0; + +err_remove_part: + mutex_lock(&mtd_partitions_mutex); + list_del(&new->list); + mutex_unlock(&mtd_partitions_mutex); + + free_partition(new); + pr_info("%s:%i\n", __func__, __LINE__); + return ret; } EXPORT_SYMBOL_GPL(mtd_add_partition); @@ -778,22 +790,31 @@ int add_mtd_partitions(struct mtd_info *master, { struct mtd_part *slave; uint64_t cur_offset = 0; - int i; + int i, ret; printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name); for (i = 0; i < nbparts; i++) { slave = allocate_partition(master, parts + i, i, cur_offset); if (IS_ERR(slave)) { - del_mtd_partitions(master); - return PTR_ERR(slave); + ret = PTR_ERR(slave); + goto err_del_partitions; } mutex_lock(&mtd_partitions_mutex); list_add(&slave->list, &mtd_partitions); mutex_unlock(&mtd_partitions_mutex); - add_mtd_device(&slave->mtd); + ret = add_mtd_device(&slave->mtd); + if (ret) { + mutex_lock(&mtd_partitions_mutex); + list_del(&slave->list); + mutex_unlock(&mtd_partitions_mutex); + + free_partition(slave); + goto err_del_partitions; + } + mtd_add_partition_attrs(slave); if (parts[i].types) mtd_parse_part(slave, parts[i].types); @@ -802,6 +823,11 @@ int add_mtd_partitions(struct mtd_info *master, } return 0; + +err_del_partitions: + del_mtd_partitions(master); + + return ret; } static DEFINE_SPINLOCK(part_parser_lock); -- 2.20.1