The patch titled
Subject: zram: fix potential UAF of zram table
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
zram-fix-potential-uaf-of-zram-table.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/zram-fix-potential-uaf-of-zram-table.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Kairui Song <kasong@xxxxxxxxxxx>
Subject: zram: fix potential UAF of zram table
Date: Tue, 7 Jan 2025 14:54:46 +0800
If zram_meta_alloc failed early, it frees allocated zram->table without
setting it NULL. Which will potentially cause zram_meta_free to access
the table if user reset an failed and uninitialized device.
Link: https://lkml.kernel.org/r/20250107065446.86928-1-ryncsn@xxxxxxxxx
Fixes: 74363ec674cb ("zram: fix uninitialized ZRAM not releasing backing device")
Signed-off-by: Kairui Song <kasong@xxxxxxxxxxx>
Reviewed-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/block/zram/zram_drv.c | 1 +
1 file changed, 1 insertion(+)
--- a/drivers/block/zram/zram_drv.c~zram-fix-potential-uaf-of-zram-table
+++ a/drivers/block/zram/zram_drv.c
@@ -1468,6 +1468,7 @@ static bool zram_meta_alloc(struct zram
zram->mem_pool = zs_create_pool(zram->disk->disk_name);
if (!zram->mem_pool) {
vfree(zram->table);
+ zram->table = NULL;
return false;
}
_
Patches currently in -mm which might be from kasong@xxxxxxxxxxx are
zram-fix-potential-uaf-of-zram-table.patch
mm-memcontrol-avoid-duplicated-memcg-enable-check.patch
mm-swap_cgroup-remove-swap_cgroup_cmpxchg.patch
mm-swap_cgroup-remove-global-swap-cgroup-lock.patch
mm-swap_cgroup-decouple-swap-cgroup-recording-and-clearing.patch
mm-swap-minor-clean-up-for-swap-entry-allocation.patch
mm-swap-fold-swap_info_get_cont-in-the-only-caller.patch
mm-swap-remove-old-allocation-path-for-hdd.patch
mm-swap-use-cluster-lock-for-hdd.patch
mm-swap-clean-up-device-availability-check.patch
mm-swap-clean-up-plist-removal-and-adding.patch
mm-swap-hold-a-reference-during-scan-and-cleanup-flag-usage.patch
mm-swap-use-an-enum-to-define-all-cluster-flags-and-wrap-flags-changes.patch
mm-swap-reduce-contention-on-device-lock.patch
mm-swap-simplify-percpu-cluster-updating.patch
mm-swap-introduce-a-helper-for-retrieving-cluster-from-offset.patch
mm-swap-use-a-global-swap-cluster-for-non-rotation-devices.patch
mm-swap_slots-remove-slot-cache-for-freeing-path.patch
