🐛 fix bus error on smaller readonly file in unix

JuliaLang · Nov 8, 2022 · 817a8ee · 817a8ee
1 parent 5a323a6
commit 817a8ee
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/stdlib/Mmap/src/Mmap.jl b/stdlib/Mmap/src/Mmap.jl
@@ -212,6 +212,7 @@ function mmap(io::IO,
     @static if Sys.isunix()
         prot, flags, iswrite = settings(file_desc, shared)
         iswrite && grow && grow!(io, offset, len)
+        !iswrite && mmaplen > filesize(io) && throw(ArgumentError("unable to mmap file size smaller than $mmaplen due to read-only permissions. Please check your dims"))
         # mmap the file
         ptr = ccall(:jl_mmap, Ptr{Cvoid}, (Ptr{Cvoid}, Csize_t, Cint, Cint, RawFD, Int64),
             C_NULL, mmaplen, prot, flags, file_desc, offset_page)