Rust symbols can become quite long due to namespacing introduced by modules, types, traits, generics, etc. For instance, the following code: pub mod my_module { pub struct MyType; pub struct MyGenericType<T>(T); pub trait MyTrait { fn my_method() -> u32; } impl MyTrait for MyGenericType<MyType> { fn my_method() -> u32 { 42 } } } generates a symbol of length 96 when using the upcoming v0 mangling scheme: _RNvXNtCshGpAVYOtgW1_7example9my_moduleINtB2_13MyGenericTypeNtB2_6MyTypeENtB2_7MyTrait9my_method At the moment, Rust symbols may reach up to 300 in length. Setting 512 as the maximum seems like a reasonable choice to keep some headroom.
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| @@ -213,7 +213,7 @@ static int klp_resolve_symbols(Elf_Shdr *sechdrs, const char *strtab, · 212 unmodified lines | |||
| 213 | * we use the smallest/strictest upper bound possible (56, based on | 213 | * we use the smallest/strictest upper bound possible (56, based on |
| 214 | * the current definition of MODULE_NAME_LEN) to prevent overflows. | 214 | * the current definition of MODULE_NAME_LEN) to prevent overflows. |
| 215 | */ | 215 | */ |
| 216 | BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 128); | 216 | BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 512); |
| 217 | 217 | ||
| 218 | relas = (Elf_Rela *) relasec->sh_addr; | 218 | relas = (Elf_Rela *) relasec->sh_addr; |
| 219 | /* For each rela in this klp relocation section */ | 219 | /* For each rela in this klp relocation section */ |
| @@ -227,7 +227,7 @@ static int klp_resolve_symbols(Elf_Shdr *sechdrs, const char *strtab, · 7 unmodified lines | |||
| 227 | 227 | ||
| 228 | /* Format: .klp.sym.sym_objname.sym_name,sympos */ | 228 | /* Format: .klp.sym.sym_objname.sym_name,sympos */ |
| 229 | cnt = sscanf(strtab + sym->st_name, | 229 | cnt = sscanf(strtab + sym->st_name, |
| 230 | ".klp.sym.%55[^.].%127[^,],%lu", | 230 | ".klp.sym.%55[^.].%511[^,],%lu", |
| 231 | sym_objname, sym_name, &sympos); | 231 | sym_objname, sym_name, &sympos); |
| 232 | if (cnt != 3) { | 232 | if (cnt != 3) { |
| 233 | pr_err("symbol %s has an incorrectly formatted name\n", | 233 | pr_err("symbol %s has an incorrectly formatted name\n", |