linux-stable/fs/quota/quota_v2.c
Eric Dumazet 3d3dc274ce quota: clear padding in v2r1_mem2diskdqb()
Freshly allocated memory contains garbage, better make sure
to init all struct v2r1_disk_dqblk fields to avoid KMSAN report:

BUG: KMSAN: uninit-value in qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
CPU: 0 PID: 23373 Comm: syz-executor.1 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:219
 qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
 v2r1_mem2diskdqb+0x43d/0x710 fs/quota/quota_v2.c:285
 qtree_write_dquot+0x226/0x870 fs/quota/quota_tree.c:394
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_commit+0x4af/0x600 fs/quota/dquot.c:482
 ext4_write_dquot fs/ext4/super.c:5934 [inline]
 ext4_mark_dquot_dirty+0x4d8/0x6a0 fs/ext4/super.c:5985
 mark_dquot_dirty fs/quota/dquot.c:347 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:385 [inline]
 dquot_alloc_inode+0xc05/0x12b0 fs/quota/dquot.c:1755
 __ext4_new_inode+0x8204/0x9d70 fs/ext4/ialloc.c:1155
 ext4_tmpfile+0x41a/0x850 fs/ext4/namei.c:2686
 vfs_tmpfile+0x2a2/0x570 fs/namei.c:3283
 do_tmpfile fs/namei.c:3316 [inline]
 path_openat+0x4035/0x6a90 fs/namei.c:3359
 do_filp_open+0x2b8/0x710 fs/namei.c:3395
 do_sys_openat2+0xa88/0x1140 fs/open.c:1168
 do_sys_open fs/open.c:1184 [inline]
 __do_compat_sys_openat fs/open.c:1242 [inline]
 __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240
 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7ff4549
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f55cd0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 0000000020000000
RDX: 0000000000410481 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:143 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:126
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2907 [inline]
 slab_alloc mm/slub.c:2916 [inline]
 __kmalloc+0x2bb/0x4b0 mm/slub.c:3982
 kmalloc include/linux/slab.h:559 [inline]
 getdqbuf+0x56/0x150 fs/quota/quota_tree.c:52
 qtree_write_dquot+0xf2/0x870 fs/quota/quota_tree.c:378
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_commit+0x4af/0x600 fs/quota/dquot.c:482
 ext4_write_dquot fs/ext4/super.c:5934 [inline]
 ext4_mark_dquot_dirty+0x4d8/0x6a0 fs/ext4/super.c:5985
 mark_dquot_dirty fs/quota/dquot.c:347 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:385 [inline]
 dquot_alloc_inode+0xc05/0x12b0 fs/quota/dquot.c:1755
 __ext4_new_inode+0x8204/0x9d70 fs/ext4/ialloc.c:1155
 ext4_tmpfile+0x41a/0x850 fs/ext4/namei.c:2686
 vfs_tmpfile+0x2a2/0x570 fs/namei.c:3283
 do_tmpfile fs/namei.c:3316 [inline]
 path_openat+0x4035/0x6a90 fs/namei.c:3359
 do_filp_open+0x2b8/0x710 fs/namei.c:3395
 do_sys_openat2+0xa88/0x1140 fs/open.c:1168
 do_sys_open fs/open.c:1184 [inline]
 __do_compat_sys_openat fs/open.c:1242 [inline]
 __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240
 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Fixes: 498c60153e ("quota: Implement quota format with 64-bit space and inode limits")
Link: https://lore.kernel.org/r/20200924183619.4176790-1-edumazet@google.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jan Kara <jack@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2020-09-25 11:15:27 +02:00

413 lines
12 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* vfsv0 quota IO operations on file
*/
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/dqblk_v2.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/quotaops.h>
#include <asm/byteorder.h>
#include "quota_tree.h"
#include "quotaio_v2.h"
MODULE_AUTHOR("Jan Kara");
MODULE_DESCRIPTION("Quota format v2 support");
MODULE_LICENSE("GPL");
static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot);
static void v2r0_disk2memdqb(struct dquot *dquot, void *dp);
static int v2r0_is_id(void *dp, struct dquot *dquot);
static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot);
static void v2r1_disk2memdqb(struct dquot *dquot, void *dp);
static int v2r1_is_id(void *dp, struct dquot *dquot);
static const struct qtree_fmt_operations v2r0_qtree_ops = {
.mem2disk_dqblk = v2r0_mem2diskdqb,
.disk2mem_dqblk = v2r0_disk2memdqb,
.is_id = v2r0_is_id,
};
static const struct qtree_fmt_operations v2r1_qtree_ops = {
.mem2disk_dqblk = v2r1_mem2diskdqb,
.disk2mem_dqblk = v2r1_disk2memdqb,
.is_id = v2r1_is_id,
};
#define QUOTABLOCK_BITS 10
#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
static inline qsize_t v2_stoqb(qsize_t space)
{
return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
}
static inline qsize_t v2_qbtos(qsize_t blocks)
{
return blocks << QUOTABLOCK_BITS;
}
static int v2_read_header(struct super_block *sb, int type,
struct v2_disk_dqheader *dqhead)
{
ssize_t size;
size = sb->s_op->quota_read(sb, type, (char *)dqhead,
sizeof(struct v2_disk_dqheader), 0);
if (size != sizeof(struct v2_disk_dqheader)) {
quota_error(sb, "Failed header read: expected=%zd got=%zd",
sizeof(struct v2_disk_dqheader), size);
if (size < 0)
return size;
return -EIO;
}
return 0;
}
/* Check whether given file is really vfsv0 quotafile */
static int v2_check_quota_file(struct super_block *sb, int type)
{
struct v2_disk_dqheader dqhead;
static const uint quota_magics[] = V2_INITQMAGICS;
static const uint quota_versions[] = V2_INITQVERSIONS;
if (v2_read_header(sb, type, &dqhead))
return 0;
if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] ||
le32_to_cpu(dqhead.dqh_version) > quota_versions[type])
return 0;
return 1;
}
/* Read information header from quota file */
static int v2_read_file_info(struct super_block *sb, int type)
{
struct v2_disk_dqinfo dinfo;
struct v2_disk_dqheader dqhead;
struct quota_info *dqopt = sb_dqopt(sb);
struct mem_dqinfo *info = &dqopt->info[type];
struct qtree_mem_dqinfo *qinfo;
ssize_t size;
unsigned int version;
int ret;
down_read(&dqopt->dqio_sem);
ret = v2_read_header(sb, type, &dqhead);
if (ret < 0)
goto out;
version = le32_to_cpu(dqhead.dqh_version);
if ((info->dqi_fmt_id == QFMT_VFS_V0 && version != 0) ||
(info->dqi_fmt_id == QFMT_VFS_V1 && version != 1)) {
ret = -EINVAL;
goto out;
}
size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
if (size != sizeof(struct v2_disk_dqinfo)) {
quota_error(sb, "Can't read info structure");
if (size < 0)
ret = size;
else
ret = -EIO;
goto out;
}
info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
if (!info->dqi_priv) {
ret = -ENOMEM;
goto out;
}
qinfo = info->dqi_priv;
if (version == 0) {
/* limits are stored as unsigned 32-bit data */
info->dqi_max_spc_limit = 0xffffffffLL << QUOTABLOCK_BITS;
info->dqi_max_ino_limit = 0xffffffff;
} else {
/*
* Used space is stored as unsigned 64-bit value in bytes but
* quota core supports only signed 64-bit values so use that
* as a limit
*/
info->dqi_max_spc_limit = 0x7fffffffffffffffLL; /* 2^63-1 */
info->dqi_max_ino_limit = 0x7fffffffffffffffLL;
}
info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
/* No flags currently supported */
info->dqi_flags = 0;
qinfo->dqi_sb = sb;
qinfo->dqi_type = type;
qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
qinfo->dqi_qtree_depth = qtree_depth(qinfo);
if (version == 0) {
qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
qinfo->dqi_ops = &v2r0_qtree_ops;
} else {
qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
qinfo->dqi_ops = &v2r1_qtree_ops;
}
ret = 0;
out:
up_read(&dqopt->dqio_sem);
return ret;
}
/* Write information header to quota file */
static int v2_write_file_info(struct super_block *sb, int type)
{
struct v2_disk_dqinfo dinfo;
struct quota_info *dqopt = sb_dqopt(sb);
struct mem_dqinfo *info = &dqopt->info[type];
struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
ssize_t size;
down_write(&dqopt->dqio_sem);
spin_lock(&dq_data_lock);
info->dqi_flags &= ~DQF_INFO_DIRTY;
dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
/* No flags currently supported */
dinfo.dqi_flags = cpu_to_le32(0);
spin_unlock(&dq_data_lock);
dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
up_write(&dqopt->dqio_sem);
if (size != sizeof(struct v2_disk_dqinfo)) {
quota_error(sb, "Can't write info structure");
return -1;
}
return 0;
}
static void v2r0_disk2memdqb(struct dquot *dquot, void *dp)
{
struct v2r0_disk_dqblk *d = dp, empty;
struct mem_dqblk *m = &dquot->dq_dqb;
m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
m->dqb_itime = le64_to_cpu(d->dqb_itime);
m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
m->dqb_btime = le64_to_cpu(d->dqb_btime);
/* We need to escape back all-zero structure */
memset(&empty, 0, sizeof(struct v2r0_disk_dqblk));
empty.dqb_itime = cpu_to_le64(1);
if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk)))
m->dqb_itime = 0;
}
static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot)
{
struct v2r0_disk_dqblk *d = dp;
struct mem_dqblk *m = &dquot->dq_dqb;
struct qtree_mem_dqinfo *info =
sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
d->dqb_itime = cpu_to_le64(m->dqb_itime);
d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit));
d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit));
d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
d->dqb_btime = cpu_to_le64(m->dqb_btime);
d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
if (qtree_entry_unused(info, dp))
d->dqb_itime = cpu_to_le64(1);
}
static int v2r0_is_id(void *dp, struct dquot *dquot)
{
struct v2r0_disk_dqblk *d = dp;
struct qtree_mem_dqinfo *info =
sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
if (qtree_entry_unused(info, dp))
return 0;
return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
le32_to_cpu(d->dqb_id)),
dquot->dq_id);
}
static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
{
struct v2r1_disk_dqblk *d = dp, empty;
struct mem_dqblk *m = &dquot->dq_dqb;
m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
m->dqb_itime = le64_to_cpu(d->dqb_itime);
m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
m->dqb_btime = le64_to_cpu(d->dqb_btime);
/* We need to escape back all-zero structure */
memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
empty.dqb_itime = cpu_to_le64(1);
if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
m->dqb_itime = 0;
}
static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
{
struct v2r1_disk_dqblk *d = dp;
struct mem_dqblk *m = &dquot->dq_dqb;
struct qtree_mem_dqinfo *info =
sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
d->dqb_itime = cpu_to_le64(m->dqb_itime);
d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit));
d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
d->dqb_btime = cpu_to_le64(m->dqb_btime);
d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
d->dqb_pad = 0;
if (qtree_entry_unused(info, dp))
d->dqb_itime = cpu_to_le64(1);
}
static int v2r1_is_id(void *dp, struct dquot *dquot)
{
struct v2r1_disk_dqblk *d = dp;
struct qtree_mem_dqinfo *info =
sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
if (qtree_entry_unused(info, dp))
return 0;
return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
le32_to_cpu(d->dqb_id)),
dquot->dq_id);
}
static int v2_read_dquot(struct dquot *dquot)
{
struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
int ret;
down_read(&dqopt->dqio_sem);
ret = qtree_read_dquot(
sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv,
dquot);
up_read(&dqopt->dqio_sem);
return ret;
}
static int v2_write_dquot(struct dquot *dquot)
{
struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
int ret;
bool alloc = false;
/*
* If space for dquot is already allocated, we don't need any
* protection as we'll only overwrite the place of dquot. We are
* still protected by concurrent writes of the same dquot by
* dquot->dq_lock.
*/
if (!dquot->dq_off) {
alloc = true;
down_write(&dqopt->dqio_sem);
} else {
down_read(&dqopt->dqio_sem);
}
ret = qtree_write_dquot(
sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv,
dquot);
if (alloc)
up_write(&dqopt->dqio_sem);
else
up_read(&dqopt->dqio_sem);
return ret;
}
static int v2_release_dquot(struct dquot *dquot)
{
struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
int ret;
down_write(&dqopt->dqio_sem);
ret = qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot);
up_write(&dqopt->dqio_sem);
return ret;
}
static int v2_free_file_info(struct super_block *sb, int type)
{
kfree(sb_dqinfo(sb, type)->dqi_priv);
return 0;
}
static int v2_get_next_id(struct super_block *sb, struct kqid *qid)
{
struct quota_info *dqopt = sb_dqopt(sb);
int ret;
down_read(&dqopt->dqio_sem);
ret = qtree_get_next_id(sb_dqinfo(sb, qid->type)->dqi_priv, qid);
up_read(&dqopt->dqio_sem);
return ret;
}
static const struct quota_format_ops v2_format_ops = {
.check_quota_file = v2_check_quota_file,
.read_file_info = v2_read_file_info,
.write_file_info = v2_write_file_info,
.free_file_info = v2_free_file_info,
.read_dqblk = v2_read_dquot,
.commit_dqblk = v2_write_dquot,
.release_dqblk = v2_release_dquot,
.get_next_id = v2_get_next_id,
};
static struct quota_format_type v2r0_quota_format = {
.qf_fmt_id = QFMT_VFS_V0,
.qf_ops = &v2_format_ops,
.qf_owner = THIS_MODULE
};
static struct quota_format_type v2r1_quota_format = {
.qf_fmt_id = QFMT_VFS_V1,
.qf_ops = &v2_format_ops,
.qf_owner = THIS_MODULE
};
static int __init init_v2_quota_format(void)
{
int ret;
ret = register_quota_format(&v2r0_quota_format);
if (ret)
return ret;
return register_quota_format(&v2r1_quota_format);
}
static void __exit exit_v2_quota_format(void)
{
unregister_quota_format(&v2r0_quota_format);
unregister_quota_format(&v2r1_quota_format);
}
module_init(init_v2_quota_format);
module_exit(exit_v2_quota_format);