Ksawlii/kernel_samsung_a53x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

bpf: use kvzmalloc to allocate BPF verifier environment

Browse source 
[ Upstream commit 434247637c66e1be2bc71a9987d4c3f0d8672387 ]

The kzmalloc call in bpf_check can fail when memory is very fragmented,
which in turn can lead to an OOM kill.

Use kvzmalloc to fall back to vmalloc when memory is too fragmented to
allocate an order 3 sized bpf verifier environment.

Admittedly this is not a very common case, and only happens on systems
where memory has already been squeezed close to the limit, but this does
not seem like much of a hot path, and it's a simple enough fix.

Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Link: https://lore.kernel.org/r/20241008170735.16766766@imladris.surriel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Rik van Riel 2024-10-08 17:07:35 -04:00 committed by Kreciorek
parent 04082543f0
commit 2a2e1902e3
1 changed files with 2 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
kernel/bpf/verifier.c
View file

@ -12582,7 +12582,7 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr,
/* 'struct bpf_verifier_env' can be global, but since it's not small, /* 'struct bpf_verifier_env' can be global, but since it's not small,
* allocate/free it every time bpf_check() is called * allocate/free it every time bpf_check() is called
*/ */
env = kzalloc(sizeof(struct bpf_verifier_env), GFP_KERNEL); env = kvzalloc(sizeof(struct bpf_verifier_env), GFP_KERNEL);
if (!env) if (!env)
return -ENOMEM; return -ENOMEM;
log = &env->log; log = &env->log;
@ -12773,6 +12773,6 @@ err_unlock:
mutex_unlock(&bpf_verifier_lock); mutex_unlock(&bpf_verifier_lock);
vfree(env->insn_aux_data); vfree(env->insn_aux_data);
err_free_env: err_free_env:
kfree(env); kvfree(env);
return ret; return ret;
} }