From 7d2cc63eca0c993c99d18893214abf8f85d566d8 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 8 Mar 2024 06:38:07 +0100 Subject: bpf: Take return from set_memory_ro() into account with bpf_prog_lock_ro() set_memory_ro() can fail, leaving memory unprotected. Check its return and take it into account as an error. Link: https://github.com/KSPP/linux/issues/7 Signed-off-by: Christophe Leroy Cc: linux-hardening@vger.kernel.org Reviewed-by: Kees Cook Message-ID: <286def78955e04382b227cb3e4b6ba272a7442e3.1709850515.git.christophe.leroy@csgroup.eu> Signed-off-by: Alexei Starovoitov --- include/linux/filter.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/linux/filter.h') diff --git a/include/linux/filter.h b/include/linux/filter.h index c99bc3df2d28..9107ee1de66f 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -887,14 +887,15 @@ bpf_ctx_narrow_access_offset(u32 off, u32 size, u32 size_default) #define bpf_classic_proglen(fprog) (fprog->len * sizeof(fprog->filter[0])) -static inline void bpf_prog_lock_ro(struct bpf_prog *fp) +static inline int __must_check bpf_prog_lock_ro(struct bpf_prog *fp) { #ifndef CONFIG_BPF_JIT_ALWAYS_ON if (!fp->jited) { set_vm_flush_reset_perms(fp); - set_memory_ro((unsigned long)fp, fp->pages); + return set_memory_ro((unsigned long)fp, fp->pages); } #endif + return 0; } static inline void bpf_jit_binary_lock_ro(struct bpf_binary_header *hdr) -- cgit v1.2.3