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| author | Xiyu Yang <xiyuyang19@fudan.edu.cn> | 2021-07-17 18:17:22 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-21 13:50:54 +0200 |
| commit | 03acb0c5ac46b1aa5f3015f1e01243aff9e08600 (patch) | |
| tree | 51b622e23f85de72a0f97ce3f4947a6b249fb0a5 /drivers/misc | |
| parent | 07e913418ce4ba5eb620dd4668bf91ec94e11136 (diff) | |
| download | linux-03acb0c5ac46b1aa5f3015f1e01243aff9e08600.tar.bz2 | |
misc: sgi-gru: Convert from atomic_t to refcount_t on gru_thread_state->ts_refcnt
refcount_t type and corresponding API can protect refcounters from
accidental underflow and overflow and further use-after-free situations.
Acked-by: Dimitri Sivanich <sivanich@hpe.com>
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Link: https://lore.kernel.org/r/1626517043-42696-1-git-send-email-xiyuyang19@fudan.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/misc')
| -rw-r--r-- | drivers/misc/sgi-gru/grumain.c | 6 | ||||
| -rw-r--r-- | drivers/misc/sgi-gru/grutables.h | 3 |
2 files changed, 5 insertions, 4 deletions
diff --git a/drivers/misc/sgi-gru/grumain.c b/drivers/misc/sgi-gru/grumain.c index 40ac59dd018c..9afda47efbf2 100644 --- a/drivers/misc/sgi-gru/grumain.c +++ b/drivers/misc/sgi-gru/grumain.c @@ -282,7 +282,7 @@ static void gru_unload_mm_tracker(struct gru_state *gru, */ void gts_drop(struct gru_thread_state *gts) { - if (gts && atomic_dec_return(>s->ts_refcnt) == 0) { + if (gts && refcount_dec_and_test(>s->ts_refcnt)) { if (gts->ts_gms) gru_drop_mmu_notifier(gts->ts_gms); kfree(gts); @@ -323,7 +323,7 @@ struct gru_thread_state *gru_alloc_gts(struct vm_area_struct *vma, STAT(gts_alloc); memset(gts, 0, sizeof(struct gru_thread_state)); /* zero out header */ - atomic_set(>s->ts_refcnt, 1); + refcount_set(>s->ts_refcnt, 1); mutex_init(>s->ts_ctxlock); gts->ts_cbr_au_count = cbr_au_count; gts->ts_dsr_au_count = dsr_au_count; @@ -888,7 +888,7 @@ again: gts->ts_gru = gru; gts->ts_blade = gru->gs_blade_id; gts->ts_ctxnum = gru_assign_context_number(gru); - atomic_inc(>s->ts_refcnt); + refcount_inc(>s->ts_refcnt); gru->gs_gts[gts->ts_ctxnum] = gts; spin_unlock(&gru->gs_lock); diff --git a/drivers/misc/sgi-gru/grutables.h b/drivers/misc/sgi-gru/grutables.h index 5ce8f3081e96..e4c067c61251 100644 --- a/drivers/misc/sgi-gru/grutables.h +++ b/drivers/misc/sgi-gru/grutables.h @@ -129,6 +129,7 @@ * */ +#include <linux/refcount.h> #include <linux/rmap.h> #include <linux/interrupt.h> #include <linux/mutex.h> @@ -358,7 +359,7 @@ struct gru_thread_state { enabled */ int ts_ctxnum; /* context number where the context is loaded */ - atomic_t ts_refcnt; /* reference count GTS */ + refcount_t ts_refcnt; /* reference count GTS */ unsigned char ts_dsr_au_count;/* Number of DSR resources required for contest */ unsigned char ts_cbr_au_count;/* Number of CBR resources |