6.13-stable review patch. If anyone has any objections, please let me know.
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From: Zhihao Cheng chengzhihao1@huawei.com
[ Upstream commit 844c6fdc13cf3d9d251533631988a58f8356a8c8 ]
Commit 5580cdae05ae ("ubi: wl: Close down wear-leveling before nand is suspended") added a reboot notification in UBI layer to shutdown the wear-leveling subsystem, which imported an UAF problem[1]. Besides that, the method also brings other potential UAF problems, for example: reboot kworker ubi_wl_reboot_notifier ubi_wl_close ubi_fastmap_close kfree(ubi->fm) update_fastmap_work_fn ubi_update_fastmap old_fm = ubi->fm if (old_fm && old_fm->e[i]) // UAF!
Actually, the problem fixed by commit 5580cdae05ae ("ubi: wl: Close down wear-leveling before nand is suspended") has been solved by commit 8cba323437a4 ("mtd: rawnand: protect access to rawnand devices while in suspend"), which was discussed in [2]. So we can revert the commit 5580cdae05ae ("ubi: wl: Close down wear-leveling before nand is suspended") directly.
[1] https://lore.kernel.org/linux-mtd/20241208175211.9406-2-dennis.lamerice@gmai... [2] https://lore.kernel.org/all/9bf76f5d-12a4-46ff-90d4-4a7f0f47c381@axis.com/
Fixes: 5580cdae05ae ("ubi: wl: Close down wear-leveling before nand is suspended") Reported-by: Dennis Lam dennis.lamerice@gmail.com Closes: https://lore.kernel.org/linux-mtd/20241208175211.9406-2-dennis.lamerice@gmai... Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com Acked-by: Mårten Lindahl marten.lindahl@axis.com Signed-off-by: Richard Weinberger richard@nod.at Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mtd/ubi/ubi.h | 2 -- drivers/mtd/ubi/wl.c | 21 --------------------- 2 files changed, 23 deletions(-)
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index 26cc53ad34ec7..c792b9bcab9bc 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -549,7 +549,6 @@ struct ubi_debug_info { * @peb_buf: a buffer of PEB size used for different purposes * @buf_mutex: protects @peb_buf * @ckvol_mutex: serializes static volume checking when opening - * @wl_reboot_notifier: close all wear-leveling work before reboot * * @dbg: debugging information for this UBI device */ @@ -652,7 +651,6 @@ struct ubi_device { void *peb_buf; struct mutex buf_mutex; struct mutex ckvol_mutex; - struct notifier_block wl_reboot_notifier;
struct ubi_debug_info dbg; }; diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c index 4f6f339d8fb8a..fbd399cf65033 100644 --- a/drivers/mtd/ubi/wl.c +++ b/drivers/mtd/ubi/wl.c @@ -89,7 +89,6 @@ #include <linux/crc32.h> #include <linux/freezer.h> #include <linux/kthread.h> -#include <linux/reboot.h> #include "ubi.h" #include "wl.h"
@@ -128,8 +127,6 @@ static int self_check_in_wl_tree(const struct ubi_device *ubi, struct ubi_wl_entry *e, struct rb_root *root); static int self_check_in_pq(const struct ubi_device *ubi, struct ubi_wl_entry *e); -static int ubi_wl_reboot_notifier(struct notifier_block *n, - unsigned long state, void *cmd);
/** * wl_tree_add - add a wear-leveling entry to a WL RB-tree. @@ -1953,13 +1950,6 @@ int ubi_wl_init(struct ubi_device *ubi, struct ubi_attach_info *ai) if (!ubi->ro_mode && !ubi->fm_disabled) ubi_ensure_anchor_pebs(ubi); #endif - - if (!ubi->wl_reboot_notifier.notifier_call) { - ubi->wl_reboot_notifier.notifier_call = ubi_wl_reboot_notifier; - ubi->wl_reboot_notifier.priority = 1; /* Higher than MTD */ - register_reboot_notifier(&ubi->wl_reboot_notifier); - } - return 0;
out_free: @@ -2005,17 +1995,6 @@ void ubi_wl_close(struct ubi_device *ubi) kfree(ubi->lookuptbl); }
-static int ubi_wl_reboot_notifier(struct notifier_block *n, - unsigned long state, void *cmd) -{ - struct ubi_device *ubi; - - ubi = container_of(n, struct ubi_device, wl_reboot_notifier); - ubi_wl_close(ubi); - - return NOTIFY_DONE; -} - /** * self_check_ec - make sure that the erase counter of a PEB is correct. * @ubi: UBI device description object