From c26d9f6287154774bea6dcea1cea4d1cafaed45c Mon Sep 17 00:00:00 2001 From: LeRoyce Pearson Date: Sun, 17 Jul 2022 16:01:22 -0600 Subject: [PATCH] Read dynstr starting at rpath offset Since we know the offset, we may as well read starting there. Still expects rpath to fit in 4096 bytes; that might be worth fixing in the future. Fixes issue #12112 --- lib/std/zig/system/NativeTargetInfo.zig | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/lib/std/zig/system/NativeTargetInfo.zig b/lib/std/zig/system/NativeTargetInfo.zig index fc5d833b0bb42d39a11453537a94aada210f11b7..002ad49d643d2414ed6d2c4f0717a1c8409d269d 100644 --- a/lib/std/zig/system/NativeTargetInfo.zig +++ b/lib/std/zig/system/NativeTargetInfo.zig @@ -653,12 +653,17 @@ pub fn abiAndDynamicLinkerFromFile( } else null; if (dynstr) |ds| { - const strtab_len = std.math.min(ds.size, strtab_buf.len); - const strtab_read_len = try preadMin(file, &strtab_buf, ds.offset, strtab_len); - const strtab = strtab_buf[0..strtab_read_len]; // TODO this pointer cast should not be necessary const rpoff_usize = std.math.cast(usize, rpoff) orelse return error.InvalidElfFile; - const rpath_list = mem.sliceTo(std.meta.assumeSentinel(strtab[rpoff_usize..].ptr, 0), 0); + if (rpoff_usize > ds.size) return error.InvalidElfFile; + const rpoff_file = ds.offset + rpoff_usize; + const rp_max_size = ds.size - rpoff_usize; + + const strtab_len = std.math.min(rp_max_size, strtab_buf.len); + const strtab_read_len = try preadMin(file, &strtab_buf, rpoff_file, strtab_len); + const strtab = strtab_buf[0..strtab_read_len]; + + const rpath_list = mem.sliceTo(std.meta.assumeSentinel(strtab.ptr, 0), 0); var it = mem.tokenize(u8, rpath_list, ":"); while (it.next()) |rpath| { var dir = fs.cwd().openDir(rpath, .{}) catch |err| switch (err) { -- 2.54.0