Hi Tamar > -----Original Message----- > From: Tamar Christina <tamar.christ...@arm.com> > Sent: 30 July 2020 09:28 > To: gcc-patches@gcc.gnu.org > Cc: nd <n...@arm.com>; Richard Earnshaw <richard.earns...@arm.com>; > Marcus Shawcroft <marcus.shawcr...@arm.com>; Kyrylo Tkachov > <kyrylo.tkac...@arm.com>; Richard Sandiford > <richard.sandif...@arm.com> > Subject: [PATCH] AArch64: Fix hwasan failure in readline. > > Hi All, > > My previous fix added an unchecked call to fgets in the new function readline. > fgets can fail when there's an error reading the file in which case it returns > NULL. It also returns NULL when the next character is EOF. > > The EOF case is already covered by the existing code but the error case isn't. > This fixes it by returning the empty string on error. > > Also I now use strnlen instead of strlen to make sure we never read outside > the > buffer. > > This was flagged by Matthew Malcomson during his hwasan work. > > Bootstrapped Regtested on aarch64-none-linux-gnu and no issues. > > Ok for master? And for backport with the other patches? (haven't done > backport yet.)
Code looks ok, but I'm wondering what kind of input triggered this. Now that we can exercise this code in the testsuite (thanks!) perhaps a new test is in order? Thanks, Kyrill > > Thanks, > Tamar > > gcc/ChangeLog: > > * config/aarch64/driver-aarch64.c (readline): Check return value > fgets. > > --
