diff options
author | Andrey Skvortsov <andrej.skvortzov@gmail.com> | 2024-09-23 19:48:43 +0300 |
---|---|---|
committer | Andrew Morton <akpm@linux-foundation.org> | 2024-09-27 00:01:44 +0300 |
commit | 486fd58af7ac1098b68370b1d4d9f94a2a1c7124 (patch) | |
tree | 19e6a9dcca1bca5f273732ccf89f81bd00b0fb86 | |
parent | a530bbc53826c607f64e8ee466c3351efaf6aea5 (diff) | |
download | linux-486fd58af7ac1098b68370b1d4d9f94a2a1c7124.tar.xz |
zram: don't free statically defined names
When CONFIG_ZRAM_MULTI_COMP isn't set ZRAM_SECONDARY_COMP can hold
default_compressor, because it's the same offset as ZRAM_PRIMARY_COMP, so
we need to make sure that we don't attempt to kfree() the statically
defined compressor name.
This is detected by KASAN.
==================================================================
Call trace:
kfree+0x60/0x3a0
zram_destroy_comps+0x98/0x198 [zram]
zram_reset_device+0x22c/0x4a8 [zram]
reset_store+0x1bc/0x2d8 [zram]
dev_attr_store+0x44/0x80
sysfs_kf_write+0xfc/0x188
kernfs_fop_write_iter+0x28c/0x428
vfs_write+0x4dc/0x9b8
ksys_write+0x100/0x1f8
__arm64_sys_write+0x74/0xb8
invoke_syscall+0xd8/0x260
el0_svc_common.constprop.0+0xb4/0x240
do_el0_svc+0x48/0x68
el0_svc+0x40/0xc8
el0t_64_sync_handler+0x120/0x130
el0t_64_sync+0x190/0x198
==================================================================
Link: https://lkml.kernel.org/r/20240923164843.1117010-1-andrej.skvortzov@gmail.com
Fixes: 684826f8271a ("zram: free secondary algorithms names")
Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reported-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
Closes: https://lore.kernel.org/lkml/57130e48-dbb6-4047-a8c7-ebf5aaea93f4@linux.vnet.ibm.com/
Tested-by: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Venkat Rao Bagalkote <venkat88@linux.vnet.ibm.com>
Cc: Chris Li <chrisl@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
-rw-r--r-- | drivers/block/zram/zram_drv.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index c3d245617083..ad9c9bc3ccfc 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -2115,8 +2115,10 @@ static void zram_destroy_comps(struct zram *zram) zram->num_active_comps--; } - for (prio = ZRAM_SECONDARY_COMP; prio < ZRAM_MAX_COMPS; prio++) { - kfree(zram->comp_algs[prio]); + for (prio = ZRAM_PRIMARY_COMP; prio < ZRAM_MAX_COMPS; prio++) { + /* Do not free statically defined compression algorithms */ + if (zram->comp_algs[prio] != default_compressor) + kfree(zram->comp_algs[prio]); zram->comp_algs[prio] = NULL; } |