lkml.org 
[lkml]   [2021]   [Dec]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] RDMA/irdma: Fix a potential memory allocation issue in 'irdma_prm_add_pble_mem()'
On Sun, Dec 05, 2021 at 09:17:24AM +0100, Christophe JAILLET wrote:
> 'pchunk->bitmapbuf' is a bitmap. Its size (in number of bits) is stored in
> 'pchunk->sizeofbitmap'.
>
> When it is allocated, the size (in bytes) is computed by:
> size_in_bits >> 3
>
> There are 2 issues (numbers bellow assume that longs are 64 bits):
> - there is no guarantee here that 'pchunk->bitmapmem.size' is modulo
> BITS_PER_LONG but bitmaps are stored as longs
> (sizeofbitmap=8 bits will only allocate 1 byte, instead of 8 (1 long))
>
> - the number of bytes is computed with a shift, not a round up, so we
> may allocate less memory than needed
> (sizeofbitmap=65 bits will only allocate 8 bytes (i.e. 1 long), when 2
> longs are needed = 16 bytes)
>
> Fix both issues by using 'bitmap_zalloc()' and remove the useless
> 'bitmapmem' from 'struct irdma_chunk'.
>
> While at it, remove some useless NULL test before calling
> kfree/bitmap_free.
>
> Fixes: 915cc7ac0f8e ("RDMA/irdma: Add miscellaneous utility definitions")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
> drivers/infiniband/hw/irdma/pble.c | 6 ++----
> drivers/infiniband/hw/irdma/pble.h | 1 -
> drivers/infiniband/hw/irdma/utils.c | 9 ++-------
> 3 files changed, 4 insertions(+), 12 deletions(-)

Applied to for-rc, thanks

Jason

\
 
 \ /
  Last update: 2021-12-07 18:52    [W:1.181 / U:0.028 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site