diff options
Diffstat (limited to 'arch/x86/kernel/unwind_frame.c')
| -rw-r--r-- | arch/x86/kernel/unwind_frame.c | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/arch/x86/kernel/unwind_frame.c b/arch/x86/kernel/unwind_frame.c index a224b5ab103f..d8ba93778ae3 100644 --- a/arch/x86/kernel/unwind_frame.c +++ b/arch/x86/kernel/unwind_frame.c @@ -74,13 +74,7 @@ static bool in_entry_code(unsigned long ip) { char *addr = (char *)ip; - if (addr >= __entry_text_start && addr < __entry_text_end) - return true; - - if (addr >= __irqentry_text_start && addr < __irqentry_text_end) - return true; - - return false; + return addr >= __entry_text_start && addr < __entry_text_end; } static inline unsigned long *last_frame(struct unwind_state *state) @@ -189,6 +183,16 @@ static struct pt_regs *decode_frame_pointer(unsigned long *bp) } #endif +/* + * While walking the stack, KMSAN may stomp on stale locals from other + * functions that were marked as uninitialized upon function exit, and + * now hold the call frame information for the current function (e.g. the frame + * pointer). Because KMSAN does not specifically mark call frames as + * initialized, false positive reports are possible. To prevent such reports, + * we mark the functions scanning the stack (here and below) with + * __no_kmsan_checks. + */ +__no_kmsan_checks static bool update_stack_state(struct unwind_state *state, unsigned long *next_bp) { @@ -246,8 +250,7 @@ static bool update_stack_state(struct unwind_state *state, else { addr_p = unwind_get_return_address_ptr(state); addr = READ_ONCE_TASK_STACK(state->task, *addr_p); - state->ip = ftrace_graph_ret_addr(state->task, &state->graph_idx, - addr, addr_p); + state->ip = unwind_recover_ret_addr(state, addr, addr_p); } /* Save the original stack pointer for unwind_dump(): */ @@ -257,6 +260,7 @@ static bool update_stack_state(struct unwind_state *state, return true; } +__no_kmsan_checks bool unwind_next_frame(struct unwind_state *state) { struct pt_regs *regs; @@ -275,13 +279,13 @@ bool unwind_next_frame(struct unwind_state *state) /* * kthreads (other than the boot CPU's idle thread) have some * partial regs at the end of their stack which were placed - * there by copy_thread_tls(). But the regs don't have any + * there by copy_thread(). But the regs don't have any * useful information, so we can skip them. * * This user_mode() check is slightly broader than a PF_KTHREAD * check because it also catches the awkward situation where a * newly forked kthread transitions into a user task by calling - * do_execve(), which eventually clears PF_KTHREAD. + * kernel_execve(), which eventually clears PF_KTHREAD. */ if (!user_mode(regs)) goto the_end; @@ -344,6 +348,9 @@ bad_address: if (IS_ENABLED(CONFIG_X86_32)) goto the_end; + if (state->task != current) + goto the_end; + if (state->regs) { printk_deferred_once(KERN_WARNING "WARNING: kernel stack regs at %p in %s:%d has bad 'bp' value %p\n", |