JP Kobryn 95a4c959b9 kprobes: consistent rcu api usage for kretprobe holder ... commit d839a656d0 upstream. It seems that the pointer-to-kretprobe "rp" within the kretprobe_holder is RCU-managed, based on the (non-rethook) implementation of get_kretprobe(). The thought behind this patch is to make use of the RCU API where possible when accessing this pointer so that the needed barriers are always in place and to self-document the code. The __rcu annotation to "rp" allows for sparse RCU checking. Plain writes done to the "rp" pointer are changed to make use of the RCU macro for assignment. For the single read, the implementation of get_kretprobe() is simplified by making use of an RCU macro which accomplishes the same, but note that the log warning text will be more generic. I did find that there is a difference in assembly generated between the usage of the RCU macros vs without. For example, on arm64, when using rcu_assign_pointer(), the corresponding store instruction is a store-release (STLR) which has an implicit barrier. When normal assignment is done, a regular store (STR) is found. In the macro case, this seems to be a result of rcu_assign_pointer() using smp_store_release() when the value to write is not NULL. Link: https://lore.kernel.org/all/20231122132058.3359-1-inwardvessel@gmail.com/ Fixes: d741bf41d7 ("kprobes: Remove kretprobe hash") Cc: stable@vger.kernel.org Signed-off-by: JP Kobryn <inwardvessel@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2023-12-13 18:45:31 +01:00
..
acpi	ACPI: PM: Add acpi_device_fix_up_power_children() function	2023-12-03 07:33:07 +01:00
asm-generic	hyperv-fixes for v6.6-rc6	2023-10-10 11:01:21 -07:00
clocksource
crypto
drm	drm/atomic-helpers: Invoke end_fb_access while owning plane state	2023-12-13 18:45:25 +01:00
dt-bindings
keys
kunit
kvm	KVM: arm64: timers: Correctly handle TGE flip with CNTPOFF_EL2	2023-10-12 16:55:21 +01:00
linux	kprobes: consistent rcu api usage for kretprobe holder	2023-12-13 18:45:31 +01:00
math-emu
media	media: ipu-bridge: increase sensor_name size	2023-11-28 17:19:46 +00:00
memory
misc
net	drop_monitor: Require 'CAP_SYS_ADMIN' when joining "events" group	2023-12-13 18:45:10 +01:00
pcmcia
ras
rdma	RDMA/core: Fix umem iterator when PAGE_SIZE is greater then HCA pgsz	2023-12-13 18:45:16 +01:00
rv
scsi	scsi: sd: Fix system start for ATA devices	2023-12-08 08:52:17 +01:00
soc	firmware: tegra: Add suspend hook and reset BPMP IPC early on resume	2023-11-20 11:59:16 +01:00
sound	ASoC: soc-dai: add flag to mute and unmute stream during trigger	2023-11-28 17:20:04 +00:00
target
trace	rxrpc: Fix RTT determination to use any ACK as a source	2023-12-03 07:33:02 +01:00
uapi	uapi: propagate __struct_group() attributes to the container union	2023-12-08 08:52:22 +01:00
ufs
vdso
video	fbdev: stifb: Make the STI next font pointer a 32-bit signed offset	2023-11-28 17:19:58 +00:00
xen