openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

tracing/stack-tracer: avoid races accessing file 

Impact: fix race

vma->vm_file reference is only stable while holding the mmap_sem,
so move usage of it to within the critical section.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Török Edwin 2008-11-23 13:08:10 +02:00 committed by Ingo Molnar
parent 8d26487fd4
commit e38da59269
1 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
kernel/trace/trace.c
View File

@ -1470,13 +1470,13 @@ static inline int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
file = vma->vm_file; file = vma->vm_file;
vmstart = vma->vm_start; vmstart = vma->vm_start;
} }
if (file) {
ret = trace_seq_path(s, &file->f_path);
if (ret)
ret = trace_seq_printf(s, "[+0x%lx]", ip - vmstart);
}
up_read(&mm->mmap_sem); up_read(&mm->mmap_sem);
} }
if (file) {
ret = trace_seq_path(s, &file->f_path);
if (ret)
ret = trace_seq_printf(s, "[+0x%lx]", ip - vmstart);
}
if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file)) if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
ret = trace_seq_printf(s, " <" IP_FMT ">", ip); ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
return ret; return ret;