BTRFS info (device loop1): using sha256 (sha256-generic) checksum algorithm
BTRFS info (device loop1): using free space tree
BTRFS info (device loop1): enabling ssd optimizations
BTRFS info (device loop1): auto enabling async discard
=====================================================
BUG: KMSAN: uninit-value in extent_fiemap+0x29cf/0x5750 fs/btrfs/extent_io.c:3252
 extent_fiemap+0x29cf/0x5750 fs/btrfs/extent_io.c:3252
 btrfs_fiemap+0x203/0x240 fs/btrfs/inode.c:7808
 ioctl_fiemap fs/ioctl.c:219 [inline]
 do_vfs_ioctl+0x2d24/0x3b10 fs/ioctl.c:810
 __do_compat_sys_ioctl fs/ioctl.c:962 [inline]
 __se_compat_sys_ioctl+0x6a6/0xfd0 fs/ioctl.c:910
 __ia32_compat_sys_ioctl+0x93/0xd0 fs/ioctl.c:910
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was stored to memory at:
 read_extent_buffer fs/btrfs/extent_io.c:4468 [inline]
 btrfs_item_key fs/btrfs/accessors.h:489 [inline]
 btrfs_item_key_to_cpu fs/btrfs/accessors.h:603 [inline]
 extent_fiemap+0x1d66/0x5750 fs/btrfs/extent_io.c:3251
 btrfs_fiemap+0x203/0x240 fs/btrfs/inode.c:7808
 ioctl_fiemap fs/ioctl.c:219 [inline]
 do_vfs_ioctl+0x2d24/0x3b10 fs/ioctl.c:810
 __do_compat_sys_ioctl fs/ioctl.c:962 [inline]
 __se_compat_sys_ioctl+0x6a6/0xfd0 fs/ioctl.c:910
 __ia32_compat_sys_ioctl+0x93/0xd0 fs/ioctl.c:910
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was created at:
 __alloc_pages+0x9a4/0xe00 mm/page_alloc.c:4791
 __alloc_pages_bulk+0x19e/0x1fa0 mm/page_alloc.c:4716
 alloc_pages_bulk_array include/linux/gfp.h:201 [inline]
 btrfs_alloc_page_array fs/btrfs/extent_io.c:844 [inline]
 btrfs_clone_extent_buffer+0x440/0x11d0 fs/btrfs/extent_io.c:3589
 fiemap_search_slot fs/btrfs/extent_io.c:2979 [inline]
 extent_fiemap+0x1a10/0x5750 fs/btrfs/extent_io.c:3226
 btrfs_fiemap+0x203/0x240 fs/btrfs/inode.c:7808
 ioctl_fiemap fs/ioctl.c:219 [inline]
 do_vfs_ioctl+0x2d24/0x3b10 fs/ioctl.c:810
 __do_compat_sys_ioctl fs/ioctl.c:962 [inline]
 __se_compat_sys_ioctl+0x6a6/0xfd0 fs/ioctl.c:910
 __ia32_compat_sys_ioctl+0x93/0xd0 fs/ioctl.c:910
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

CPU: 1 PID: 5811 Comm: syz-executor.1 Not tainted 6.4.0-rc7-syzkaller-ge6bc8833d80f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
=====================================================