From 9eb78c25327548b905598975aa3ded4ef244b94a Mon Sep 17 00:00:00 2001

From: Artem Labazov <123321artyom@gmail.com>

Date: Mon, 7 Dec 2020 09:04:36 +0900

Subject: [Backport 9eb78c253275] exfat: Avoid allocating upcase table using

 kcalloc()

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 kvcalloc() to eliminate the issue.

Fixes: 370e812b3ec1 ("exfat: add nls operations")

Cc: stable@vger.kernel.org #v5.7+

Signed-off-by: Artem Labazov <123321artyom@gmail.com>

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

---

 src/nls.c | 6 +++---

 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/nls.c b/src/nls.c

index 675d0e7058c5a01afe9bdcba4c915e983184c639..314d5407a1be50ac2c789c8a58afda8e1baec413 100644

--- a/src/nls.c

+++ b/src/nls.c

@@ -659,7 +659,7 @@ 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 = kvcalloc(UTBL_COUNT, sizeof(unsigned short), GFP_KERNEL);

 	if (!upcase_table)

 		return -ENOMEM;

@@ -715,7 +715,7 @@ 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 = kvcalloc(UTBL_COUNT, sizeof(unsigned short), GFP_KERNEL);

 	if (!upcase_table)

 		return -ENOMEM;

@@ -803,5 +803,5 @@ int exfat_create_upcase_table(struct super_block *sb)

 void exfat_free_upcase_table(struct exfat_sb_info *sbi)

 {

-	kfree(sbi->vol_utbl);

+	kvfree(sbi->vol_utbl);

 }

-- 

2.31.1