From: Eric Dumazet edumazet@google.com
[ Upstream commit 3d3dc274ce736227e3197868ff749cff2f175f63 ]
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: 498c60153ebb ("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 Signed-off-by: Sasha Levin sashal@kernel.org --- fs/quota/quota_v2.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/fs/quota/quota_v2.c b/fs/quota/quota_v2.c index a73e5b34db418..5d4dc0f84f202 100644 --- a/fs/quota/quota_v2.c +++ b/fs/quota/quota_v2.c @@ -283,6 +283,7 @@ static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot) 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); }