CVE-2024-26692

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> smb: Fix regression in writes when non-standard maximum write size negotiated<br /> <br /> The conversion to netfs in the 6.3 kernel caused a regression when<br /> maximum write size is set by the server to an unexpected value which is<br /> not a multiple of 4096 (similarly if the user overrides the maximum<br /> write size by setting mount parm "wsize", but sets it to a value that<br /> is not a multiple of 4096). When negotiated write size is not a<br /> multiple of 4096 the netfs code can skip the end of the final<br /> page when doing large sequential writes, causing data corruption.<br /> <br /> This section of code is being rewritten/removed due to a large<br /> netfs change, but until that point (ie for the 6.3 kernel until now)<br /> we can not support non-standard maximum write sizes.<br /> <br /> Add a warning if a user specifies a wsize on mount that is not<br /> a multiple of 4096 (and round down), also add a change where we<br /> round down the maximum write size if the server negotiates a value<br /> that is not a multiple of 4096 (we also have to check to make sure that<br /> we do not round it down to zero).