From: Artem Labazov <123321artyom@gmail.com>
To: unlisted-recipients:; (no To-header on input)
Cc: 123321artyom@gmail.com, stable@vger.kernel.org,
Namjae Jeon <namjae.jeon@samsung.com>,
Sungjong Seo <sj1557.seo@samsung.com>,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] exfat: Avoid allocating upcase table using kcalloc()
Date: Tue, 24 Nov 2020 21:50:43 +0300 [thread overview]
Message-ID: <20201124185043.4037182-1-123321artyom@gmail.com> (raw)
The table for Unicode upcase conversion requires an order-5 allocation,
which may fail on a highly-fragmented system:
pool-udisksd: page allocation failure: order:5, mode:0x40dc0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO), nodemask=(null),cpuset=/,mems_allowed=0
CPU: 4 PID: 3756880 Comm: pool-udisksd Tainted: G U 5.8.10-200.fc32.x86_64 #1
Hardware name: Dell Inc. XPS 13 9360/0PVG6D, BIOS 2.13.0 11/14/2019
Call Trace:
dump_stack+0x6b/0x88
warn_alloc.cold+0x75/0xd9
? _cond_resched+0x16/0x40
? __alloc_pages_direct_compact+0x144/0x150
__alloc_pages_slowpath.constprop.0+0xcfa/0xd30
? __schedule+0x28a/0x840
? __wait_on_bit_lock+0x92/0xa0
__alloc_pages_nodemask+0x2df/0x320
kmalloc_order+0x1b/0x80
kmalloc_order_trace+0x1d/0xa0
exfat_create_upcase_table+0x115/0x390 [exfat]
exfat_fill_super+0x3ef/0x7f0 [exfat]
? sget_fc+0x1d0/0x240
? exfat_init_fs_context+0x120/0x120 [exfat]
get_tree_bdev+0x15c/0x250
vfs_get_tree+0x25/0xb0
do_mount+0x7c3/0xaf0
? copy_mount_options+0xab/0x180
__x64_sys_mount+0x8e/0xd0
do_syscall_64+0x4d/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Make the driver use vmalloc() to eliminate the issue.
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Artem Labazov <123321artyom@gmail.com>
---
fs/exfat/nls.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/exfat/nls.c b/fs/exfat/nls.c
index 675d0e7058c5..e415794e3ffc 100644
--- a/fs/exfat/nls.c
+++ b/fs/exfat/nls.c
@@ -6,6 +6,7 @@
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/buffer_head.h>
+#include <linux/vmalloc.h>
#include <asm/unaligned.h>
#include "exfat_raw.h"
@@ -659,7 +660,7 @@ static int exfat_load_upcase_table(struct super_block *sb,
unsigned char skip = false;
unsigned short *upcase_table;
- upcase_table = kcalloc(UTBL_COUNT, sizeof(unsigned short), GFP_KERNEL);
+ upcase_table = vmalloc(UTBL_COUNT * sizeof(unsigned short));
if (!upcase_table)
return -ENOMEM;
@@ -715,7 +716,7 @@ static int exfat_load_default_upcase_table(struct super_block *sb)
unsigned short uni = 0, *upcase_table;
unsigned int index = 0;
- upcase_table = kcalloc(UTBL_COUNT, sizeof(unsigned short), GFP_KERNEL);
+ upcase_table = vmalloc(UTBL_COUNT * sizeof(unsigned short));
if (!upcase_table)
return -ENOMEM;
--
2.26.2
next reply other threads:[~2020-11-24 18:51 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-24 18:50 Artem Labazov [this message]
[not found] <CGME20201124194858epcas1p49cacda6a9b4877ff125f25f4dc5fcadf@epcas1p4.samsung.com>
2020-11-24 19:47 ` [PATCH] exfat: Avoid allocating upcase table using kcalloc() Artem Labazov
2020-11-24 22:17 ` David Laight
2020-12-02 4:58 ` Sungjong Seo
2020-12-04 12:57 ` Artem Labazov
2020-12-07 6:23 ` Sungjong Seo
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