From: Alexey Dobriyan <adobriyan@gmail.com> mainline inclusion from mainline-v5.19-rc1 commit 391e982bfa632b8315235d8be9c0a81374c6a19c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBP43S CVE: CVE-2022-49444 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- It is trivial to craft a module to trigger OOB access in this line: if (info->secstrings[strhdr->sh_size - 1] != '\0') { BUG: unable to handle page fault for address: ffffc90000aa0fff PGD 100000067 P4D 100000067 PUD 100066067 PMD 10436f067 PTE 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 7 PID: 1215 Comm: insmod Not tainted 5.18.0-rc5-00007-g9bf578647087-dirty #10 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:load_module+0x19b/0x2391 Fixes: ec2a29593c83 ("module: harden ELF info handling") Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> [rebased patch onto modules-next] Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Conflicts: kernel/module/main.c kernel/module.c [context conflict] Signed-off-by: Xiangwei Li <liwei728@huawei.com> --- kernel/module.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/module.c b/kernel/module.c index e978debc93df..57b34c32a916 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -3053,6 +3053,10 @@ static int elf_validity_check(struct load_info *info) * strings in the section safe. */ info->secstrings = (void *)info->hdr + strhdr->sh_offset; + if (strhdr->sh_size == 0) { + pr_err("empty section name table\n"); + return -ENOEXEC; + } if (info->secstrings[strhdr->sh_size - 1] != '\0') return -ENOEXEC; -- 2.25.1