mirror of
https://github.com/torvalds/linux.git
synced 2026-08-01 12:11:59 +02:00
Linux kernel source tree
c3f4309693
Syzkaller reported a sleep in atomic context bug relating to the HASHCHK
handler logic:
BUG: sleeping function called from invalid context at arch/powerpc/kernel/traps.c:1518
in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 25040, name: syz-executor
preempt_count: 0, expected: 0
RCU nest depth: 0, expected: 0
no locks held by syz-executor/25040.
irq event stamp: 34
hardirqs last enabled at (33): [<c000000000048b38>] prep_irq_for_enabled_exit arch/powerpc/kernel/interrupt.c:56 [inline]
hardirqs last enabled at (33): [<c000000000048b38>] interrupt_exit_user_prepare_main+0x148/0x600 arch/powerpc/kernel/interrupt.c:230
hardirqs last disabled at (34): [<c00000000003e6a4>] interrupt_enter_prepare+0x144/0x4f0 arch/powerpc/include/asm/interrupt.h:176
softirqs last enabled at (0): [<c000000000281954>] copy_process+0x16e4/0x4750 kernel/fork.c:2436
softirqs last disabled at (0): [<0000000000000000>] 0x0
CPU: 15 PID: 25040 Comm: syz-executor Not tainted 6.5.0-rc5-00001-g3ccdff6bb06d #3
Hardware name: IBM,9105-22A POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1040.00 (NL1040_021) hv:phyp pSeries
Call Trace:
[c0000000a8247ce0] [c00000000032b0e4] __might_resched+0x3b4/0x400 kernel/sched/core.c:10189
[c0000000a8247d80] [c0000000008c7dc8] __might_fault+0xa8/0x170 mm/memory.c:5853
[c0000000a8247dc0] [c00000000004160c] do_program_check+0x32c/0xb20 arch/powerpc/kernel/traps.c:1518
[c0000000a8247e50] [c000000000009b2c] program_check_common_virt+0x3bc/0x3c0
To determine if a trap was caused by a HASHCHK instruction, we inspect
the user instruction that triggered the trap. However this may sleep
if the page needs to be faulted in (get_user_instr() reaches
__get_user(), which calls might_fault() and triggers the bug message).
Move the HASHCHK handler logic to after we allow IRQs, which is fine
because we are only interested in HASHCHK if it's a user space trap.
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.