linux/include
Eduard Zingerman 2a0992829e bpf: correct loop detection for iterators convergence
It turns out that .branches > 0 in is_state_visited() is not a
sufficient condition to identify if two verifier states form a loop
when iterators convergence is computed. This commit adds logic to
distinguish situations like below:

 (I)            initial       (II)            initial
                  |                             |
                  V                             V
     .---------> hdr                           ..
     |            |                             |
     |            V                             V
     |    .------...                    .------..
     |    |       |                     |       |
     |    V       V                     V       V
     |   ...     ...               .-> hdr     ..
     |    |       |                |    |       |
     |    V       V                |    V       V
     |   succ <- cur               |   succ <- cur
     |    |                        |    |
     |    V                        |    V
     |   ...                       |   ...
     |    |                        |    |
     '----'                        '----'

For both (I) and (II) successor 'succ' of the current state 'cur' was
previously explored and has branches count at 0. However, loop entry
'hdr' corresponding to 'succ' might be a part of current DFS path.
If that is the case 'succ' and 'cur' are members of the same loop
and have to be compared exactly.

Co-developed-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Co-developed-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Reviewed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20231024000917.12153-6-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-10-23 21:49:32 -07:00
..
acpi
asm-generic hyperv-fixes for v6.6-rc6 2023-10-10 11:01:21 -07:00
clocksource
crypto
drm drm/tests: helpers: Avoid a driver uaf 2023-09-14 13:57:58 +02:00
dt-bindings IOMMU Updates for Linux v6.6 2023-09-01 16:54:25 -07:00
keys
kunit - An extensive rework of kexec and crash Kconfig from Eric DeVolder 2023-08-29 14:53:51 -07:00
kvm
linux bpf: correct loop detection for iterators convergence 2023-10-23 21:49:32 -07:00
math-emu
media media updates for v6.6-rc1 2023-09-01 12:21:32 -07:00
memory
misc
net bpf, tcx: Get rid of tcx_link_const 2023-10-23 15:01:53 -07:00
pcmcia
ras
rdma
rv rv: Set variable 'da_mon_##name' to static 2023-09-01 21:00:00 -04:00
scsi ATA fixes for 6.6-rc4 2023-09-29 13:38:34 -07:00
soc IOMMU Updates for Linux v6.6 2023-09-01 16:54:25 -07:00
sound ASoC: core: Do not call link_exit() on uninitialized rtd objects 2023-09-29 14:17:49 +02:00
target
trace net: implement lockless SO_MAX_PACING_RATE 2023-10-01 19:09:54 +01:00
uapi bpf-next-for-netdev 2023-10-16 21:05:33 -07:00
ufs Merge branch 'fixes' into misc 2023-09-02 08:25:19 +01:00
vdso
video
xen arm/xen: remove lazy mode related definitions 2023-09-19 07:04:49 +02:00