<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/testing/selftests/bpf, branch v6.7</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>Merge tag 'net-6.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net</title>
<updated>2023-12-21T17:15:37+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-12-21T17:15:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7c5e046bdcb2513f9decb3765d8bf92d604279cf'/>
<id>7c5e046bdcb2513f9decb3765d8bf92d604279cf</id>
<content type='text'>
Pull networking fixes from Paolo Abeni:
 "Including fixes from WiFi and bpf.

  Current release - regressions:

   - bpf: syzkaller found null ptr deref in unix_bpf proto add

   - eth: i40e: fix ST code value for clause 45

  Previous releases - regressions:

   - core: return error from sk_stream_wait_connect() if sk_wait_event()
     fails

   - ipv6: revert remove expired routes with a separated list of routes

   - wifi rfkill:
       - set GPIO direction
       - fix crash with WED rx support enabled

   - bluetooth:
       - fix deadlock in vhci_send_frame
       - fix use-after-free in bt_sock_recvmsg

   - eth: mlx5e: fix a race in command alloc flow

   - eth: ice: fix PF with enabled XDP going no-carrier after reset

   - eth: bnxt_en: do not map packet buffers twice

  Previous releases - always broken:

   - core:
       - check vlan filter feature in vlan_vids_add_by_dev() and
         vlan_vids_del_by_dev()
       - check dev-&gt;gso_max_size in gso_features_check()

   - mptcp: fix inconsistent state on fastopen race

   - phy: skip LED triggers on PHYs on SFP modules

   - eth: mlx5e:
       - fix double free of encap_header
       - fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list()"

* tag 'net-6.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (69 commits)
  net: check dev-&gt;gso_max_size in gso_features_check()
  kselftest: rtnetlink.sh: use grep_fail when expecting the cmd fail
  net/ipv6: Revert remove expired routes with a separated list of routes
  net: avoid build bug in skb extension length calculation
  net: ethernet: mtk_wed: fix possible NULL pointer dereference in mtk_wed_wo_queue_tx_clean()
  net: stmmac: fix incorrect flag check in timestamp interrupt
  selftests: add vlan hw filter tests
  net: check vlan filter feature in vlan_vids_add_by_dev() and vlan_vids_del_by_dev()
  net: hns3: add new maintainer for the HNS3 ethernet driver
  net: mana: select PAGE_POOL
  net: ks8851: Fix TX stall caused by TX buffer overrun
  ice: Fix PF with enabled XDP going no-carrier after reset
  ice: alter feature support check for SRIOV and LAG
  ice: stop trashing VF VSI aggregator node ID information
  mailmap: add entries for Geliang Tang
  mptcp: fill in missing MODULE_DESCRIPTION()
  mptcp: fix inconsistent state on fastopen race
  selftests: mptcp: join: fix subflow_send_ack lookup
  net: phy: skip LED triggers on PHYs on SFP modules
  bpf: Add missing BPF_LINK_TYPE invocations
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull networking fixes from Paolo Abeni:
 "Including fixes from WiFi and bpf.

  Current release - regressions:

   - bpf: syzkaller found null ptr deref in unix_bpf proto add

   - eth: i40e: fix ST code value for clause 45

  Previous releases - regressions:

   - core: return error from sk_stream_wait_connect() if sk_wait_event()
     fails

   - ipv6: revert remove expired routes with a separated list of routes

   - wifi rfkill:
       - set GPIO direction
       - fix crash with WED rx support enabled

   - bluetooth:
       - fix deadlock in vhci_send_frame
       - fix use-after-free in bt_sock_recvmsg

   - eth: mlx5e: fix a race in command alloc flow

   - eth: ice: fix PF with enabled XDP going no-carrier after reset

   - eth: bnxt_en: do not map packet buffers twice

  Previous releases - always broken:

   - core:
       - check vlan filter feature in vlan_vids_add_by_dev() and
         vlan_vids_del_by_dev()
       - check dev-&gt;gso_max_size in gso_features_check()

   - mptcp: fix inconsistent state on fastopen race

   - phy: skip LED triggers on PHYs on SFP modules

   - eth: mlx5e:
       - fix double free of encap_header
       - fix slab-out-of-bounds in mlx5_query_nic_vport_mac_list()"

* tag 'net-6.7-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (69 commits)
  net: check dev-&gt;gso_max_size in gso_features_check()
  kselftest: rtnetlink.sh: use grep_fail when expecting the cmd fail
  net/ipv6: Revert remove expired routes with a separated list of routes
  net: avoid build bug in skb extension length calculation
  net: ethernet: mtk_wed: fix possible NULL pointer dereference in mtk_wed_wo_queue_tx_clean()
  net: stmmac: fix incorrect flag check in timestamp interrupt
  selftests: add vlan hw filter tests
  net: check vlan filter feature in vlan_vids_add_by_dev() and vlan_vids_del_by_dev()
  net: hns3: add new maintainer for the HNS3 ethernet driver
  net: mana: select PAGE_POOL
  net: ks8851: Fix TX stall caused by TX buffer overrun
  ice: Fix PF with enabled XDP going no-carrier after reset
  ice: alter feature support check for SRIOV and LAG
  ice: stop trashing VF VSI aggregator node ID information
  mailmap: add entries for Geliang Tang
  mptcp: fill in missing MODULE_DESCRIPTION()
  mptcp: fix inconsistent state on fastopen race
  selftests: mptcp: join: fix subflow_send_ack lookup
  net: phy: skip LED triggers on PHYs on SFP modules
  bpf: Add missing BPF_LINK_TYPE invocations
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>cred: get rid of CONFIG_DEBUG_CREDENTIALS</title>
<updated>2023-12-15T22:19:48+00:00</updated>
<author>
<name>Jens Axboe</name>
<email>axboe@kernel.dk</email>
</author>
<published>2023-12-15T20:40:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ae1914174a63a558113e80d24ccac2773f9f7b2b'/>
<id>ae1914174a63a558113e80d24ccac2773f9f7b2b</id>
<content type='text'>
This code is rarely (never?) enabled by distros, and it hasn't caught
anything in decades. Let's kill off this legacy debug code.

Suggested-by: Linus Torvalds &lt;torvalds@linuxfoundation.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This code is rarely (never?) enabled by distros, and it hasn't caught
anything in decades. Let's kill off this legacy debug code.

Suggested-by: Linus Torvalds &lt;torvalds@linuxfoundation.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: sockmap, test for unconnected af_unix sock</title>
<updated>2023-12-14T00:33:01+00:00</updated>
<author>
<name>John Fastabend</name>
<email>john.fastabend@gmail.com</email>
</author>
<published>2023-12-01T18:01:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=50d96f05af6787a34b4eca2ee3fc1993289c4c24'/>
<id>50d96f05af6787a34b4eca2ee3fc1993289c4c24</id>
<content type='text'>
Add test to sockmap_basic to ensure af_unix sockets that are not connected
can not be added to the map. Ensure we keep DGRAM sockets working however
as these will not be connected typically.

Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Acked-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/r/20231201180139.328529-3-john.fastabend@gmail.com
Signed-off-by: Martin KaFai Lau &lt;martin.lau@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add test to sockmap_basic to ensure af_unix sockets that are not connected
can not be added to the map. Ensure we keep DGRAM sockets working however
as these will not be connected typically.

Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Acked-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/r/20231201180139.328529-3-john.fastabend@gmail.com
Signed-off-by: Martin KaFai Lau &lt;martin.lau@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/bpf: Add test for early update in prog_array_map_poke_run</title>
<updated>2023-12-06T21:40:43+00:00</updated>
<author>
<name>Jiri Olsa</name>
<email>jolsa@kernel.org</email>
</author>
<published>2023-12-06T08:30:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ffed24eff9e0e52d8e74df1c18db8ed43b4666e6'/>
<id>ffed24eff9e0e52d8e74df1c18db8ed43b4666e6</id>
<content type='text'>
Adding test that tries to trigger the BUG_IN during early map update
in prog_array_map_poke_run function.

The idea is to share prog array map between thread that constantly
updates it and another one loading a program that uses that prog
array.

Eventually we will hit a place where the program is ok to be updated
(poke-&gt;tailcall_target_stable check) but the address is still not
registered in kallsyms, so the bpf_arch_text_poke returns -EINVAL
and cause imbalance for the next tail call update check, which will
fail with -EBUSY in bpf_arch_text_poke as described in previous fix.

Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: Ilya Leoshkevich &lt;iii@linux.ibm.com&gt;
Link: https://lore.kernel.org/bpf/20231206083041.1306660-3-jolsa@kernel.org
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Adding test that tries to trigger the BUG_IN during early map update
in prog_array_map_poke_run function.

The idea is to share prog array map between thread that constantly
updates it and another one loading a program that uses that prog
array.

Eventually we will hit a place where the program is ok to be updated
(poke-&gt;tailcall_target_stable check) but the address is still not
registered in kallsyms, so the bpf_arch_text_poke returns -EINVAL
and cause imbalance for the next tail call update check, which will
fail with -EBUSY in bpf_arch_text_poke as described in previous fix.

Signed-off-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: Ilya Leoshkevich &lt;iii@linux.ibm.com&gt;
Link: https://lore.kernel.org/bpf/20231206083041.1306660-3-jolsa@kernel.org
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf, sockmap: Add af_unix test with both sockets in map</title>
<updated>2023-11-29T23:25:25+00:00</updated>
<author>
<name>John Fastabend</name>
<email>john.fastabend@gmail.com</email>
</author>
<published>2023-11-29T01:25:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=51354f700d400e55b329361e1386b04695e6e5c1'/>
<id>51354f700d400e55b329361e1386b04695e6e5c1</id>
<content type='text'>
This adds a test where both pairs of a af_unix paired socket are put into a
BPF map. This ensures that when we tear down the af_unix pair we don't have
any issues on sockmap side with ordering and reference counting.

Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20231129012557.95371-3-john.fastabend@gmail.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This adds a test where both pairs of a af_unix paired socket are put into a
BPF map. This ensures that when we tear down the af_unix pair we don't have
any issues on sockmap side with ordering and reference counting.

Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Reviewed-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/bpf/20231129012557.95371-3-john.fastabend@gmail.com
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/bpf: check if max number of bpf_loop iterations is tracked</title>
<updated>2023-11-21T02:36:40+00:00</updated>
<author>
<name>Eduard Zingerman</name>
<email>eddyz87@gmail.com</email>
</author>
<published>2023-11-21T02:07:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=57e2a52deeb12ab84c15c6d0fb93638b5b94001b'/>
<id>57e2a52deeb12ab84c15c6d0fb93638b5b94001b</id>
<content type='text'>
Check that even if bpf_loop() callback simulation does not converge to
a specific state, verification could proceed via "brute force"
simulation of maximal number of callback calls.

Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-12-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Check that even if bpf_loop() callback simulation does not converge to
a specific state, verification could proceed via "brute force"
simulation of maximal number of callback calls.

Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-12-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: keep track of max number of bpf_loop callback iterations</title>
<updated>2023-11-21T02:36:40+00:00</updated>
<author>
<name>Eduard Zingerman</name>
<email>eddyz87@gmail.com</email>
</author>
<published>2023-11-21T02:07:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bb124da69c47dd98d69361ec13244ece50bec63e'/>
<id>bb124da69c47dd98d69361ec13244ece50bec63e</id>
<content type='text'>
In some cases verifier can't infer convergence of the bpf_loop()
iteration. E.g. for the following program:

    static int cb(__u32 idx, struct num_context* ctx)
    {
        ctx-&gt;i++;
        return 0;
    }

    SEC("?raw_tp")
    int prog(void *_)
    {
        struct num_context ctx = { .i = 0 };
        __u8 choice_arr[2] = { 0, 1 };

        bpf_loop(2, cb, &amp;ctx, 0);
        return choice_arr[ctx.i];
    }

Each 'cb' simulation would eventually return to 'prog' and reach
'return choice_arr[ctx.i]' statement. At which point ctx.i would be
marked precise, thus forcing verifier to track multitude of separate
states with {.i=0}, {.i=1}, ... at bpf_loop() callback entry.

This commit allows "brute force" handling for such cases by limiting
number of callback body simulations using 'umax' value of the first
bpf_loop() parameter.

For this, extend bpf_func_state with 'callback_depth' field.
Increment this field when callback visiting state is pushed to states
traversal stack. For frame #N it's 'callback_depth' field counts how
many times callback with frame depth N+1 had been executed.
Use bpf_func_state specifically to allow independent tracking of
callback depths when multiple nested bpf_loop() calls are present.

Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-11-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In some cases verifier can't infer convergence of the bpf_loop()
iteration. E.g. for the following program:

    static int cb(__u32 idx, struct num_context* ctx)
    {
        ctx-&gt;i++;
        return 0;
    }

    SEC("?raw_tp")
    int prog(void *_)
    {
        struct num_context ctx = { .i = 0 };
        __u8 choice_arr[2] = { 0, 1 };

        bpf_loop(2, cb, &amp;ctx, 0);
        return choice_arr[ctx.i];
    }

Each 'cb' simulation would eventually return to 'prog' and reach
'return choice_arr[ctx.i]' statement. At which point ctx.i would be
marked precise, thus forcing verifier to track multitude of separate
states with {.i=0}, {.i=1}, ... at bpf_loop() callback entry.

This commit allows "brute force" handling for such cases by limiting
number of callback body simulations using 'umax' value of the first
bpf_loop() parameter.

For this, extend bpf_func_state with 'callback_depth' field.
Increment this field when callback visiting state is pushed to states
traversal stack. For frame #N it's 'callback_depth' field counts how
many times callback with frame depth N+1 had been executed.
Use bpf_func_state specifically to allow independent tracking of
callback depths when multiple nested bpf_loop() calls are present.

Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-11-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/bpf: test widening for iterating callbacks</title>
<updated>2023-11-21T02:36:40+00:00</updated>
<author>
<name>Eduard Zingerman</name>
<email>eddyz87@gmail.com</email>
</author>
<published>2023-11-21T02:06:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9f3330aa644d6d979eb064c46e85c62d4b4eac75'/>
<id>9f3330aa644d6d979eb064c46e85c62d4b4eac75</id>
<content type='text'>
A test case to verify that imprecise scalars widening is applied to
callback entering state, when callback call is simulated repeatedly.

Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-10-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
A test case to verify that imprecise scalars widening is applied to
callback entering state, when callback call is simulated repeatedly.

Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-10-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/bpf: tests for iterating callbacks</title>
<updated>2023-11-21T02:36:40+00:00</updated>
<author>
<name>Eduard Zingerman</name>
<email>eddyz87@gmail.com</email>
</author>
<published>2023-11-21T02:06:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=958465e217dbf5fc6677d42d8827fb3073d86afd'/>
<id>958465e217dbf5fc6677d42d8827fb3073d86afd</id>
<content type='text'>
A set of test cases to check behavior of callback handling logic,
check if verifier catches the following situations:
- program not safe on second callback iteration;
- program not safe on zero callback iterations;
- infinite loop inside a callback.

Verify that callback logic works for bpf_loop, bpf_for_each_map_elem,
bpf_user_ringbuf_drain, bpf_find_vma.

Acked-by: Andrii Nakryiko &lt;andrii@kernel.org&gt;
Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-8-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
A set of test cases to check behavior of callback handling logic,
check if verifier catches the following situations:
- program not safe on second callback iteration;
- program not safe on zero callback iterations;
- infinite loop inside a callback.

Verify that callback logic works for bpf_loop, bpf_for_each_map_elem,
bpf_user_ringbuf_drain, bpf_find_vma.

Acked-by: Andrii Nakryiko &lt;andrii@kernel.org&gt;
Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-8-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: verify callbacks as if they are called unknown number of times</title>
<updated>2023-11-21T02:35:44+00:00</updated>
<author>
<name>Eduard Zingerman</name>
<email>eddyz87@gmail.com</email>
</author>
<published>2023-11-21T02:06:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ab5cfac139ab8576fb54630d4cca23c3e690ee90'/>
<id>ab5cfac139ab8576fb54630d4cca23c3e690ee90</id>
<content type='text'>
Prior to this patch callbacks were handled as regular function calls,
execution of callback body was modeled exactly once.
This patch updates callbacks handling logic as follows:
- introduces a function push_callback_call() that schedules callback
  body verification in env-&gt;head stack;
- updates prepare_func_exit() to reschedule callback body verification
  upon BPF_EXIT;
- as calls to bpf_*_iter_next(), calls to callback invoking functions
  are marked as checkpoints;
- is_state_visited() is updated to stop callback based iteration when
  some identical parent state is found.

Paths with callback function invoked zero times are now verified first,
which leads to necessity to modify some selftests:
- the following negative tests required adding release/unlock/drop
  calls to avoid previously masked unrelated error reports:
  - cb_refs.c:underflow_prog
  - exceptions_fail.c:reject_rbtree_add_throw
  - exceptions_fail.c:reject_with_cp_reference
- the following precision tracking selftests needed change in expected
  log trace:
  - verifier_subprog_precision.c:callback_result_precise
    (note: r0 precision is no longer propagated inside callback and
           I think this is a correct behavior)
  - verifier_subprog_precision.c:parent_callee_saved_reg_precise_with_callback
  - verifier_subprog_precision.c:parent_stack_slot_precise_with_callback

Reported-by: Andrew Werner &lt;awerner32@gmail.com&gt;
Closes: https://lore.kernel.org/bpf/CA+vRuzPChFNXmouzGG+wsy=6eMcfr1mFG0F3g7rbg-sedGKW3w@mail.gmail.com/
Acked-by: Andrii Nakryiko &lt;andrii@kernel.org&gt;
Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-7-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
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<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Prior to this patch callbacks were handled as regular function calls,
execution of callback body was modeled exactly once.
This patch updates callbacks handling logic as follows:
- introduces a function push_callback_call() that schedules callback
  body verification in env-&gt;head stack;
- updates prepare_func_exit() to reschedule callback body verification
  upon BPF_EXIT;
- as calls to bpf_*_iter_next(), calls to callback invoking functions
  are marked as checkpoints;
- is_state_visited() is updated to stop callback based iteration when
  some identical parent state is found.

Paths with callback function invoked zero times are now verified first,
which leads to necessity to modify some selftests:
- the following negative tests required adding release/unlock/drop
  calls to avoid previously masked unrelated error reports:
  - cb_refs.c:underflow_prog
  - exceptions_fail.c:reject_rbtree_add_throw
  - exceptions_fail.c:reject_with_cp_reference
- the following precision tracking selftests needed change in expected
  log trace:
  - verifier_subprog_precision.c:callback_result_precise
    (note: r0 precision is no longer propagated inside callback and
           I think this is a correct behavior)
  - verifier_subprog_precision.c:parent_callee_saved_reg_precise_with_callback
  - verifier_subprog_precision.c:parent_stack_slot_precise_with_callback

Reported-by: Andrew Werner &lt;awerner32@gmail.com&gt;
Closes: https://lore.kernel.org/bpf/CA+vRuzPChFNXmouzGG+wsy=6eMcfr1mFG0F3g7rbg-sedGKW3w@mail.gmail.com/
Acked-by: Andrii Nakryiko &lt;andrii@kernel.org&gt;
Signed-off-by: Eduard Zingerman &lt;eddyz87@gmail.com&gt;
Link: https://lore.kernel.org/r/20231121020701.26440-7-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
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