KASAN: use-after-free Read in hpfs_get_ea

Status: upstream: reported C repro on 2025/07/27 17:28
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+98d90f982e59bdb12f21@syzkaller.appspotmail.com
First crash: 363d, last: 9h00m
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/07/28 upstream (ToT) 038d61fd6422 C [report] KASAN: use-after-free Read in hpfs_get_ea
2026/07/12 upstream (ToT) 44696aa3a489 C Failed due to an error; will retry later
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: use-after-free Read in hpfs_get_ea origin:upstream 19 C 589 7h46m 364d 0/3 upstream: reported C repro on 2025/07/26 19:47
upstream KASAN: use-after-free Read in hpfs_get_ea prio:high fs 19 C error 9793 16m 373d 0/29 upstream: reported C repro on 2025/07/17 19:14
linux-6.6 KASAN: use-after-free Read in hpfs_get_ea origin:upstream 19 C error 425 14m 363d 0/2 upstream: reported C repro on 2025/07/27 17:30

Sample crash report:
hpfs: You really don't want any checks? You are crazy...
hpfs: hpfs_map_sector(): read error
hpfs: code page support is disabled
==================================================================
BUG: KASAN: use-after-free in strcmp+0xbc/0xf0 lib/string.c:361
Read of size 1 at addr ffff0000ea3598a6 by task syz.0.17/4529

CPU: 0 PID: 4529 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/02/2026
Call trace:
 dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0xfc mm/kasan/report.c:524
 __asan_report_load1_noabort+0x2c/0x38 mm/kasan/report_generic.c:348
 strcmp+0xbc/0xf0 lib/string.c:361
 hpfs_get_ea+0x100/0xa24 fs/hpfs/ea.c:139
 hpfs_read_inode+0x164/0xd18 fs/hpfs/inode.c:63
 hpfs_fill_super+0xe80/0x18a4 fs/hpfs/super.c:712
 mount_bdev+0x264/0x35c fs/super.c:1443
 hpfs_mount+0x44/0x58 fs/hpfs/super.c:758
 legacy_get_tree+0xd8/0x174 fs/fs_context.c:632
 vfs_get_tree+0x90/0x278 fs/super.c:1573
 do_new_mount+0x228/0x804 fs/namespace.c:3078
 path_mount+0x5ac/0xe6c fs/namespace.c:3408
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount fs/namespace.c:3606 [inline]
 __arm64_sys_mount+0x4a0/0x5a0 fs/namespace.c:3606
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the physical page:
page:000000003b0edb5a refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x12a359
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003b24788 fffffc0003a8d608 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000ea359780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000ea359800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000ea359880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                               ^
 ffff0000ea359900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff0000ea359980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
hpfs: hpfs_map_sector(): read error
hpfs: hpfs_map_sector(): read error
hpfs: hpfs_map_sector(): read error
hpfs: hpfs_map_sector(): read error
hpfs: hpfs_map_4sectors(): unaligned read
hpfs: hpfs_map_4sectors(): unaligned read
hpfs: filesystem error: unable to find root dir

Crashes (1177):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/20 20:30 linux-6.1.y 090666d3cc90 de6a700d .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/04/10 03:23 linux-6.1.y 1989cd3d56e2 38c8e246 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2025/12/30 09:32 linux-6.1.y 50cbba13faa2 d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2025/11/05 19:02 linux-6.1.y f6e38ae624cf a6c9c731 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2025/07/27 18:15 linux-6.1.y 3594f306da12 fb8f743d .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2025/07/27 17:46 linux-6.1.y 3594f306da12 fb8f743d .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/25 17:14 linux-6.1.y dc5c83b7f5f8 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/07/22 09:07 linux-6.1.y 090666d3cc90 b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/07/17 20:39 linux-6.1.y 090666d3cc90 8aaff637 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/07/17 15:29 linux-6.1.y 090666d3cc90 8aaff637 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/07/17 12:49 linux-6.1.y 090666d3cc90 7f27c57a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/07/06 11:29 linux-6.1.y 090666d3cc90 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/07/05 00:17 linux-6.1.y 090666d3cc90 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/06/25 18:59 linux-6.1.y fdb6fcb41cc7 7ff32d8b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/06/22 12:49 linux-6.1.y fdb6fcb41cc7 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/06/11 08:17 linux-6.1.y 228da13e907e b754d2d8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/06/10 06:47 linux-6.1.y 228da13e907e 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in hpfs_get_ea
2026/07/25 12:36 linux-6.1.y dc5c83b7f5f8 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/24 04:55 linux-6.1.y 090666d3cc90 544adce9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/23 23:45 linux-6.1.y 090666d3cc90 71a13572 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/23 07:40 linux-6.1.y 090666d3cc90 881ce5c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/22 23:08 linux-6.1.y 090666d3cc90 881ce5c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/22 10:50 linux-6.1.y 090666d3cc90 4a865b71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/22 07:33 linux-6.1.y 090666d3cc90 b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/22 05:04 linux-6.1.y 090666d3cc90 b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/20 15:55 linux-6.1.y 090666d3cc90 de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/20 10:35 linux-6.1.y 090666d3cc90 de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/18 21:02 linux-6.1.y 090666d3cc90 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/18 17:34 linux-6.1.y 090666d3cc90 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/17 03:07 linux-6.1.y 090666d3cc90 7f27c57a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/17 00:07 linux-6.1.y 090666d3cc90 71b49442 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/15 19:23 linux-6.1.y 090666d3cc90 a4ed0f4f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/14 12:34 linux-6.1.y 090666d3cc90 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/14 11:33 linux-6.1.y 090666d3cc90 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/14 11:28 linux-6.1.y 090666d3cc90 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/10 06:36 linux-6.1.y 090666d3cc90 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/06 04:50 linux-6.1.y 090666d3cc90 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/04 19:42 linux-6.1.y 090666d3cc90 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/29 04:58 linux-6.1.y fdb6fcb41cc7 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/28 01:10 linux-6.1.y fdb6fcb41cc7 fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/23 23:25 linux-6.1.y fdb6fcb41cc7 042555ff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/23 23:25 linux-6.1.y fdb6fcb41cc7 042555ff .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/23 21:34 linux-6.1.y fdb6fcb41cc7 4b1d8f01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/23 04:08 linux-6.1.y fdb6fcb41cc7 5a630be6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/21 22:48 linux-6.1.y fdb6fcb41cc7 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/20 14:25 linux-6.1.y fdb6fcb41cc7 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/13 00:25 linux-6.1.y 228da13e907e 1d2f3589 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/09 23:14 linux-6.1.y 228da13e907e 34dab4be .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/09 10:59 linux-6.1.y 228da13e907e c36c07f6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/06/08 21:35 linux-6.1.y 228da13e907e 656e94c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2025/07/27 17:27 linux-6.1.y 3594f306da12 fb8f743d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in hpfs_get_ea
2026/07/10 08:39 linux-6.1.y 090666d3cc90 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: slab-out-of-bounds Read in hpfs_get_ea
2025/10/31 23:01 linux-6.1.y f6e38ae624cf 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: out-of-bounds Read in hpfs_get_ea
* Struck through repros no longer work on HEAD.