[syzbot] [fs?] memory leak in getname_flags

[syzbot] [fs?] memory leak in getname_flags

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    b927546677c8 Merge tag 'dma-mapping-6.19-2025-12-22' of gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=146fef1a580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d60836e327fd6756
dashboard link: https://syzkaller.appspot.com/bug?extid=00e61c43eb5e4740438f
compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=153e90fc580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=126fef1a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7c1254aadd0a/disk-b9275466.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/15b98aa2b078/vmlinux-b9275466.xz
kernel image: https://storage.googleapis.com/syzbot-assets/10a68a086ef8/bzImage-b9275466.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+00e61c43eb5e4740438f@syzkaller.appspotmail.com

2025/12/24 09:11:05 executed programs: 5
BUG: memory leak
unreferenced object 0xffff8881098a2000 (size 4096):
  comm "syz.0.17", pid 6087, jiffies 4294944491
  hex dump (first 32 bytes):
    20 20 8a 09 81 88 ff ff 40 02 00 00 00 20 00 00    ......@.... ..
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc 5d427fb2):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4958 [inline]
    slab_alloc_node mm/slub.c:5263 [inline]
    kmem_cache_alloc_noprof+0x3b4/0x590 mm/slub.c:5270
    getname_flags.part.0+0x26/0x280 fs/namei.c:146
    getname_flags+0x4b/0x90 include/linux/audit.h:345
    getname include/linux/fs.h:2498 [inline]
    __io_openat_prep+0x87/0x1a0 io_uring/openclose.c:70
    io_init_req io_uring/io_uring.c:2234 [inline]
    io_submit_sqe io_uring/io_uring.c:2281 [inline]
    io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2434
    __do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3280
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object 0xffff8881009ea000 (size 4096):
  comm "syz.0.18", pid 6090, jiffies 4294944493
  hex dump (first 32 bytes):
    20 a0 9e 00 81 88 ff ff 40 02 00 00 00 20 00 00   .......@.... ..
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc 254b05b2):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4958 [inline]
    slab_alloc_node mm/slub.c:5263 [inline]
    kmem_cache_alloc_noprof+0x3b4/0x590 mm/slub.c:5270
    getname_flags.part.0+0x26/0x280 fs/namei.c:146
    getname_flags+0x4b/0x90 include/linux/audit.h:345
    getname include/linux/fs.h:2498 [inline]
    __io_openat_prep+0x87/0x1a0 io_uring/openclose.c:70
    io_init_req io_uring/io_uring.c:2234 [inline]
    io_submit_sqe io_uring/io_uring.c:2281 [inline]
    io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2434
    __do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3280
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object 0xffff8881009eb000 (size 4096):
  comm "syz.0.19", pid 6092, jiffies 4294944494
  hex dump (first 32 bytes):
    20 b0 9e 00 81 88 ff ff 40 02 00 00 00 20 00 00   .......@.... ..
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc 9f4244d8):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4958 [inline]
    slab_alloc_node mm/slub.c:5263 [inline]
    kmem_cache_alloc_noprof+0x3b4/0x590 mm/slub.c:5270
    getname_flags.part.0+0x26/0x280 fs/namei.c:146
    getname_flags+0x4b/0x90 include/linux/audit.h:345
    getname include/linux/fs.h:2498 [inline]
    __io_openat_prep+0x87/0x1a0 io_uring/openclose.c:70
    io_init_req io_uring/io_uring.c:2234 [inline]
    io_submit_sqe io_uring/io_uring.c:2281 [inline]
    io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2434
    __do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3280
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object 0xffff8881098a6000 (size 4096):
  comm "syz.0.20", pid 6134, jiffies 4294945094
  hex dump (first 32 bytes):
    20 60 8a 09 81 88 ff ff 40 02 00 00 00 20 00 00   `......@.... ..
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc d8f470d9):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4958 [inline]
    slab_alloc_node mm/slub.c:5263 [inline]
    kmem_cache_alloc_noprof+0x3b4/0x590 mm/slub.c:5270
    getname_flags.part.0+0x26/0x280 fs/namei.c:146
    getname_flags+0x4b/0x90 include/linux/audit.h:345
    getname include/linux/fs.h:2498 [inline]
    __io_openat_prep+0x87/0x1a0 io_uring/openclose.c:70
    io_init_req io_uring/io_uring.c:2234 [inline]
    io_submit_sqe io_uring/io_uring.c:2281 [inline]
    io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2434
    __do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3280
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f

BUG: memory leak
unreferenced object 0xffff8881098a1000 (size 4096):
  comm "syz.0.21", pid 6135, jiffies 4294945095
  hex dump (first 32 bytes):
    20 10 8a 09 81 88 ff ff 40 02 00 00 00 20 00 00   .......@.... ..
    01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc 4828ba4d):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4958 [inline]
    slab_alloc_node mm/slub.c:5263 [inline]
    kmem_cache_alloc_noprof+0x3b4/0x590 mm/slub.c:5270
    getname_flags.part.0+0x26/0x280 fs/namei.c:146
    getname_flags+0x4b/0x90 include/linux/audit.h:345
    getname include/linux/fs.h:2498 [inline]
    __io_openat_prep+0x87/0x1a0 io_uring/openclose.c:70
    io_init_req io_uring/io_uring.c:2234 [inline]
    io_submit_sqe io_uring/io_uring.c:2281 [inline]
    io_submit_sqes+0x40d/0xf40 io_uring/io_uring.c:2434
    __do_sys_io_uring_enter+0x841/0xcf0 io_uring/io_uring.c:3280
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xa4/0xf80 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f

connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF


---
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If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
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If you want to undo deduplication, reply with:
#syz undup

[PATCH] io_uring: Fix filename leak in __io_openat_prep

[Prithvi Tambewagh]

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git b927546677c876e26eba308550207c2ddf812a43

Signed-off-by: Prithvi Tambewagh <activprithvi@gmail.com>
---
 io_uring/openclose.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/io_uring/openclose.c b/io_uring/openclose.c
index bfeb91b31bba..fc190a3d8112 100644
--- a/io_uring/openclose.c
+++ b/io_uring/openclose.c
@@ -75,8 +75,11 @@ static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe
 	}
 
 	open->file_slot = READ_ONCE(sqe->file_index);
-	if (open->file_slot && (open->how.flags & O_CLOEXEC))
+	if (open->file_slot && (open->how.flags & O_CLOEXEC)) {
+		putname(open->filename);
+		open->filename = NULL;
 		return -EINVAL;
+	}
 
 	open->nofile = rlimit(RLIMIT_NOFILE);
 	req->flags |= REQ_F_NEED_CLEANUP;

base-commit: b927546677c876e26eba308550207c2ddf812a43
-- 
2.34.1

Re: [syzbot] [fs?] memory leak in getname_flags

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+00e61c43eb5e4740438f@syzkaller.appspotmail.com
Tested-by: syzbot+00e61c43eb5e4740438f@syzkaller.appspotmail.com

Tested on:

commit:         b9275466 Merge tag 'dma-mapping-6.19-2025-12-22' of gi..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=170e209a580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d60836e327fd6756
dashboard link: https://syzkaller.appspot.com/bug?extid=00e61c43eb5e4740438f
compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=11e790fc580000

Note: testing is done by a robot and is best-effort only.

Syzbot test for v2: io_uring: fix filename leak in __io_openat_prep()

[Prithvi Tambewagh]

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git b927546677c876e26eba308550207c2ddf812a43

Signed-off-by: Prithvi Tambewagh <activprithvi@gmail.com>
---
 io_uring/openclose.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/io_uring/openclose.c b/io_uring/openclose.c
index bfeb91b31bba..15dde9bd6ff6 100644
--- a/io_uring/openclose.c
+++ b/io_uring/openclose.c
@@ -73,13 +73,13 @@ static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe
 		open->filename = NULL;
 		return ret;
 	}
+	req->flags |= REQ_F_NEED_CLEANUP;
 
 	open->file_slot = READ_ONCE(sqe->file_index);
 	if (open->file_slot && (open->how.flags & O_CLOEXEC))
 		return -EINVAL;
 
 	open->nofile = rlimit(RLIMIT_NOFILE);
-	req->flags |= REQ_F_NEED_CLEANUP;
 	if (io_openat_force_async(open))
 		req->flags |= REQ_F_FORCE_ASYNC;
 	return 0;

base-commit: b927546677c876e26eba308550207c2ddf812a43
-- 
2.34.1

Re: [syzbot] [fs?] memory leak in getname_flags

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+00e61c43eb5e4740438f@syzkaller.appspotmail.com
Tested-by: syzbot+00e61c43eb5e4740438f@syzkaller.appspotmail.com

Tested on:

commit:         b9275466 Merge tag 'dma-mapping-6.19-2025-12-22' of gi..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=17332bb4580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d60836e327fd6756
dashboard link: https://syzkaller.appspot.com/bug?extid=00e61c43eb5e4740438f
compiler:       gcc (Debian 12.2.0-14+deb12u1) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1640c8fc580000

Note: testing is done by a robot and is best-effort only.