[PATCH 4.9 239/310] sparc64: ldc abort during vds iso boot
4.9-stable review patch. If anyone has any objections, please let me know. -- From: Jag Raman[ Upstream commit 6c95483b768c62f8ee933ae08a1bdbcb78b5410f ] Orabug: 20902628 When an ldc control-only packet is received during data exchange in read_nonraw(), a new rx head is calculated but the rx queue head is not actually advanced (rx_set_head() is not called) and a branch is taken to 'no_data' at which point two things can happen depending on the value of the newly calculated rx head and the current rx tail: - If the rx queue is determined to be not empty, then the wrong packet is picked up. - If the rx queue is determined to be empty, then a read error (EAGAIN) is eventually returned since it is falsely assumed that more data was expected. The fix is to update the rx head and return in case of a control only packet during data exchange. Signed-off-by: Jagannathan Raman Reviewed-by: Aaron Young Reviewed-by: Alexandre Chartre Reviewed-by: Bijan Mottahedeh Reviewed-by: Liam Merwick Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/sparc/kernel/ldc.c |7 ++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/arch/sparc/kernel/ldc.c +++ b/arch/sparc/kernel/ldc.c @@ -1733,9 +1733,14 @@ static int read_nonraw(struct ldc_channe lp->rcv_nxt = p->seqid; + /* +* If this is a control-only packet, there is nothing +* else to do but advance the rx queue since the packet +* was already processed above. +*/ if (!(p->type & LDC_DATA)) { new = rx_advance(lp, new); - goto no_data; + break; } if (p->stype & (LDC_ACK | LDC_NACK)) { err = data_ack_nack(lp, p);
[PATCH 4.9 239/310] sparc64: ldc abort during vds iso boot
4.9-stable review patch. If anyone has any objections, please let me know. -- From: Jag Raman [ Upstream commit 6c95483b768c62f8ee933ae08a1bdbcb78b5410f ] Orabug: 20902628 When an ldc control-only packet is received during data exchange in read_nonraw(), a new rx head is calculated but the rx queue head is not actually advanced (rx_set_head() is not called) and a branch is taken to 'no_data' at which point two things can happen depending on the value of the newly calculated rx head and the current rx tail: - If the rx queue is determined to be not empty, then the wrong packet is picked up. - If the rx queue is determined to be empty, then a read error (EAGAIN) is eventually returned since it is falsely assumed that more data was expected. The fix is to update the rx head and return in case of a control only packet during data exchange. Signed-off-by: Jagannathan Raman Reviewed-by: Aaron Young Reviewed-by: Alexandre Chartre Reviewed-by: Bijan Mottahedeh Reviewed-by: Liam Merwick Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/sparc/kernel/ldc.c |7 ++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/arch/sparc/kernel/ldc.c +++ b/arch/sparc/kernel/ldc.c @@ -1733,9 +1733,14 @@ static int read_nonraw(struct ldc_channe lp->rcv_nxt = p->seqid; + /* +* If this is a control-only packet, there is nothing +* else to do but advance the rx queue since the packet +* was already processed above. +*/ if (!(p->type & LDC_DATA)) { new = rx_advance(lp, new); - goto no_data; + break; } if (p->stype & (LDC_ACK | LDC_NACK)) { err = data_ack_nack(lp, p);