Opened 7 years ago

Closed 7 years ago

Last modified 7 years ago

#11057 closed Patch (rejected)

String conversion functions failure

Reported by: Paolo Zambotti Owned by:
Priority: normal Component: libfilezilla
Keywords: string conversion wcsrtombs mbsrtowcs Cc:
Component version: trunk Operating system type: Windows
Operating system version: 10

Description

Some compilers (eg. mingw) library functions (surely wcsrtombs and, I guess, mbsrtowcs too) fail if the destination buffer size is 0, even if the destination pointer is NULL. In this case (NULL pointer) the function(s) returns the minimum between the real
string length and the destination buffer size. So, if the destination size is 0, the return value is always 0.
The attached patch turns the size parameter to -1 (this is a trick to set all the bits to 1 regardless of the parameter type) where the pointer is NULL.
I see this issue only when behind proxy with ASCII character support only.

Attachments (1)

string_conversions.patch (745 bytes ) - added by Paolo Zambotti 7 years ago.
patch file

Download all attachments as: .zip

Change History (3)

comment:1 by Paolo Zambotti, 7 years ago

Component: FileZilla Clientlibfilezilla

changed wrong component assignment

by Paolo Zambotti, 7 years ago

Attachment: string_conversions.patch added

patch file

comment:2 by Tim Kosse, 7 years ago

Resolution: rejected
Status: newclosed

Wrong place to fix. This is a bug in the C runtime in which it is not compliant to the C specifications. As such it is an issue that must be fixed upstream.

In case of the MinGW-w64 CRT I've already taken care of this: https://sourceforge.net/p/mingw-w64/mailman/mingw-w64-public/thread/5689BA84.6040808%40filezilla-project.org/#msg34737707

If you are using the MinGW-w64 CRT you need to update your toolchain. If you are using a different runtime, contact your runtime vendor for assistance.

Note that the unit tests in libfilezilla specifically test for this kind of CRT bug.

Last edited 7 years ago by Tim Kosse (previous) (diff)
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