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@palash-gandhi palash-gandhi commented Sep 15, 2023

Problem

#46 and it's side ports introduced a potential for merge conflicts in the base annotations file. If upstream changes that file, we are bound to hit a merge conflict when updating our repos because the include line is at the end of the file. Moving it to the top result in an unwanted configuration - where upstream's annotations overrides Delphix's annotations. We want Delphix's annotations to be processed at the very end.

Solution

delphix/linux-pkg#300 moves Delphix's custom annotations file into the linux-pkg repo. This change modifies the kernel repo to remove it.

Testing Done

See delphix/linux-pkg#300 for testing.

@palash-gandhi palash-gandhi force-pushed the dlpx/pr/palash-delphix/960afe41-2f10-437d-8484-15cbf6a3e388 branch from a9fdbe7 to 3c3b4ff Compare September 15, 2023 01:11
@palash-gandhi palash-gandhi marked this pull request as ready for review September 15, 2023 01:16
@palash-gandhi palash-gandhi merged commit b96bbd3 into develop Sep 19, 2023
@palash-gandhi palash-gandhi deleted the dlpx/pr/palash-delphix/960afe41-2f10-437d-8484-15cbf6a3e388 branch September 19, 2023 15:03
delphix-devops-bot pushed a commit that referenced this pull request Mar 29, 2025
BugLink: https://bugs.launchpad.net/bugs/2089272

[ Upstream commit 60f07e2 ]

We use uprobe in aarch64_be, which we found the tracee task would exit
due to SIGILL when we enable the uprobe trace.
We can see the replace inst from uprobe is not correct in aarch big-endian.
As in Armv8-A, instruction fetches are always treated as little-endian,
we should treat the UPROBE_SWBP_INSN as little-endian。

The test case is as following。
bash-4.4# ./mqueue_test_aarchbe 1 1 2 1 10 > /dev/null &
bash-4.4# cd /sys/kernel/debug/tracing/
bash-4.4# echo 'p:test /mqueue_test_aarchbe:0xc30 %x0 %x1' > uprobe_events
bash-4.4# echo 1 > events/uprobes/enable
bash-4.4#
bash-4.4# ps
  PID TTY          TIME CMD
  140 ?        00:00:01 bash
  237 ?        00:00:00 ps
[1]+  Illegal instruction     ./mqueue_test_aarchbe 1 1 2 1 100 > /dev/null

which we debug use gdb as following:

bash-4.4# gdb attach 155
(gdb) disassemble send
Dump of assembler code for function send:
   0x0000000000400c30 <+0>:     .inst   0xa00020d4 ; undefined
   0x0000000000400c34 <+4>:     mov     x29, sp
   0x0000000000400c38 <+8>:     str     w0, [sp, #28]
   0x0000000000400c3c <+12>:    strb    w1, [sp, #27]
   0x0000000000400c40 <+16>:    str     xzr, [sp, #40]
   0x0000000000400c44 <+20>:    str     xzr, [sp, #48]
   0x0000000000400c48 <+24>:    add     x0, sp, #0x1b
   0x0000000000400c4c <+28>:    mov     w3, #0x0                 // #0
   0x0000000000400c50 <+32>:    mov     x2, #0x1                 // #1
   0x0000000000400c54 <+36>:    mov     x1, x0
   0x0000000000400c58 <+40>:    ldr     w0, [sp, #28]
   0x0000000000400c5c <+44>:    bl      0x405e10 <mq_send>
   0x0000000000400c60 <+48>:    str     w0, [sp, #60]
   0x0000000000400c64 <+52>:    ldr     w0, [sp, #60]
   0x0000000000400c68 <+56>:    ldp     x29, x30, [sp], #64
   0x0000000000400c6c <+60>:    ret
End of assembler dump.
(gdb) info b
No breakpoints or watchpoints.
(gdb) c
Continuing.

Program received signal SIGILL, Illegal instruction.
0x0000000000400c30 in send ()
(gdb) x/10x 0x400c30
0x400c30 <send>:    0xd42000a0   0xfd030091      0xe01f00b9      0xe16f0039
0x400c40 <send+16>: 0xff1700f9   0xff1b00f9      0xe06f0091      0x03008052
0x400c50 <send+32>: 0x220080d2   0xe10300aa
(gdb) disassemble 0x400c30
Dump of assembler code for function send:
=> 0x0000000000400c30 <+0>:     .inst   0xa00020d4 ; undefined
   0x0000000000400c34 <+4>:     mov     x29, sp
   0x0000000000400c38 <+8>:     str     w0, [sp, #28]
   0x0000000000400c3c <+12>:    strb    w1, [sp, #27]
   0x0000000000400c40 <+16>:    str     xzr, [sp, #40]

Signed-off-by: junhua huang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>
Stable-dep-of: 13f8f1e ("arm64: probes: Fix uprobes for big-endian kernels")
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Manuel Diewald <[email protected]>
Signed-off-by: Mehmet Basaran <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Mar 29, 2025
commit 86e6ca5 upstream.

blkcg_unpin_online() walks up the blkcg hierarchy putting the online pin. To
walk up, it uses blkcg_parent(blkcg) but it was calling that after
blkcg_destroy_blkgs(blkcg) which could free the blkcg, leading to the
following UAF:

  ==================================================================
  BUG: KASAN: slab-use-after-free in blkcg_unpin_online+0x15a/0x270
  Read of size 8 at addr ffff8881057678c0 by task kworker/9:1/117

  CPU: 9 UID: 0 PID: 117 Comm: kworker/9:1 Not tainted 6.13.0-rc1-work-00182-gb8f52214c61a-dirty #48
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS unknown 02/02/2022
  Workqueue: cgwb_release cgwb_release_workfn
  Call Trace:
   <TASK>
   dump_stack_lvl+0x27/0x80
   print_report+0x151/0x710
   kasan_report+0xc0/0x100
   blkcg_unpin_online+0x15a/0x270
   cgwb_release_workfn+0x194/0x480
   process_scheduled_works+0x71b/0xe20
   worker_thread+0x82a/0xbd0
   kthread+0x242/0x2c0
   ret_from_fork+0x33/0x70
   ret_from_fork_asm+0x1a/0x30
   </TASK>
  ...
  Freed by task 1944:
   kasan_save_track+0x2b/0x70
   kasan_save_free_info+0x3c/0x50
   __kasan_slab_free+0x33/0x50
   kfree+0x10c/0x330
   css_free_rwork_fn+0xe6/0xb30
   process_scheduled_works+0x71b/0xe20
   worker_thread+0x82a/0xbd0
   kthread+0x242/0x2c0
   ret_from_fork+0x33/0x70
   ret_from_fork_asm+0x1a/0x30

Note that the UAF is not easy to trigger as the free path is indirected
behind a couple RCU grace periods and a work item execution. I could only
trigger it with artifical msleep() injected in blkcg_unpin_online().

Fix it by reading the parent pointer before destroying the blkcg's blkg's.

Signed-off-by: Tejun Heo <[email protected]>
Reported-by: Abagail ren <[email protected]>
Suggested-by: Linus Torvalds <[email protected]>
Fixes: 4308a43 ("blkcg: don't offline parent blkcg first")
Cc: [email protected] # v5.7+
Signed-off-by: Jens Axboe <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
CVE-2024-56672
Signed-off-by: Noah Wager <[email protected]>
Signed-off-by: Koichiro Den <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Apr 2, 2025
blkcg_unpin_online() walks up the blkcg hierarchy putting the online pin. To
walk up, it uses blkcg_parent(blkcg) but it was calling that after
blkcg_destroy_blkgs(blkcg) which could free the blkcg, leading to the
following UAF:

  ==================================================================
  BUG: KASAN: slab-use-after-free in blkcg_unpin_online+0x15a/0x270
  Read of size 8 at addr ffff8881057678c0 by task kworker/9:1/117

  CPU: 9 UID: 0 PID: 117 Comm: kworker/9:1 Not tainted 6.13.0-rc1-work-00182-gb8f52214c61a-dirty #48
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS unknown 02/02/2022
  Workqueue: cgwb_release cgwb_release_workfn
  Call Trace:
   <TASK>
   dump_stack_lvl+0x27/0x80
   print_report+0x151/0x710
   kasan_report+0xc0/0x100
   blkcg_unpin_online+0x15a/0x270
   cgwb_release_workfn+0x194/0x480
   process_scheduled_works+0x71b/0xe20
   worker_thread+0x82a/0xbd0
   kthread+0x242/0x2c0
   ret_from_fork+0x33/0x70
   ret_from_fork_asm+0x1a/0x30
   </TASK>
  ...
  Freed by task 1944:
   kasan_save_track+0x2b/0x70
   kasan_save_free_info+0x3c/0x50
   __kasan_slab_free+0x33/0x50
   kfree+0x10c/0x330
   css_free_rwork_fn+0xe6/0xb30
   process_scheduled_works+0x71b/0xe20
   worker_thread+0x82a/0xbd0
   kthread+0x242/0x2c0
   ret_from_fork+0x33/0x70
   ret_from_fork_asm+0x1a/0x30

Note that the UAF is not easy to trigger as the free path is indirected
behind a couple RCU grace periods and a work item execution. I could only
trigger it with artifical msleep() injected in blkcg_unpin_online().

Fix it by reading the parent pointer before destroying the blkcg's blkg's.

Signed-off-by: Tejun Heo <[email protected]>
Reported-by: Abagail ren <[email protected]>
Suggested-by: Linus Torvalds <[email protected]>
Fixes: 4308a43 ("blkcg: don't offline parent blkcg first")
Cc: [email protected] # v5.7+
Signed-off-by: Jens Axboe <[email protected]>

CVE-2024-56672
(cherry picked from commit 86e6ca5)
Signed-off-by: Massimiliano Pellizzer <[email protected]>
Acked-by: Koichiro Den <[email protected]>
Acked-by: Stewart Hore <[email protected]>
Signed-off-by: Koichiro Den <[email protected]>
delphix-devops-bot pushed a commit that referenced this pull request Sep 9, 2025
… prevent wrong idmap generation

BugLink: https://bugs.launchpad.net/bugs/2115252

commit 363cd2b81cfdf706bbfc9ec78db000c9b1ecc552 upstream.

The PTE_MAYBE_NG macro sets the nG page table bit according to the value
of "arm64_use_ng_mappings". This variable is currently placed in the
.bss section. create_init_idmap() is called before the .bss section
initialisation which is done in early_map_kernel(). Therefore,
data/test_prot in create_init_idmap() could be set incorrectly through
the PAGE_KERNEL -> PROT_DEFAULT -> PTE_MAYBE_NG macros.

   # llvm-objdump-21 --syms vmlinux-gcc | grep arm64_use_ng_mappings
     ffff800082f242a8 g     O .bss    0000000000000001 arm64_use_ng_mappings

The create_init_idmap() function disassembly compiled with llvm-21:

  // create_init_idmap()
  ffff80008255c058: d10103ff     	sub	sp, sp, #0x40
  ffff80008255c05c: a9017bfd     	stp	x29, x30, [sp, #0x10]
  ffff80008255c060: a90257f6     	stp	x22, x21, [sp, #0x20]
  ffff80008255c064: a9034ff4     	stp	x20, x19, [sp, #0x30]
  ffff80008255c068: 910043fd     	add	x29, sp, #0x10
  ffff80008255c06c: 90003fc8     	adrp	x8, 0xffff800082d54000
  ffff80008255c070: d280e06a     	mov	x10, #0x703     // =1795
  ffff80008255c074: 91400409     	add	x9, x0, #0x1, lsl #12 // =0x1000
  ffff80008255c078: 394a4108     	ldrb	w8, [x8, #0x290] ------------- (1)
  ffff80008255c07c: f2e00d0a     	movk	x10, #0x68, lsl #48
  ffff80008255c080: f90007e9     	str	x9, [sp, #0x8]
  ffff80008255c084: aa0103f3     	mov	x19, x1
  ffff80008255c088: aa0003f4     	mov	x20, x0
  ffff80008255c08c: 14000000     	b	0xffff80008255c08c <__pi_create_init_idmap+0x34>
  ffff80008255c090: aa082d56     	orr	x22, x10, x8, lsl #11 -------- (2)

Note (1) is loading the arm64_use_ng_mappings value in w8 and (2) is set
the text or data prot with the w8 value to set PTE_NG bit. If the .bss
section isn't initialized, x8 could include a garbage value and generate
an incorrect mapping.

Annotate arm64_use_ng_mappings as __read_mostly so that it is placed in
the .data section.

Fixes: 84b04d3 ("arm64: kernel: Create initial ID map from C code")
Cc: [email protected] # 6.9.x
Tested-by: Nathan Chancellor <[email protected]>
Signed-off-by: Yeoreum Yun <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[[email protected]: use __read_mostly instead of __ro_after_init]
[[email protected]: slight tweaking of the code comment]
Signed-off-by: Catalin Marinas <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Manuel Diewald <[email protected]>
Signed-off-by: Stefan Bader <[email protected]>
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