FAILED: patch "[PATCH] RDMA/rxe: Fix OOB in free_rd_atomic_resources()" failed to apply to 7.2-stable tree

PATCH Applied [email protected] 3 participants 5 messages Aug 25 – Aug 27

Subsystems (3)

Stable branch InfiniBand Soft-RoCE driver (rxe)

lore

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lore

[email protected]

author maintainer

2026-08-25 11:04 UTC #0 lore raw

The patch below does not apply to the 7.2-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-7.2.y
git checkout FETCH_HEAD
git cherry-pick -x de329533792a373186d79dca1ca120f8fa0afd05
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026082516-phrase-console-29b9@gregkh' --subject-prefix 'PATCH 7.2.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From de329533792a373186d79dca1ca120f8fa0afd05 Mon Sep 17 00:00:00 2001
From: Peiyang He <[email protected]>
Date: Thu, 30 Jul 2026 10:28:27 +0800
Subject: [PATCH] RDMA/rxe: Fix OOB in free_rd_atomic_resources()

free_rd_atomic_resources() iterates using qp->attr.max_dest_rd_atomic. Updating max_dest_rd_atomic before freeing the old array can make the free path walk past the old allocation and trigger a slab out-of-bounds write catched by KASAN:
==================================================================

BUG: KASAN: slab-out-of-bounds in free_rd_atomic_resource drivers/infiniband/sw/rxe/rxe_qp.c:180 [inline]
BUG: KASAN: slab-out-of-bounds in free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:171 [inline]
BUG: KASAN: slab-out-of-bounds in free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:163 [inline]
BUG: KASAN: slab-out-of-bounds in rxe_qp_from_attr+0x1e88/0x2150 drivers/infiniband/sw/rxe/rxe_qp.c:712
Write of size 4 at addr ffff88802b8dddb8 by task syz.3.451/11063

CPU: 0 UID: 0 PID: 11063 Comm: syz.3.451 Not tainted 7.1.0 #2 PREEMPT(full)
Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x10e/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xf7/0x600 mm/kasan/report.c:482
 kasan_report+0xe4/0x120 mm/kasan/report.c:595
 free_rd_atomic_resource drivers/infiniband/sw/rxe/rxe_qp.c:180 [inline]
 free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:171 [inline]
 free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:163 [inline]
 rxe_qp_from_attr+0x1e88/0x2150 drivers/infiniband/sw/rxe/rxe_qp.c:712
 rxe_modify_qp+0x1e2/0x530 drivers/infiniband/sw/rxe/rxe_verbs.c:623
 ib_security_modify_qp+0x223/0xfa0 drivers/infiniband/core/security.c:625
 _ib_modify_qp+0x333/0xec0 drivers/infiniband/core/verbs.c:1915
 modify_qp+0x13ca/0x1940 drivers/infiniband/core/uverbs_cmd.c:1932
 ib_uverbs_modify_qp+0xcb/0x120 drivers/infiniband/core/uverbs_cmd.c:1958
 ib_uverbs_write+0xb86/0x1030 drivers/infiniband/core/uverbs_main.c:680
 vfs_write+0x2aa/0x1070 fs/read_write.c:686
 ksys_write+0x1f8/0x250 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefc75a70cd
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fefc8495018 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fefc7835fa0 RCX: 00007fefc75a70cd
RDX: 0000000000000078 RSI: 0000200000000240 RDI: 0000000000000007
RBP: 00007fefc764f10f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fefc7836038 R14: 00007fefc7835fa0 R15: 00007ffcf0586aa0
 </TASK>

Allocated by task 11063:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5296 [inline]
 __kmalloc_noprof+0x32a/0x850 mm/slub.c:5308
 kmalloc_noprof include/linux/slab.h:954 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 alloc_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:155 [inline]
 rxe_qp_from_attr+0x3f8/0x2150 drivers/infiniband/sw/rxe/rxe_qp.c:714
 rxe_modify_qp+0x1e2/0x530 drivers/infiniband/sw/rxe/rxe_verbs.c:623
 ib_security_modify_qp+0x223/0xfa0 drivers/infiniband/core/security.c:625
 _ib_modify_qp+0x333/0xec0 drivers/infiniband/core/verbs.c:1915
 modify_qp+0x13ca/0x1940 drivers/infiniband/core/uverbs_cmd.c:1932
 ib_uverbs_modify_qp+0xcb/0x120 drivers/infiniband/core/uverbs_cmd.c:1958
 ib_uverbs_write+0xb86/0x1030 drivers/infiniband/core/uverbs_main.c:680
 vfs_write+0x2aa/0x1070 fs/read_write.c:686
 ksys_write+0x1f8/0x250 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802b8ddd80
 which belongs to the cache kmalloc-64 of size 64

The buggy address is located 0 bytes to the right of
allocated 56-byte region [ffff88802b8ddd80, ffff88802b8dddb8)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b8dd
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff888015c418c0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800200020 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4651, tgid 4651 ((udev-worker)), ts 123427165316, free_ts 123425874255
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfc/0x120 mm/page_alloc.c:1853
 prep_new_page mm/page_alloc.c:1861 [inline]
 get_page_from_freelist+0x75b/0x3220 mm/page_alloc.c:3941
 __alloc_frozen_pages_noprof+0x27e/0x2b00 mm/page_alloc.c:5221
 alloc_slab_page mm/slub.c:3278 [inline]
 allocate_slab mm/slub.c:3467 [inline]
 new_slab+0xa6/0x670 mm/slub.c:3525
 refill_objects+0x278/0x420 mm/slub.c:7272
 refill_sheaf mm/slub.c:2816 [inline]
 __pcs_replace_empty_main+0x2ed/0x640 mm/slub.c:4652
 alloc_from_pcs mm/slub.c:4750 [inline]
 slab_alloc_node mm/slub.c:4884 [inline]
 __do_kmalloc_node mm/slub.c:5295 [inline]
 __kmalloc_noprof+0x68d/0x850 mm/slub.c:5308
 kmalloc_noprof include/linux/slab.h:954 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 tomoyo_encode2+0x100/0x3e0 security/tomoyo/realpath.c:45
 tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x18c/0x690 security/tomoyo/realpath.c:283
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x2ab/0x3c0 security/tomoyo/file.c:776
 tomoyo_file_open+0x6b/0x90 security/tomoyo/tomoyo.c:334
 security_file_open+0x7a/0x1b0 security/security.c:2739
 do_dentry_open+0x57e/0x1690 fs/open.c:924
 vfs_open+0x82/0x3f0 fs/open.c:1079
 do_open fs/namei.c:4699 [inline]
 path_openat+0x218a/0x3190 fs/namei.c:4858
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1397 [inline]
 __free_frozen_pages+0x763/0xfc0 mm/page_alloc.c:2938
 selinux_genfs_get_sid security/selinux/hooks.c:1364 [inline]
 inode_doinit_with_dentry+0x903/0x1320 security/selinux/hooks.c:1563
 selinux_d_instantiate+0x26/0x30 security/selinux/hooks.c:6658
 security_d_instantiate+0x123/0x190 security/security.c:3704
 d_splice_alias_ops+0x92/0x850 fs/dcache.c:3141
 kernfs_iop_lookup+0x23f/0x2d0 fs/kernfs/dir.c:1289
 lookup_open.isra.0+0x659/0x1080 fs/namei.c:4484
 open_last_lookups fs/namei.c:4611 [inline]
 path_openat+0x17dd/0x3190 fs/namei.c:4855
 do_file_open+0x20c/0x430 fs/namei.c:4887
 do_sys_openat2+0x101/0x1d0 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0x141/0x200 fs/open.c:1381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88802b8ddc80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
 ffff88802b8ddd00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88802b8ddd80: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
                                        ^
 ffff88802b8dde00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
 ffff88802b8dde80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc

Fix the OOB by moving the assignment after free_rd_atomic_resources() so the old array is freed using the old bound. This matches the original ordering in commit 8700e3e7c485 ("Soft RoCE driver").

Closes https://lore.kernel.org/all/365C68B4923F8214+30195a67-0b90-4b92-ab96-2ce41517793c@smail.nju.edu.cn/ open here

Fixes b6bbee0d2438 ("IB/rxe: Properly honor max IRD value for rd/atomic.")

Cc [email protected]

Signed-off-by Peiyang He <[email protected]>

Reviewed-by Zhu Yanjun <[email protected]>

Signed-off-by Leon Romanovsky <[email protected]>

drivers/infiniband/sw/rxe/rxe_qp.c +1 -2

index ec2cfb12559a..311f285d78a6 100644
@@ -708,8 +708,6 @@ int rxe_qp_from_attr(struct rxe_qp *qp, struct ib_qp_attr *attr, int mask,
 		int max_dest_rd_atomic = attr->max_dest_rd_atomic ?
 			roundup_pow_of_two(attr->max_dest_rd_atomic) : 0;
 
-		qp->attr.max_dest_rd_atomic = max_dest_rd_atomic;
-
 		/*
 		 * Not gated by IB_QP_STATE, so the responder task is live.
 		 * Quiesce recv_task like rxe_qp_reset() before swapping the

@@ -718,6 +716,7 @@ int rxe_qp_from_attr(struct rxe_qp *qp, struct ib_qp_attr *attr, int mask,
 		 */
 		rxe_disable_task(&qp->recv_task);
 		free_rd_atomic_resources(qp);
+		qp->attr.max_dest_rd_atomic = max_dest_rd_atomic;
 		err = alloc_rd_atomic_resources(qp, max_dest_rd_atomic);
 		/*
 		 * On ENOMEM leave recv_task quiesced: qp->resp.resources is

Zhu Yanjun

2026-08-25 14:48 UTC #1 lore raw

Hi, all

How to fix this failure? Should we make a new fix in PATCH 7.2.y?

Thanks,

Yanjun.Zhu

Quoted 204 lines · 在 2026/8/25 4:04, [email protected] 写道:

To reproduce the conflict and resubmit, you may use the following commands:

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

BUG: KASAN: slab-out-of-bounds in free_rd_atomic_resource drivers/infiniband/sw/rxe/rxe_qp.c:180 [inline]
BUG: KASAN: slab-out-of-bounds in free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:171 [inline]
BUG: KASAN: slab-out-of-bounds in free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:163 [inline]
BUG: KASAN: slab-out-of-bounds in rxe_qp_from_attr+0x1e88/0x2150 drivers/infiniband/sw/rxe/rxe_qp.c:712
Write of size 4 at addr ffff88802b8dddb8 by task syz.3.451/11063

CPU: 0 UID: 0 PID: 11063 Comm: syz.3.451 Not tainted 7.1.0 #2 PREEMPT(full)
Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
  <TASK>
  __dump_stack lib/dump_stack.c:94 [inline]
  dump_stack_lvl+0x10e/0x1f0 lib/dump_stack.c:120
  print_address_description mm/kasan/report.c:378 [inline]
  print_report+0xf7/0x600 mm/kasan/report.c:482
  kasan_report+0xe4/0x120 mm/kasan/report.c:595
  free_rd_atomic_resource drivers/infiniband/sw/rxe/rxe_qp.c:180 [inline]
  free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:171 [inline]
  free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:163 [inline]
  rxe_qp_from_attr+0x1e88/0x2150 drivers/infiniband/sw/rxe/rxe_qp.c:712
  rxe_modify_qp+0x1e2/0x530 drivers/infiniband/sw/rxe/rxe_verbs.c:623
  ib_security_modify_qp+0x223/0xfa0 drivers/infiniband/core/security.c:625
  _ib_modify_qp+0x333/0xec0 drivers/infiniband/core/verbs.c:1915
  modify_qp+0x13ca/0x1940 drivers/infiniband/core/uverbs_cmd.c:1932
  ib_uverbs_modify_qp+0xcb/0x120 drivers/infiniband/core/uverbs_cmd.c:1958
  ib_uverbs_write+0xb86/0x1030 drivers/infiniband/core/uverbs_main.c:680
  vfs_write+0x2aa/0x1070 fs/read_write.c:686
  ksys_write+0x1f8/0x250 fs/read_write.c:740
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
  entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefc75a70cd
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fefc8495018 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fefc7835fa0 RCX: 00007fefc75a70cd
RDX: 0000000000000078 RSI: 0000200000000240 RDI: 0000000000000007
RBP: 00007fefc764f10f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fefc7836038 R14: 00007fefc7835fa0 R15: 00007ffcf0586aa0
  </TASK>

Allocated by task 11063:
  kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
  kasan_save_track+0x14/0x30 mm/kasan/common.c:78
  poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
  __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
  kasan_kmalloc include/linux/kasan.h:263 [inline]
  __do_kmalloc_node mm/slub.c:5296 [inline]
  __kmalloc_noprof+0x32a/0x850 mm/slub.c:5308
  kmalloc_noprof include/linux/slab.h:954 [inline]
  kzalloc_noprof include/linux/slab.h:1188 [inline]
  alloc_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:155 [inline]
  rxe_qp_from_attr+0x3f8/0x2150 drivers/infiniband/sw/rxe/rxe_qp.c:714
  rxe_modify_qp+0x1e2/0x530 drivers/infiniband/sw/rxe/rxe_verbs.c:623
  ib_security_modify_qp+0x223/0xfa0 drivers/infiniband/core/security.c:625
  _ib_modify_qp+0x333/0xec0 drivers/infiniband/core/verbs.c:1915
  modify_qp+0x13ca/0x1940 drivers/infiniband/core/uverbs_cmd.c:1932
  ib_uverbs_modify_qp+0xcb/0x120 drivers/infiniband/core/uverbs_cmd.c:1958
  ib_uverbs_write+0xb86/0x1030 drivers/infiniband/core/uverbs_main.c:680
  vfs_write+0x2aa/0x1070 fs/read_write.c:686
  ksys_write+0x1f8/0x250 fs/read_write.c:740
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
  entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802b8ddd80
  which belongs to the cache kmalloc-64 of size 64

The buggy address is located 0 bytes to the right of
allocated 56-byte region [ffff88802b8ddd80, ffff88802b8dddb8)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b8dd
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff888015c418c0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800200020 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4651, tgid 4651 ((udev-worker)), ts 123427165316, free_ts 123425874255
  set_page_owner include/linux/page_owner.h:32 [inline]
  post_alloc_hook+0xfc/0x120 mm/page_alloc.c:1853
  prep_new_page mm/page_alloc.c:1861 [inline]
  get_page_from_freelist+0x75b/0x3220 mm/page_alloc.c:3941
  __alloc_frozen_pages_noprof+0x27e/0x2b00 mm/page_alloc.c:5221
  alloc_slab_page mm/slub.c:3278 [inline]
  allocate_slab mm/slub.c:3467 [inline]
  new_slab+0xa6/0x670 mm/slub.c:3525
  refill_objects+0x278/0x420 mm/slub.c:7272
  refill_sheaf mm/slub.c:2816 [inline]
  __pcs_replace_empty_main+0x2ed/0x640 mm/slub.c:4652
  alloc_from_pcs mm/slub.c:4750 [inline]
  slab_alloc_node mm/slub.c:4884 [inline]
  __do_kmalloc_node mm/slub.c:5295 [inline]
  __kmalloc_noprof+0x68d/0x850 mm/slub.c:5308
  kmalloc_noprof include/linux/slab.h:954 [inline]
  kzalloc_noprof include/linux/slab.h:1188 [inline]
  tomoyo_encode2+0x100/0x3e0 security/tomoyo/realpath.c:45
  tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
  tomoyo_realpath_from_path+0x18c/0x690 security/tomoyo/realpath.c:283
  tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
  tomoyo_check_open_permission+0x2ab/0x3c0 security/tomoyo/file.c:776
  tomoyo_file_open+0x6b/0x90 security/tomoyo/tomoyo.c:334
  security_file_open+0x7a/0x1b0 security/security.c:2739
  do_dentry_open+0x57e/0x1690 fs/open.c:924
  vfs_open+0x82/0x3f0 fs/open.c:1079
  do_open fs/namei.c:4699 [inline]
  path_openat+0x218a/0x3190 fs/namei.c:4858
page last free pid 1 tgid 1 stack trace:
  reset_page_owner include/linux/page_owner.h:25 [inline]
  __free_pages_prepare mm/page_alloc.c:1397 [inline]
  __free_frozen_pages+0x763/0xfc0 mm/page_alloc.c:2938
  selinux_genfs_get_sid security/selinux/hooks.c:1364 [inline]
  inode_doinit_with_dentry+0x903/0x1320 security/selinux/hooks.c:1563
  selinux_d_instantiate+0x26/0x30 security/selinux/hooks.c:6658
  security_d_instantiate+0x123/0x190 security/security.c:3704
  d_splice_alias_ops+0x92/0x850 fs/dcache.c:3141
  kernfs_iop_lookup+0x23f/0x2d0 fs/kernfs/dir.c:1289
  lookup_open.isra.0+0x659/0x1080 fs/namei.c:4484
  open_last_lookups fs/namei.c:4611 [inline]
  path_openat+0x17dd/0x3190 fs/namei.c:4855
  do_file_open+0x20c/0x430 fs/namei.c:4887
  do_sys_openat2+0x101/0x1d0 fs/open.c:1364
  do_sys_open fs/open.c:1370 [inline]
  __do_sys_openat fs/open.c:1386 [inline]
  __se_sys_openat fs/open.c:1381 [inline]
  __x64_sys_openat+0x141/0x200 fs/open.c:1381
  do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
  do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
  entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
  ffff88802b8ddc80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
  ffff88802b8ddd00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc

Quoted 1 line

ffff88802b8ddd80: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc

ffff88802b8dde00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
ffff88802b8dde80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc

Closes https://lore.kernel.org/all/365C68B4923F8214+30195a67-0b90-4b92-ab96-2ce41517793c@smail.nju.edu.cn/ open here

Fixes b6bbee0d2438 ("IB/rxe: Properly honor max IRD value for rd/atomic.")

Cc [email protected]

Signed-off-by Peiyang He <[email protected]>

Reviewed-by Zhu Yanjun <[email protected]>

Signed-off-by Leon Romanovsky <[email protected]>

drivers/infiniband/sw/rxe/rxe_qp.c +1 -2

index ec2cfb12559a..311f285d78a6 100644
@@ -708,8 +708,6 @@ int rxe_qp_from_attr(struct rxe_qp *qp, struct ib_qp_attr *attr, int mask,
  		int max_dest_rd_atomic = attr->max_dest_rd_atomic ?
  			roundup_pow_of_two(attr->max_dest_rd_atomic) : 0;
 
-		qp->attr.max_dest_rd_atomic = max_dest_rd_atomic;
-
  		/*
  		 * Not gated by IB_QP_STATE, so the responder task is live.
  		 * Quiesce recv_task like rxe_qp_reset() before swapping the

@@ -718,6 +716,7 @@ int rxe_qp_from_attr(struct rxe_qp *qp, struct ib_qp_attr *attr, int mask,
  		 */
  		rxe_disable_task(&qp->recv_task);
  		free_rd_atomic_resources(qp);
+		qp->attr.max_dest_rd_atomic = max_dest_rd_atomic;
  		err = alloc_rd_atomic_resources(qp, max_dest_rd_atomic);
  		/*
  		 * On ENOMEM leave recv_task quiesced: qp->resp.resources is

Signature · 2 lines

Best Regards,
Yanjun.Zhu

Greg KH

author maintainer

2026-08-25 15:15 UTC #2 lore raw

Quoted 3 lines · Zhu Yanjun

Hi, all
How to fix this failure? Should we make a new fix in PATCH 7.2.y?

The directions are provided here, in the email:

Quoted 8 lines

Quoted 8 lines
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-7.2.y
git checkout FETCH_HEAD
git cherry-pick -x de329533792a373186d79dca1ca120f8fa0afd05
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026082516-phrase-console-29b9@gregkh' --subject-prefix 'PATCH 7.2.y' 'HEAD^..'

Is something missing from these steps?

thanks,

greg k-h

Zhu Yanjun

2026-08-25 16:36 UTC #3 lore raw

PATCH 1/1 RDMA/rxe: Fix OOB in free_rd_atomic_resources()

In reply to [email protected]

From: Peiyang He <[email protected]>

BUG: KASAN: slab-out-of-bounds in free_rd_atomic_resource drivers/infiniband/sw/rxe/rxe_qp.c:180 [inline]
BUG: KASAN: slab-out-of-bounds in free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:171 [inline]
BUG: KASAN: slab-out-of-bounds in free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:163 [inline]
BUG: KASAN: slab-out-of-bounds in rxe_qp_from_attr+0x1e88/0x2150 drivers/infiniband/sw/rxe/rxe_qp.c:712
Write of size 4 at addr ffff88802b8dddb8 by task syz.3.451/11063

CPU: 0 UID: 0 PID: 11063 Comm: syz.3.451 Not tainted 7.1.0 #2 PREEMPT(full)
Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x10e/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xf7/0x600 mm/kasan/report.c:482
 kasan_report+0xe4/0x120 mm/kasan/report.c:595
 free_rd_atomic_resource drivers/infiniband/sw/rxe/rxe_qp.c:180 [inline]
 free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:171 [inline]
 free_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:163 [inline]
 rxe_qp_from_attr+0x1e88/0x2150 drivers/infiniband/sw/rxe/rxe_qp.c:712
 rxe_modify_qp+0x1e2/0x530 drivers/infiniband/sw/rxe/rxe_verbs.c:623
 ib_security_modify_qp+0x223/0xfa0 drivers/infiniband/core/security.c:625
 _ib_modify_qp+0x333/0xec0 drivers/infiniband/core/verbs.c:1915
 modify_qp+0x13ca/0x1940 drivers/infiniband/core/uverbs_cmd.c:1932
 ib_uverbs_modify_qp+0xcb/0x120 drivers/infiniband/core/uverbs_cmd.c:1958
 ib_uverbs_write+0xb86/0x1030 drivers/infiniband/core/uverbs_main.c:680
 vfs_write+0x2aa/0x1070 fs/read_write.c:686
 ksys_write+0x1f8/0x250 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefc75a70cd
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fefc8495018 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fefc7835fa0 RCX: 00007fefc75a70cd
RDX: 0000000000000078 RSI: 0000200000000240 RDI: 0000000000000007
RBP: 00007fefc764f10f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fefc7836038 R14: 00007fefc7835fa0 R15: 00007ffcf0586aa0
 </TASK>

Allocated by task 11063:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5296 [inline]
 __kmalloc_noprof+0x32a/0x850 mm/slub.c:5308
 kmalloc_noprof include/linux/slab.h:954 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 alloc_rd_atomic_resources drivers/infiniband/sw/rxe/rxe_qp.c:155 [inline]
 rxe_qp_from_attr+0x3f8/0x2150 drivers/infiniband/sw/rxe/rxe_qp.c:714
 rxe_modify_qp+0x1e2/0x530 drivers/infiniband/sw/rxe/rxe_verbs.c:623
 ib_security_modify_qp+0x223/0xfa0 drivers/infiniband/core/security.c:625
 _ib_modify_qp+0x333/0xec0 drivers/infiniband/core/verbs.c:1915
 modify_qp+0x13ca/0x1940 drivers/infiniband/core/uverbs_cmd.c:1932
 ib_uverbs_modify_qp+0xcb/0x120 drivers/infiniband/core/uverbs_cmd.c:1958
 ib_uverbs_write+0xb86/0x1030 drivers/infiniband/core/uverbs_main.c:680
 vfs_write+0x2aa/0x1070 fs/read_write.c:686
 ksys_write+0x1f8/0x250 fs/read_write.c:740
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88802b8ddd80
 which belongs to the cache kmalloc-64 of size 64

The buggy address is located 0 bytes to the right of
allocated 56-byte region [ffff88802b8ddd80, ffff88802b8dddb8)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b8dd
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff888015c418c0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800200020 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4651, tgid 4651 ((udev-worker)), ts 123427165316, free_ts 123425874255
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfc/0x120 mm/page_alloc.c:1853
 prep_new_page mm/page_alloc.c:1861 [inline]
 get_page_from_freelist+0x75b/0x3220 mm/page_alloc.c:3941
 __alloc_frozen_pages_noprof+0x27e/0x2b00 mm/page_alloc.c:5221
 alloc_slab_page mm/slub.c:3278 [inline]
 allocate_slab mm/slub.c:3467 [inline]
 new_slab+0xa6/0x670 mm/slub.c:3525
 refill_objects+0x278/0x420 mm/slub.c:7272
 refill_sheaf mm/slub.c:2816 [inline]
 __pcs_replace_empty_main+0x2ed/0x640 mm/slub.c:4652
 alloc_from_pcs mm/slub.c:4750 [inline]
 slab_alloc_node mm/slub.c:4884 [inline]
 __do_kmalloc_node mm/slub.c:5295 [inline]
 __kmalloc_noprof+0x68d/0x850 mm/slub.c:5308
 kmalloc_noprof include/linux/slab.h:954 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 tomoyo_encode2+0x100/0x3e0 security/tomoyo/realpath.c:45
 tomoyo_encode+0x29/0x50 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x18c/0x690 security/tomoyo/realpath.c:283
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_check_open_permission+0x2ab/0x3c0 security/tomoyo/file.c:776
 tomoyo_file_open+0x6b/0x90 security/tomoyo/tomoyo.c:334
 security_file_open+0x7a/0x1b0 security/security.c:2739
 do_dentry_open+0x57e/0x1690 fs/open.c:924
 vfs_open+0x82/0x3f0 fs/open.c:1079
 do_open fs/namei.c:4699 [inline]
 path_openat+0x218a/0x3190 fs/namei.c:4858
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1397 [inline]
 __free_frozen_pages+0x763/0xfc0 mm/page_alloc.c:2938
 selinux_genfs_get_sid security/selinux/hooks.c:1364 [inline]
 inode_doinit_with_dentry+0x903/0x1320 security/selinux/hooks.c:1563
 selinux_d_instantiate+0x26/0x30 security/selinux/hooks.c:6658
 security_d_instantiate+0x123/0x190 security/security.c:3704
 d_splice_alias_ops+0x92/0x850 fs/dcache.c:3141
 kernfs_iop_lookup+0x23f/0x2d0 fs/kernfs/dir.c:1289
 lookup_open.isra.0+0x659/0x1080 fs/namei.c:4484
 open_last_lookups fs/namei.c:4611 [inline]
 path_openat+0x17dd/0x3190 fs/namei.c:4855
 do_file_open+0x20c/0x430 fs/namei.c:4887
 do_sys_openat2+0x101/0x1d0 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0x141/0x200 fs/open.c:1381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x116/0x800 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88802b8ddc80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
 ffff88802b8ddd00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88802b8ddd80: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc
                                        ^
 ffff88802b8dde00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
 ffff88802b8dde80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc

Closes https://lore.kernel.org/all/365C68B4923F8214+30195a67-0b90-4b92-ab96-2ce41517793c@smail.nju.edu.cn/ open here

Fixes b6bbee0d2438 ("IB/rxe: Properly honor max IRD value for rd/atomic.")

Cc [email protected]

Signed-off-by Peiyang He <[email protected]>

Reviewed-by Zhu Yanjun <[email protected]>

Signed-off-by Leon Romanovsky <[email protected]>

(cherry picked from commit de329533792a373186d79dca1ca120f8fa0afd05)

[This commit is based on the upstream commit 6f7014237405 ("RDMA/rxe: Fix responder UAF on IB_QP_MAX_DEST_RD_ATOMIC modify_qp")]

Signed-off-by Zhu Yanjun <[email protected]>

---
 drivers/infiniband/sw/rxe/rxe_qp.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

drivers/infiniband/sw/rxe/rxe_qp.c +1 -3

index f3dff1aea96a..bd48ef80fa49 100644
@@ -707,10 +707,8 @@ int rxe_qp_from_attr(struct rxe_qp *qp, struct ib_qp_attr *attr, int mask,
 		int max_dest_rd_atomic = attr->max_dest_rd_atomic ?
 			roundup_pow_of_two(attr->max_dest_rd_atomic) : 0;
 
-		qp->attr.max_dest_rd_atomic = max_dest_rd_atomic;
-
 		free_rd_atomic_resources(qp);
-
+		qp->attr.max_dest_rd_atomic = max_dest_rd_atomic;
 		err = alloc_rd_atomic_resources(qp, max_dest_rd_atomic);
 		if (err)
 			return err;

Signature · 1 line

2.43.0

Sasha Levin

maintainer Applied

2026-08-27 05:18 UTC #4 lore raw

Re: [PATCH 7.2.y] RDMA/rxe: Fix OOB in free_rd_atomic_resources()

Quoted 4 lines

free_rd_atomic_resources() iterates using qp->attr.max_dest_rd_atomic. Updating max_dest_rd_atomic before freeing the old array can make the free path walk past the old allocation and trigger a slab out-of-bounds write catched by KASAN:

Queued for 7.2, 7.1, 6.18, 6.12 and 6.6, thanks.

Signature · 2 lines

Thanks,
Sasha