This is a note to let you know that I've just added the patch titled
bpf: Force uprobe bpf program to always return 0
to the 6.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bpf-force-uprobe-bpf-program-to-always-return-0.patch
and it can be found in the queue-6.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit f21baf015f31bc28f452836b1abe5fb6d533dbf9
Author: Jiri Olsa <jolsa@xxxxxxxxxx>
Date: Fri Nov 8 14:45:33 2024 +0100
bpf: Force uprobe bpf program to always return 0
[ Upstream commit f505005bc7426f4309880da94cfbfc37efa225bd ]
As suggested by Andrii make uprobe multi bpf programs to always return 0,
so they can't force uprobe removal.
Keeping the int return type for uprobe_prog_run, because it will be used
in following session changes.
Fixes: 89ae89f53d20 ("bpf: Add multi uprobe link")
Suggested-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Acked-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Link: https://lore.kernel.org/bpf/20241108134544.480660-3-jolsa@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 630b763e52402..792dc35414a3c 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3205,7 +3205,6 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe,
struct bpf_prog *prog = link->link.prog;
bool sleepable = prog->sleepable;
struct bpf_run_ctx *old_run_ctx;
- int err = 0;
if (link->task && !same_thread_group(current, link->task))
return 0;
@@ -3218,7 +3217,7 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe,
migrate_disable();
old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
- err = bpf_prog_run(link->link.prog, regs);
+ bpf_prog_run(link->link.prog, regs);
bpf_reset_run_ctx(old_run_ctx);
migrate_enable();
@@ -3227,7 +3226,7 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe,
rcu_read_unlock_trace();
else
rcu_read_unlock();
- return err;
+ return 0;
}
static bool
